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Chapter I: Introduction

1.1 Introduction:

The Researcher Propose that Earthquake, Volcano and Tsunami,

these are the ultimate destroyer of the Natural Environment and Human

Environment. We usually think of the ground and the oceans are

peaceful things. The ground lies quietly beneath our feet, and the ocean

laps gently against the shore. But forces deep within the Earth can

suddenly destroy that peacefulness. These forces cause violent shakings

called earthquakes; explosions of ash, gases, and hot rocks called

volcanoes; and huge waves called tsunamis.

(i) Earthquake: The Researcher Propose that the plates usually

move very slowly. But sometimes large pieces of the plates get

caught. The plates keep trying to move, but these large blocks of

rock hold them back. The pressure and energy build up. Then,

suddenly, the rocks give way, releasing all that pressure and

energy. The plates jerk forward, and the ground shakes. Far

above, on the surface, people feel an earthquake. In a small

earthquake, the ground shakes a little, causing some hanging

objects to swing. Tree branches sway, as if there were a gentle

breeze. Some earthquakes are so small that we do not notice

them. But sometimes the shaking is so strong that buildings

crumble, bridges collapse, and large cracks open in the ground

over large areas.

(ii) Volcano: The Researcher Propose that a volcano occurs

wherever magma from deep inside the Earth comes out through a

crack in the surface. Volcanoes usually happen near the edges of

the plates, where there are many cracks and thin spots where the

magma can leak out. When the magma pours onto the surface, it

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hardens, often piling up into a mountain. Sometimes, the liquid

rock flows peacefully out across the land. This is how many of

the active volcanoes on the Hawaiian Islands behave.

(iii) Tsunami: The Researcher Propose that Tsunamis are huge waves

caused by earthquakes or volcanoes. They used to be called ―tidal

waves.‖ But the word ―tidal‖ means something to do with the

ocean‘s normal tides, and tsunamis have nothing to do with the

tides. Tsunamis can be as high as a football field is long. They

are the largest waves in the world.

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1.2 Introduction to Earthquake:

The Researcher Propose that earthquakes are nothing but natural

energy release driven by the evolutionary processes of the planet we live

on. Earthquakes have caused massive destruction to human life and

property, where these events have occurred near human settlements.

Earthquakes, therefore, are and were thought of as one of the worst

enemies of mankind.

Due to the very nature of release of energy, damage is evident

which, however, will not culminate in a disaster unless it strikes a

populated area. The twentieth century has seen anunparalled explosion in

the world‘s population and an exponential growth in the size and number

of villages, towns and cities across the globe. Various migrations have

led to abnormal densification of urban areas, surrounded by mushroom

growth of squatter settlements especially in the developing third world.

As cities increase in size, so the potential for massive destruction

increases. The risk of earthquake disaster, therefore, is fast increasing,

and is higher than at any time in our history.

It is primarily the loss of life and the human suffering after the

occurrence that is most important, therefore, all those factors which

contribute towards this are of vital importance. The main contributor and

the principle cause of deaths in most large-scale disasters is the total or

partial collapse of buildings. In earthquakes affecting a higher quality

building stock,

Earthquake is one of the most destructive natural hazards. They may

occur at any time of the year, day or night, with sudden impact and little

warning. They can destroy buildings and infrastructure in seconds,

killing or injuring the inhabitants. Earthquakes not only destroy the

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entire habitation but may de-stabilize the government, economy and

social structure of the country.

e.g., Japan and USA, more fatalities are caused by the failure of

non-structural elements or by the earthquake induced accidents e.g. fire,

overturning or collapse of free-standing walls etc. About 75% of

fatalities, however, are caused by the collapse of buildings, which

primarily are weak masonry buildings (adobe, rubble stone, or rammed

earth) or unreinforced fired brick and concrete block masonry that can

collapse even at low intensity of ground shaking. Unfortunately a very

large proportion of the world‘s current building stock of such buildings

resides in the developing third world or marginally developed world. On

the other hand the increasing population in the developing countries will

continue to be housed in these types of structures for a foreseeable

future.

Earthquakes are the manifestations of sudden release of strain

energy accumulated in the rocks over extensive periods of time in the

upper part of the Earth.

Sudden shaking of the ground caused by a disturbance deeper within

the crust of the Earth. Most earthquakes occur when masses of rock

straining against one another along fault lines suddenly fracture and slip.

The Earth's major earthquakes occur mainly in belts coinciding with the

margins of tectonic plates. These include the Circum-Pacific Belt, which

affects New Zealand, New Guinea, Japan, the Aleutian Islands, Alaska,

and the western coasts of North and South America; the Alpide Belt,

which passes through the Mediterranean region eastward through Asia;

oceanic ridges in the Arctic, Atlantic, and western Indian oceans; and the

rift valleys of East Africa. The ―size,‖ or magnitude, of earthquakes is

usually expressed in terms of the Richter scale, which assigns levels

from 1.0 or lower to 8.0 or higher. The largest quake ever recorded

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(Richter magnitude 9.5) occurred off the coast of Chile in 1960. The

―strength‖ of an earthquake is rated in intensity scales such as the

Mercalli scale, which assigns qualitative measures of damage to terrain

and structures that range from ―not felt‖ to ―damage nearly total.‖ The

most destructive quake of modern times occurred in 1976, when the city

of Tangshan, China, was leveled and more than 250,000 people killed.

Earthquakes ever recorded struck near Anchorage, Alaska,

measuring 8.4 to 8.6 in magnitude. Besides elevating some 70,000 sq mi

(181,300 sq km) of land and devastating several cities, it generated a

tsunami that caused damage as far south as California. Other recent

earthquakes that trembling or shaking movement of the earth's surface.

Most earthquakes are minor tremors. Larger earthquakes usually begin

with slight tremors but rapidly take the form of one or more violent

shocks, and end in vibrations of gradually diminishing force called

aftershocks. The subterranean point of origin of an earthquake is called

its focus; the point on the surface directly above the focus is the

epicenter. The magnitude and intensity of an earthquake is determined

by the use of scales, e.g., the moment magnitude scale, Richter scale ,

and the modified Mercalli scale. Causes of Earthquakes Most

earthquakes are causally related to compressional or tensional stresses

built up at the margins of the huge moving lithospheric plates that make

up the earth's surface (see lithosphere). The immediate cause of most

shallow earthquakes is the sudden release of stress along a fault, or

fracture in the earth's crust, resulting in movement of the opposing

blocks of rock past one another. These movements cause vibrations to

pass through and around the earth in wave form, just as ripples are

generated when a pebble is dropped into water. Volcanic eruptions, rock

falls, landslides, and explosions can also cause a quake, but most of these

are of only local extent. Shock waves from a powerful earthquake can

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trigger smaller earthquakes in a distant location hundreds of miles away

if the geologic conditions are favorable.

See also plate tectonics Seismic Waves There are several types of

earthquake waves including P, or primary, waves, which are

compressional and travel fastest; and S, or secondary, waves, which are

transverse, i.e., they cause the earth to vibrate perpendicularly to the

direction of their motion. Surface waves consist of several major types

and are called L, or long, waves. Since the velocities of the P and S

waves are affected by changes in the density and rigidity of the material

through which they pass, the boundaries between the regions of the earth

known as the crust, mantle, and core have been discerned by

seismologists; scientists who deal with the analysis and interpretation of

earthquake waves. Seismographs are used to record P, S, and L waves.

The disappearance of S waves below depths of 1,800 mi (2,900 km)

indicate that at least the outer part of the earth‘s core is liquid.

Seismology is the science of Earthquakes and related phenomena. 1

Seismograph:

The Researcher Propose that Seismograph is an instrument that records

the ground motions. Seismogram is a continuous written record of an

earthquake recorded by a seismograph.

1 Seismology word derived from Greek word Seismos meaning Earthquake and Logos meaning

science.

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Seismic Zonation Map of India:

The Researcher Propose that Seismic Zonation map of a country is a

guide to the seismic status of a region and its susceptibility to

earthquakes. India has been divided into five zones with respect to

severity of earthquakes. Of these, Zone V is seismically the most active

where earthquakes of magnitude 8 or more could occur recent strong

motion observations around the world have revolutionized thinking on

the design of engineering structures, placing emphasis also on the

characteristics of the structures themselves it should be realized that in

the case of shield type earthquakes, historic data are insufficient to define

zones because recurrence intervals are much longer than the recorded

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human history this may often give a false sense of security. Occurrence

of the damaging earthquake at Latur, falling in zone I is a typical

example of this situation.

The earth‘s crust is a rocky layer of varying thickness ranging from

a depth of about 10kilometers under the sea to 65 kilometers under the

continents. The crust is not one piece but consists of portions

called ‗plates‘ which vary in size from a few hundred to thousands of

kilometers. The ‗theory of plate tectonics‘ holds that the plates ride up on

the more mobile mantle, and are driven by some yet unconfirmed

mechanisms, perhaps thermal convection currents. When these plates

contact each other, stress arises in the crust. These stresses can be

classified according to the type of movement along the plate‘s

boundaries:

(a) Pulling away from each other,

(b) Pushing against one another and

(c) Sliding sideways relative to each other.

All these movements are associated with earthquakes. The areas of

stress at plate boundaries which release accumulated energy by slipping

or rupturing are known as 'faults'. The theory of 'elasticity' says that the

crust is continuously stressed by the movement of the tectonic plates; it

eventually reaches a point of maximum supportable strain. A rupture

then occurs along the fault and the rock rebounds under its own elastic

stresses until the strain is relieved. The fault rupture generates vibration

called seismic (from the Greek 'seismos' meaning shock or earthquake)

waves, which radiates from the focus in all directions. The point of

rupture is called the 'focus' and may be located near the surface or deep

below it. The point on the surface directly above the focus is termed as

the epicenter of the earthquake.

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Magnitude:

The Researcher Propose that it is a quantity to measure the size of an

earthquake and is independent of the place of the observation.

Richter scale:

The Researcher Propose that the local magnitude is defined as the

logarithm of the maximum amplitude measured in microns on a

seismogram written by Wood-Anderson seismograph with free period of

0.8 second, magnification of 2,800, damping factor of 0.8 calculated to

be at a distance of 100 kms. The relative size of events is calculated by

comparison to a reference event of ML=0, using the formula, ML=log A-

log Ao where A is the maximum trace amplitude in micrometer recorded

on a standard seismograph and Ao is a standard value which is a function

of epicentral distance (Δ) in kilometers.

Classification of earthquakes1

Category Magnitude on Richter Scale

Slight Up to 4.9

Moderate 5.0 to 6.9

Great 7.0 to 7.9

Very Great 8.0 and more

India has witnessed some of the most devastating earthquakes

during the last century like the one in Kangra (1905), Bihar-Nepal (1934)

and in Assam (1950). In the recent past, earthquakes have caused havoc

in Uttarkashi (1991), Latur (1993), Jabalpur (1997), Chamoli (1999) and

in Bhuj (2001). On 26th January 2001, India experienced one of the

worst earthquakes in recent times. Measuring 6.9 on the Richter scale,

the earthquake caused incalculable damage not just to its epicenter, Bhuj

but also to other towns of the district of Kutch and to about 500 villages

out of the total of 900 villages. The reported damage to property in

1 Source: www.imd.gov.in

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Gujarat was about Rs.21, 000crore and the numbers of human lives lost

were about 14,000. Of these, more than 500 deaths were reported from

Ahmedabad, situated at a distance of about 350 kms from Bhuj. In the

same city, close to 150 multi-storied buildings crumbled down. Cities far

away from the epicenter, like Surat, too reported damage to property.

Some damaging earthquake in India and appropriate number of

lives lost1

Year of

occurrence Place of

occurrence Intensity

Others

1618 Bombay - - 2000 lives lost

1720 Delhi 6.5 - Some lives lost

1737 Bengal - - 300,000 lives lost

1803 Mathura 6.5 - The shock felt up to

Calcutta.

1803 Kumaon 6.5 - Killed 200-300 people.

1819 Kutchch 8.0 XI

Chief towns of Tera,

Kathara and Mothala

razed to the ground.

1828 Srinagar 6.0 - 1000 people killed.

1833 Bihar 7.7 X Hundreds of people

killed

1848 Mt.Abu,

Rajasthan 6.0 - Few people killed

1869 Assam 7.5 - Affected an area of

2,50,000 Sq. miles.

1885 Srinagar 7.0 - Kamiarary area

destroyed.

1897 Shillong 8.7 XII

Wide spread

destruction in Shillong.

1905 Himachal

Pradesh 8.0 XI

Thousands of people

killed.

1906 Himachal

Pradesh 7.0 - Heavy damage.

1916 Nepal 7.5 - All houses collapsed at

Dharchulla.

1918 Assam 7.6 - Heavy damage.

1 Source: www.imd.gov.in

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1930 Dhubri,

Meghalaya 7.1 IX

Heavy damage in

Dhubri.

1934 Bihar, Nepal 8.3 XI Large number of border

area people killed.

1935 Quetta (in

Pakistan) 7.5 IX 25,000 people killed

1941 Andaman 8.1 X Very heavy damage.

1947 Dibrugarh 7.8 - Heavy damage.

1950 Assam 8.6 XII Heavy damage to life

and property.

1952 NE India 7.5 - Heavy damage.

1956 Bulandshahar,

U.P. 6.7 VIII Many people killed

1956 Anjar, Gujarat 7.0 VIII Hundreds of people

killed

1958 Kapkote, U.P. 6.3 VIII Many people killed

1967 Koyna, 6.1 VIII Koyna Nagar razed.

1969 Bhadrachalam 6.5 1 Heavy damage.

1986 Dharamshala

(H.P) 5.7 VIII Lots of damage.

1988 Assam 7.2 IX Few people killed

1988 Bihar- Nepal 6.5 VIII Large number of people

killed.

1991 Uttarkashi 6.6 VIII Lots of damage to life

and property.

1993 Latur 6.4 VIII

Heavy damage to life

and property about, 000

people killed.

1997 Jabalpur 6.0 VIII

Lots of damage to

property, about 39 lives

lost.

1999 Chamoli 6.8 VIII

Lots of damage to

property about 100

people lost lives.

2001 Bhuj 6.9 X

Huge devastation, about

~ 14000 people lost

lives

India has had a long history of earthquake occurrences. About 65% of

the total area of the country is vulnerable to seismic damage of buildings in

varying degrees. The most vulnerable areas, according to the present seismic

zone map of India, are located in the Himalayan and sub-Himalayan regions,

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Kutch and the Andaman and Nicobar Islands. Depending on varying degrees

of seism city, the entire country can be divided into the following seismic

regions:

Kashmir and Western Himalayas - Covers the states of Jammu and Kashmir,

Himachal Pradesh and sub-mountainous areas of Punjab

Central Himalayas - Includes the mountain and sub-mountain regions of

Uttar Pradesh and the sub-mountainous parts of Punjab

North-east India - Comprises the whole of Indian territory to the east of north

Bengal

Indo-Gangetic basin and Rajasthan - This region comprises of Rajasthan,

plains of Punjab, Haryana, Uttar Pradesh and West Bengal

Cambay and Rann of Kutch

Peninsular India, including the islands of Lakshwadeep

The Andaman and Nicobar Islands

Frequency of Occurrence of Earthquakes1

Descriptor Magnitude Average Annually

Great 8 and higher 1

Major 7 - 7.9 17

Strong 6 - 6.9 134

Moderate 5 - 5.9 1319

Light 4 - 4.9 13,000 (estimated)

Minor 3 - 3.9 130,000 (estimated)

Very Minor 2 - 2.9 1,300,000 (estimated)

Based on observations since 1900.

Based on observations since 1990.

1 Source: www.imd.gov.in

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Year-wise description of Earth Quakes

Number of Earthquakes Worldwide for 2000 - 2005. Located by the US

Geological Survey National Earthquake Information Center

Magnitude 2000 2001 2002 2003 2004 2005

8.0 to 9.9 1 1 0 1 2 1

7.0 to 7.9 14 15 13 14 14 9

6.0 to 6.9 158 126 130 140 140 116

5.0 to 5.9 1345 1243 1218 1203 1509 1307

4.0 to 4.9 8045 8084 8584 8462 10894 10264

3.0 to 3.9 4784 6151 7005 7624 7937 5782

2.0 to 2.9 3758 4162 6419 7727 6317 3249

1.0 to 1.9 1026 944 1137 2506 1344 20

0.1 to 0.9 5 1 10 134 103 0

No Magnitude 3120 2938 2937 3608 2939 642

Total 22256 23534 27454 31419 * 31199 * 21390

Estimated

Deaths

231 21357 1685 33819 284010 1957

List of Some Significant Earthquakes in India1

Date Epicenter Location Magnitude

1819 Jun 16 23.6 68.6 Kutch,Gujarat 8.0

1869 Jan 10 25 93 Near Cachar, Assam 7.5

1885 May 30 34.1 74.6 Sopor, J&K 7.0

1897 Jun 12 26 91 Shillongplateau 8.7

1905 Apr 04 32.3 76.3 Kangra, H.P 8.0

1918 Jul 08 24.5 91.0 Srimangal, Assam 7.6

1930 Jul 02 25.8 90.2 Dhubri, Assam 7.1

1934 Jan 15 26.6 86.8 Bihar-Nepalborder 8.3

1941 Jun 26 12.4 92.5 Andaman Islands 8.1

1943 Oct 23 26.8 94.0 Assam 7.2

1950 Aug 15 28.5 96.7 Arunachal Pradesh-China

Border 8.5

1956 Jul 21 23.3 7.0 Anjar, Gujarat 7.0

1967 Dec 10 17.37 73.75 Koyna, Maharashtra 6.5

1975 Jan 19 32.38 78.49 Kinnaur, Hp 6.2

1 Source: www.imd.gov.in

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1988 Aug 06 25.13 95.15 Manipur-Myanmar Border 6.6

1988 Aug 21 26.72 86.63 Bihar-Nepal Border 6.4

1991 Oct 20 30.75 78.86 Uttarkashi, Up Hills 6.6

1993 Sep 30 18.07 76.62 Latur - Osmanabad,

Maharashtra 6.3

1997 May 22 23.08 80.06 Jabalpur, MP 6.0

1999 Mar 29 30.41 79.42 Champoli, UP 6.8

2001 Jan 26 23.40 70.28 Bhuj, Gujarat 6.9

Some of the largest earthquakes of the world have occurred in India and

the earthquake engineering developments in the country started rather early.

After the 1897 Assam earthquake a new earthquake resistant type of housing

was developed which is still prevalent in the north-east India. The Baluchistan

earthquakes of 1930‘s led to innovative earthquake resistant constructions and to

the development of first seismic zone map. The institutional development started

in the late 1950‘s and earthquake engineering concepts have been applied to

numerous major projects in high seismic regions in the country. Extensive

damage during several moderate earthquakes in recent years indicate that despite

such early gains, earthquake risk in the country has been increasing alarmingly.

Most buildings even in high seismic regions of the country continue to be built

without appropriate earthquake resistant features. At the higher end of

earthquake technology, the gap between state-of-the practice of earthquake

engineering and research in India, bench-marked against the advanced countries,

has been widening.

The Researcher Propose that Indian earthquake problem cannot be

overemphasized. More than about 60% of the land area is considered prone to

shaking of intensity VII and above (MMI scale). In fact, the entire Himalayan

belt is considered prone to great earthquakes of magnitude exceeding 8.0, and in

a short span of about 50 years, four such earthquakes have occurred: 1897

Assam (M8.7), 1905 Kangra (M8.6), 1934 Bihar-Nepal (M8.4), and 1950

Assam-Tibet (M8.7). Earthquake engineering developments started rather early

in India. For instance, development of the first seismic zone map and of the

earthquake resistant features for masonry buildings took place in 1930‘s, and

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formal teaching and research in earthquake engineering started in late 1950‘s.

Despite an early start, the seismic risk in the country has been increasing rapidly

in the recent years. Five moderate earthquakes in the last eleven years (1988

Bihar-Nepal: M6.6, about 1,004 dead; 1991 Uttarkashi: M6.6, about 768 dead;

1993 Latur: M6.4, about 8,000 dead; 1997 Jabalpur: M6.0, about 38 dead; and

1999 Chamoli: M6.5, about 100 dead) have clearly underlined the inadequate

preparedness of the country to face damaging earthquakes. The paper discusses

the developments of earthquake engineering in India during the last one hundred

years, the current status of earthquake risk reduction in India, strengths and

weaknesses of Indian model of earthquake engineering developments, and the

future challenges.

Extensive Definition:

The Researcher Propose that an earthquake is the result of a sudden

release of energy in the Earth’s crust that creates seismic waves. Earthquakes are

recorded with a seismometer, also known as a seismograph. The moment

magnitude of an earthquake is conventionally reported, or the related and mostly

obsolete Richter magnitude, with magnitude 3 or lower earthquakes being

mostly imperceptible and magnitude 7 causing serious damage over large areas.

Intensity of shaking is measured on the modified Mercalli scale.

At the Earth's surface, earthquakes manifest themselves by a shaking and

sometimes displacement of the ground. When a large earthquake epicenter is

located offshore, the seabed sometimes suffers sufficient displacement to cause

a tsunami. The shaking in earthquakes can also trigger landslides and

occasionally volcanic activity.

In its most generic sense, the word earthquake is used to describe any

seismic event—whether a natural phenomenon or an event caused by humans—

that generates seismic waves. Earthquakes are caused mostly by rupture of

geological faults, huge amounts of gas migration, mainly methane deep within

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the earth, but also by volcanic activity, landslides, mine blasts, and nuclear

experiments.

An earthquake's point of initial rupture is called its focus or hypocenter.

The term epicenter means the point at ground level directly above this.

Naturally occurring earthquakes:

The Researcher Propose that tectonic earthquakes will occur anywhere

within the earth where there is sufficient stored elastic strain energy to drive

fracture propagation along a fault plane. In the case

of transform or convergent type plate boundaries, which form the largest fault

surfaces on earth, they will move past each other smoothly and a

seismically only if there are no irregularities or asperities along the boundary

that increase the frictional resistance. Most boundaries do have such asperities

and this leads to a form of stick-slip behavior. Once the boundary has locked,

continued relative motion between the plates leads to increasing stress and

therefore, stored strain energy in the volume around the fault surface. This

continues until the stress has risen sufficiently to break through the asperity,

suddenly allowing sliding over the locked portion of the fault, releasing the

stored energy. This energy is released as a combination of radiated

elastic strain seismic waves, frictional heating of the fault surface, and cracking

of the rock, thus causing an earthquake. This process of gradual build-up of

strain and stress punctuated by occasional sudden earthquake failure is referred

to as the Elastic-rebound theory. It is estimated that only 10 percent or less of an

earthquake's total energy is radiated as seismic energy. Most of the earthquake's

energy is used to power the earthquake fracture growth or is converted into heat

generated by friction. Therefore, earthquakes lower the Earth's available elastic

potential energy and raise its temperature, though these changes are negligible

compared to the conductive and convective flow of heat out from the Earth's

deep interior.

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Earthquakes away from plate boundaries:

The Researcher Propose that where plate boundaries occur within

continental lithosphere, deformation is spread out a over a much larger area than

the plate boundary itself. In the case of the San Andreas fault continental

transform, many earthquakes occur away from the plate boundary and are

related to strains developed within the broader zone of deformation caused by

major irregularities in the fault trace (e.g. the ―Big bend‖ region).

The Northridge earthquake was associated with movement on a blind thrust

within such a zone. Another example is the strongly oblique convergent plate

boundary between the Arabian and Eurasian plates where it runs through the

northwestern part of the Zagros mountains. The deformation associated with this

plate boundary is partitioned into nearly pure thrust sense movement‘s

perpendicular to the boundary over a wide zone to the southwest and nearly pure

strike-slip motion along the Main Recent Fault close to the actual plate boundary

itself. This is demonstrated by earthquake focal mechanisms.

All tectonic plates have internal stress fields caused by their interactions

with neighboring plates and sedimentary loading or unloading (e.g.

deglaciation). These stresses may be sufficient to cause failure along existing

fault planes, giving rise to intra-plate earthquakes.

Deep focus earthquakes:

The Researcher Propose that the majority of tectonic earthquakes

originate at depths not exceeding tens of kilometers. In subduction zones, where

older and colder oceanic crust descends beneath another tectonic plate, Deep

focus earthquakes may occur at much greater depths (up to seven hundred

kilometers). These seismically active areas of subduction are known as Wadati-

Benioff zones. These are earthquakes that occur at a depth at which the sub

ducted lithosphere should no longer be brittle, due to the high temperature and

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pressure. A possible mechanism for the generation of deep focus earthquakes is

faulting caused by olivine undergoing a phase transition into a spinal structure.

Earthquakes and volcanic activity:

The Researcher Propose that earthquakes also often occur in volcanic

regions and are caused there, both by tectonic faults and by the movement

of magma in volcanoes. Such earthquakes can serve as an early warning of

volcanic eruptions.

Earthquake storms:

The Researcher Propose that sometimes a series of earthquakes occur in

a sort of earthquake storm, where the earthquakes strike a fault in clusters, each

triggered by the shaking or stress redistribution of the previous earthquakes.

Similar to aftershocks but on adjacent segments of fault, these storms occur over

the course of years, and with some of the later earthquakes as damaging as the

early ones. Such a pattern was observed in the sequence of about a dozen

earthquakes that struck the North Anatolian Fault in Turkey in the 20th century,

the half dozen large earthquakes in New Madrid in 1811-1812, and has been

inferred for older anomalous clusters of large earthquakes in the Middle East

and in the Mojave Desert.

Size and frequency of occurrence:

The Researcher Propose that minor earthquakes occur nearly constantly

around the world in places like California and Alaska in the U.S., as well as in

Chile, Peru, Indonesia, Iran, Pakistan the Azores in Portugal, Turkey, New

Zealand, Greece, Italy, and Japan, Larger earthquakes occur less frequently, the

relationship being exponential; for example, roughly ten times as many

earthquakes larger than magnitude 4 occur in a particular time period than

earthquakes larger than magnitude 5. In the (low seismicity) United Kingdom,

for example, it has been calculated that the average recurrences are:

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An earthquake of 3.7 - 4.6 every year

An earthquake of 4.7 - 5.5 every 10 years

An earthquake of 5.6 or larger every 100 years.

The number of seismic stations has increased from about 350 in 1931 to

many thousands today. As a result, many more earthquakes are reported than in

the past because of the vast improvement in instrumentation (not because the

number of earthquakes has increased). The USGS estimates that, since 1900,

there have been an average of 18 major earthquakes (magnitude 7.0-7.9) and one

great earthquake (magnitude 8.0 or greater) per year, and that this average has

been relatively stable. In fact, in recent years, the number of major earthquakes

per year has actually decreased, although this is likely a statistical fluctuation.

More detailed statistics on the size and frequency of earthquakes is available

from the USGS.

Most of the world's earthquakes (90%, and 81% of the largest) take place

in the 40,000-km-long, horseshoe-shaped zone called the circum-Pacific seismic

belt, also known as the Pacific Ring of Fire, which for the most part bounds

the Pacific Plate. Massive earthquakes tend to occur along other plate

boundaries, too, such as along the Himalayan Mountains.

With the rapid growth of mega-cities such as Mexico City, Tokyo or

Tehran, in areas of high seismic risk, some seismologists are warning that a

single quake may claim the lives of up to 3 million people.

Earthquakes take place at locations where there are mountains. If you

want to know the exact locations, take the relief globe from your drawing room

and run your finger along the mountain line. You now have the complete data on

where most earthquakes have been occurring in the world. Now, that is not the

end of it. Earthquakes can and have been occurring at other locations too,

particularly where there are not necessarily any major mountain ranges; the

1993 earthquake in Deccan plateau of Marathwada in central India is a recent

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example of this from our country. This means that in India, virtually over 60%

of the area is under the threat of moderate to strong earthquake shaking.

Understanding earthquakes is an on-going process. Two questions are

most frequently asked: (a) why do earthquakes occur? And (b) Can we predict

earthquakes? Let us address the first one. There is a large differential pressure

and temperature between the center of the Earth and its surface; the pressure

inside is about 4 million atmospheres and the temperature about 6000°C. So

most matter inside the Earth is in the hot molten form of lava. This gradient

coupled with the presence of magnetic field of the Earth, generates a circulation

of the Earth's mass - from the North Pole to the South Pole along the axis and

from South Pole to the North Pole along the surface. Of course, the rate of this

motion is very small, on an average of about 2 inches per year in active

earthquake areas. The journey of the Earth's mass from the South Pole to the

North Pole is what all of us participate in. Understandably, since the pace of

motion is not uniform across the entire Earth, some parts move faster than the

others do. Consequently, the Earth's surface can be visualized to consist of a

number of pieces, called tectonic plates, which move towards the North Pole.

Also, the motion of these plates is not a smooth one but happens in fits and

starts, thanks to the limited strength of the Earth's material to resist the strains

generated by these relative motions. So, every time a tectonic plate moves more

than its neighbor and slips over it, large amount of strain energy is suddenly

released and there is a tremor of the Earth, which we call as an earthquake. The

junctions of these plates are named as faults. Again, many of these faults lie

along the mountains that all of us observe.

Now, coming to the second question on predicting earthquakes, it is

virtually impossible to predict when and where the next earthquake will occur in

the world. Reports of having predicted earthquakes are very hotly debated even

today. Most prediction studies are based on a presumed structure of the Earth's

cross-section and on very simplified models of the movement of the earth's

crust. These developments are based on a limited data that too from the top few

21

kilometers of the Earth's crust. Therefore, prediction studies have effectively not

taken off.

Earthquakes don‘t kill people; it is the structures built by man that kill

people. With frequent reminders of moderate earthquakes staring into our eyes,

India is at the crossroads of earthquake preparedness. It has only two options to

choose from – prepare now or pay later. For a country with relatively fragile

economy and with a very dense demographic distribution, the second option will

be a very costly proposition. Even if it means an uphill task, time is ripe to take

the challenge with open arms.

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1.3 Introduction to Volcanic eruptions:

The Researcher Propose that volcano vents or fissures in the earth's crust

through which gases, molten rock, or lava, and solid fragments are discharged.

Their study is called volcanology. The term volcano is commonly applied both

to the vent and to the conical mountain (cone) built up around the vent by the

erupted rock materials. Volcanoes are described as active, dormant, or extinct.

The soil resulting from decomposition of volcanic materials is extremely fertile,

and the ash itself is a good polishing and cleansing agent.

We have probably heard in the news about volcanic eruptions, or you

might remember when Mount St. Helens erupted. Perhaps you've even seen an

active volcano. Although they are often a destructive force, volcanoes are

amazing facets of creation. They come in a variety of shapes, sizes, and eruption

types.

Volcanoes erupt when magma, red-hot liquid rock, seeps up through a

vent in the earth. More violent eruptions occur when pyroclastic material - a

mixture of magma, rocks, ash, and hot gases - is exploded upward by pressure

caused by underground gases and magma.

When magma flows above the surface of the earth, it is called lava.

Usually lava changes from bright red to duller red, gray, or black as air causes it

to cool and solidify.

Volcanic eruptions vary in size and display. There are six common types

of eruptions, with differing features. Plinian eruptions usually have thick lava

and high gas content. They can shoot pyroclastic material high into the air,

moving at hundreds of feet per second. These eruptions can last for hours or

even days. Hawaiian eruptions are not usually very explosive; instead, they

produce streams of slow-moving lava. An interesting feature of Hawaiian

eruptions are "fire fountains", huge fountains of magma being spewed into the

air. These fountains last anywhere from a few minutes to a few hours.

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Strombolian eruptions put on an impressive display but are not usually very

dangerous. During these eruptions, lava is shot fifty to a few hundred feet into

the air and is accompanied by booming noises. These eruptions do not produce

much lava flow. Vulcanian eruptions do not have much lava flow either, but

they tend to be larger than Strombolian ones. They produce a lot of ash and spit

out "bombs" of hard pyroclastic material. Hydrovolcanic eruptions occur when

water vapor hits hot magma and gases, and forms huge steam clouds that rise

from the volcano. Fissure eruptions occur when magma leaks up through a long

crack in the ground. They are associated with "curtains of fire" - magma being

spewed up to a small height all along a fissure.

There are also different shapes and sizes of volcanoes. Stratovolcanos

are usually very high, with pointy tops. They are formed by repeated explosions,

usually Plinian, and by slow-moving lava. Eruptions from these volcanoes are

usually very large but occur infrequently. Mount Vesuvius, which buried the

Roman city of Pompeii in 79 AD, is a stratovolcano. Shield-type volcanoes are

usually spread out over a large area and have gently sloping sides. They are

caused by minor explosions (usually Hawaiian) and erupt more frequently than

stratovolcanoes. Most of the major volcanoes in Hawaii are shield volcanoes.

Scoria Cones are the most common volcano type, usually caused by Strombolian

eruptions. They are shaped like upside-down cones, with slightly squished tops.

Scoria cones usually erupt only once.

Origin of Volcano:

The Researcher Propose that volcanoes are one of the most dynamic,

powerful, and visible forces on Earth. What are volcanoes and what factors

cause them to form in certain areas? How are geothermal features like fumaroles

and geysers related to these temperamental mountains?

Let us start by looking at the volcano itself and learn the different parts

of it, the rocks associated with it, and where volcanoes form.

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Form of Volcano:

The Researcher Propose that hot magma, melted rock below Earth's

crust, rises and collects in a magma chamber deep below the surface. If the

magma flows through a conduit up to a vent on the surface, then it may cause an

eruption and form a volcano.

Gases, lava, and pyroclastic material are erupted from volcanic vents.

The mountain that forms from layers of lava and tephra is called a volcano. The

word "volcano" comes from the name of a Roman god, Vulcan, who was the

god of fire. Magma that solidifies inside a volcano can form dikes and sills.

Volcanoes are classified as active, dormant or extinct.

The Magma Chamber:

The Researcher Propose that magma is the name given to melted liquid

rock below Earth's surface. It is stored below the volcano in a chamber or

reservoir. During active periods, this reservoir fills with magma. After a large

eruption, or during dormancy, this reservoir can drain, which may trigger the

creation of a caldera.

The Magma Conduit:

The Researcher Propose that the magma conduit is the plumbing system

of the volcano. Molten magma creates ―pipes‖, through the volcano. Magma

then travels through them to the surface.

The Main Vent:

The Researcher Propose that the main vent often is located at or near the

summit of the volcano. This is where most eruptive activity (lava flows,

pyroclastic flows, and large gas emissions) occurs.

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Lava Flows:

The Researcher Propose that Lava flows occur during some eruptions.

Once magma reaches the vent and flows onto the surface of Earth it is called

lava. Lava flows add land to the surface, and build the mountains we call

volcanoes. The island of Hawaii is nearly 100% cooled and solidified lava!

Pyroclastic Flows:

The Researcher Propose that pyroclastic flows occur during some

eruptions. These are super-heated clouds of volcanic material ranging from ash

to volcanic bombs. Pyroclastic flows travel very fast, and can destroy everything

in their path.

The Volcano:

The Researcher Propose that volcanoes are built from layers of lava and

tephra (particles of rock, solidified lava, and ash of all different sizes). The lava

cools on the sides of the volcano and hardens into rock. Pyroclastic flows and

eruption clouds deposit tephra on top of lava layers, increasing the size of the

mountain.

Dikes and Sills:

The Researcher Propose that the molten, pressurized magma intrudes

into the solid volcanic rock to create dikes and sills. Dikes cut across volcanic

rock layers, and sills run parallel to the layers. Eventually the magma hardens

inside Earth and becomes an intrusive igneous rock.

Vulcan, Roman God of Fire:

The Researcher Propose that in Roman mythology, Vulcan was the god

of fire. He was also known as the blacksmith of the gods.

There is a small volcanic island in the Mediterranean Sea called

Vulcano. The local residents once believed the volcano on the island was the

26

chimney of Vulcan's workshop. They thought the hot lava and smoke issuing

from the mountain were products of Vulcan's work as he created thunderbolts

for Jupiter, king of the gods, and weapons for Mars, god of war.

Active, Dormant, and Extinct:

The Researcher Propose that volcanologists classify volcanoes based on

how much activity has been recorded over time.

Active:

The Researcher Propose that an active volcano is currently erupting or

has erupted in recent history. Active volcanoes can have eruptions of gases,

pyroclastic material, tephra, and lava.

Dormant:

The Researcher Propose that a dormant volcano is not presently erupting,

and has not erupted in recent history. There is still potential for renewed activity,

because there still may be magma moving or cooling deep inside the volcano.

Extinct:

The Researcher Propose that an extinct volcano has not erupted in recent

history and is unlikely to erupt again. Wind and water have broken and

smoothed the shape of the mountain. The magma has drained below the surface

or cooled inside the volcano.

Magma:

The Researcher Propose that magma is the word used to describe melted

or molten rock inside Earth. Magma is composed of elements, minerals, and

gases that were present in the rock before it melted.

The major elements in magma are those present in Earth's crust: oxygen

(O), silicon (Si), aluminum (Al), iron (Fe), calcium (Ca), sodium (Na),

magnesium (Mg), and potassium (K). These elements combine to form minerals

27

such as magnetite, hauynite, olivine, pyroxene, hornblende, plagioclase,

potassium feldspar (k-feldspar), and quartz.

Magma also contains dissolved gases like water vapor (H2O), carbon

dioxide (CO2), and sulfur dioxide (SO2).

Composition on Magma:

The Researcher Propose that the composition of the magma determines

the eruption style, rock type, and volcano shape. Variations in the chemical

compositions and properties of the magma determine whether it will be

classified as mafic, felsic, or intermediate.

Types of Volcanoes:

The Researcher Propose that volcanoes are openings, or vents, in the

surface of Earth where gases, lava and pyroclastic material are erupted. Because

of the different types of magma, and the locations where they form, volcanoes

can have a wide variety of shapes and sizes.

Volcanoes are classified based on their height, shape, magma type, and

eruption style. In this section, you can learn about four types of volcanoes.

The two primary types are shield volcanoes and composite volcanoes.

Cinder cones and lava domes are considered to be secondary cones, because

they occur on or near composite or shield volcanoes.

Shield Volcanoes:

The Researcher Propose that Shield volcanoes have the shape of a

warrior's shield lying flat on the ground: very broad with large bases. This is due

to the low viscosity of the magma. They are not as steep as composite

volcanoes, but are often greater in volume.

Shield volcanoes usually have slow, gentle eruptions that produce large

volumes of mafic magma (rich in iron and magnesium). Although these

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eruptions are usually relatively quiet, there can be large explosions when magma

comes into contact with groundwater, vaporizing the water instantly. Shield

volcanoes are found commonly in oceanic areas, such as Hawaii. The Big Island

of Hawaii is made up of five huge shield volcanoes.

Formation of Shield Volcanoes:

The Researcher Propose that Explore the steps involved in the formation

and growth of a shield volcano.

Initial Vent Formation:

The Researcher Propose that a magma reservoir sits below the ocean

floor. Pressure builds, pushing the magma closer and closer to the surface. Small

vents and fissures open on the ocean floor, and lava escapes. Pillow lavas form

when the molten rock comes in contact with the cold seawater.

Shield Building:

The Researcher Propose that many successive lava flows, over thousands

or even millions of years build a mountain that is shaped like a warrior's shield.

Eruptions happen often, and large amounts of lava are poured out of the vent, so

the mountains can grow to immense proportions.

Lava Fountains:

The Researcher Propose that Shield volcano eruptions are commonly

gentle and effusive, with great quantities of basaltic lava flowing out of the vent.

Mafic magma has low viscosity and flows easily, so lava from a shield volcano

can flow great distances. Sometimes spectacular lava fountains occur when

molten rock is squirted thousands of feet in the air above an erupting vent.

Eruptions and Intrusions:

The Researcher Propose that magma rising from a sea-floor vent can

come to the surface to cause an eruption at the main vent or at a fissure or

29

smaller vent on the flank of the volcano. Magma can also create intrusive

igneous structures like dikes and sills.

Caldera Formation:

The Researcher Propose that after an eruption all of the magma has

either been expelled through the vents, or has drained back into a reservoir deep

below the volcano. The conduits through which it flowed are left hollow and

empty. Because of the heavy weight of hardened lava over the unstable, empty

magma conduits, the summit of the volcano can collapse, forming a huge crater

known as a caldera.

Erosion and Reef Building:

The Researcher Propose that erosion from the wind and waves carves

away at the volcano's summit and flanks. The volcano's height is reduced as it is

eroded from the top, and the weight of the layers and layers of lava causes the

volcano to subside (sink). Sandy sediments build up, and coral reefs begin to

grow in the shallow water. As water depth increases, the coral die from lack of

sunlight. New reefs can grow on top of the deeper ones.

Atoll Formation:

The Researcher Propose that continued erosion and subsidence (sinking)

of the volcano reduce its height to sea level or below. Coral reefs keep growing,

building on each other in the shallow water. The reefs eventually form an atoll,

which is a group of islands in the shape of a ring with a lagoon in the middle.

Seamount Formation:

The Researcher Propose that eventually the volcano sinks faster than the

reefs are growing. Below sea level wave erosion flattens the top of the volcano,

which is now called a seamount.

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Shield Volcanoes in National Parks

Explore some of America's national parks where shield volcanoes can be found.

Hawaii Volcanoes National Park

Wrangell-St. Elias National Park and Preserve

Composite Volcanoes:

The Researcher Propose that these volcanoes are also called

stratovolcanoes because they are made from many layers (strata) of rock, ash,

and hardened lava. In addition, volcanic mudflows (lahars) can make up some of

the layers.

Composite volcanoes experience very explosive eruptions because of the

intermediate to felsic magma types (high viscosity, high silica, low melting

temperature). Composite volcanoes are steeper near the summit, but slope more

gently near the base of the mountain. Composite volcanoes are typically found

on island arcs and continents at subduction zones.

How Composite Volcanoes Form

Explore the steps involved in the formation and growth of a composite

volcano.

Magma Reservoir:

The Researcher Propose that a magma reservoir sits below the ground in

Earth's crust. Composite volcanoes form in areas where subduction occurs.

Subduction happens when tectonic plates collide and one plate is pushed below

the other into the interior of Earth.

The magma creating composite volcanoes is likely to have a high content

of silica, making it explosive. As the volume of magma in the reservoir

increases, pressure builds until a vent opens in the ground and a volcano is

formed.

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Lava Layers:

The Researcher Propose that composite volcanoes are also called

tratovolcanoes because they are composed of layers (strata) of lava flows,

tephra, and mudflows. Lava, magma that has reached Earth's surface, pours out

of the main vent at the summit of the volcano, flows down its sides and hardens

to form a steep mountain.

Tephra Layers:

The Researcher Propose that composite volcano eruptions do not always

involve lava. Some eruptions release pressurized volcanic gases in great

explosions that expel tephra (ash, lapilli, cinders, bombs) into the air. This

material can fall back onto the volcano, adding another layer to its height and

width.

Continued Layering:

The Researcher Propose that an eruption of lava flows and pyroclastic

material continue, building a mountain that will be thousands of feet high.

Typically, composite volcanoes erupt andesite-based lava, but they can contain

lava of any composition from basalt to rhyolite.

Continued Layering:

The Researcher Propose that composite volcanoes are usually active over

hundreds of thousands of years. During this time, there are many eruptions with

periods of dormancy between them. Generally, lava flows and pyroclastic

deposits do not occur in the same eruption. The volcanoes grow to great heights,

typically having a gentle slope at the base, and a steeper slope at the summit.

Explosive Eruptions:

The Researcher Propose that composite volcanoes frequently erupt

explosively. Magma can push its way inside the volcano to form dikes and sills,

or flow out of a vent. Composite volcanoes can have multiple vents, at the

32

summit and on the flanks of the mountain. Lahars (volcanic mudflows) can

course down the side of the volcano, and hot pyroclastic flows rush down slope

carrying gases, tephra, and debris at high speeds and temperatures.

Caldera Formation:

The Researcher Propose that during an eruption, the magma and gases

that were creating high pressures inside the volcano are released. This leaves the

top of the mountain very unstable. This instability can cause the summit of the

volcano to collapse in on itself, forming a caldera.

Lava Dome Formation:

The Researcher Propose that renewed volcanism in the caldera can lead

to the formation of lava domes in the caldera. Lava domes form when viscous

lava pours out of the vent. Volcanic gas and steam are still released from the

caldera as the magma and pyroclastic material cool.

Erosion:

The Researcher Propose that after many thousands or millions of years,

the summit and flanks of the dormant volcano are eroded and smoothed. The

layers of the volcano that were formed from tephra and mudslides erode more

easily than the layers formed from lava flows. Erosion can also expose intrusive

igneous rocks like dikes and sills that formed inside the volcano's layers.

Composite Volcanoes in National Parks:

The Researcher Propose that explore some of America's national parks

where composite volcanoes can be found.

Aniakchak National Monument and Preserve

Katmai National Park and Preserve

Lake Clark National Park and Preserve

Mount Rainier National Park

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North Cascades National Park

Cinder Cones:

The Researcher Propose that Cinder cones are considered secondary

cones because they generally form in areas of other volcanic activity, including

on composite and shield volcanoes. Cinder cones are peaks formed when

pyroclastic materials are ejected into the air from a vent and fall back to the

ground around the vent in a cone-shaped pile resembling a mound of cinders.

The cones are small, steep-sided, and symmetrical. These volcanoes can

form individually over a vent. They can also form in the crater or on the flank of

another larger volcano. Wizard Island in Crater Lake National Park in Oregon

formed after the summit of Mount Mazama collapsed.

34

1.4 Introduction to Tsunami:

The Researcher Propose that the term tsunami comes from the Japanese

word, composed of the two tsu (tsu) meaning "harbour" and nami (nami),

meaning "wave". (For the plural, one can either follow ordinary English practice

and add an s, or use an invariable plural as in the Japanese.)

Tsunamis are sometimes referred to as tidal waves, which are unusually

high sea waves that are triggered especially by earthquakes. In recent years, this

term has fallen out of favor, especially in the scientific community, because

tsunamis actually have nothing to do with tides. The once-popular term derives

from their most common appearance, which is that of an extraordinarily high

tidal bore. Tsunami and tides both produce waves of water that move inland, but

in the case of tsunami the inland movement of water is much greater and lasts

for a longer period, giving the impression of an incredibly high tide. Although

the meanings of "tidal" include "resembling" or "having the form or character of

the tides, and the term tsunami is no more accurate because tsunami are not

limited to harbours, use of the term tidal wave is discouraged by geologists and

oceanographers.

As early as 426 BC the Greek historian Thucydides inquired in his book

History of the Peloponnesian War about the causes of tsunami, and was the first

to argue that ocean earthquakes must be the cause.

"The cause, in my opinion, of this phenomenon must be sought in the

earthquake. At the point where its shock has been the most violent the sea is

driven back, and suddenly recoiling with redoubled force, causes the inundation.

Without an earthquake I do not see how such an accident could happen."

The Roman historian Ammines Marcellinus described the typical

sequence of a tsunami, including an incipient earthquake, the sudden retreat of

the sea and a following gigantic wave, after the 365 AD tsunami devastated

Alexandria.

35

While Japan may have the longest recorded history of tsunamis, the

sheer destruction caused by the 2004 Indian Ocean earthquake and tsunami

event mark it as the most devastating of its kind in modern times, killing around

230,000 people. The Sumatran region is not unused to tsunamis either, with

earthquakes of varying magnitudes regularly occurring off the coast of the

island.

Tsunami can be generated when the sea floor rapidly deforms and

vertically displaces the overlying water. Tectonic earthquakes are a particular

kind of earthquake that are associated with the Earth's crustal deformation; when

these earthquakes occur beneath the sea, the water above the deformed area is

displaced from its equilibrium position. More specifically, a tsunami can be

generated when thrust faults associated with convergent or destructive plate

boundaries move abruptly, resulting in water displacement, owing to the vertical

component of movement involved. Movement on normal faults will also cause

displacement of the seabed, but the size of the largest of such events is normally

too small to give rise to a significant tsunami.

Tsunamis have a small amplitude (wave height) offshore, and a very

long wavelength (often hundreds of kilometers long, whereas normal ocean

waves have a wavelength of only 30 or 40 meters), which is why they generally

pass unnoticed at sea, forming only a slight swell usually about 300 millimeters

(12 in) above the normal sea surface. They grow in height when they reach

shallower water, in a wave shoaling process described below. A tsunami can

occur in any tidal state and even at low tide can still inundate coastal areas.

On April 1, 1946, a magnitude-7.8 (Richter scale) earthquake occurred

near the Aleutian Islands, Alaska. It generated a tsunami which inundated Hilo

on the island of Hawai'i with a 14-metre high (46 ft) surge. The area where the

earthquake occurred is where the Pacific Ocean floor is sub ducting (or being

pushed downwards) under Alaska.

36

Examples of tsunami originating at locations away from convergent

boundaries include Storegga about 8,000 years ago, Grand Banks 1929, Papua

New Guinea 1998 (Tappin, 2001). The Grand Banks and Papua New Guinea

tsunamis came from earthquakes which destabilized sediments, causing them to

flow into the ocean and generate a tsunami. They dissipated before traveling

transoceanic distances.

The cause of the Storegga sediment failure is unknown. Possibilities

include an overloading of the sediments, an earthquake or a release of gas

hydrates (methane etc.).

The 1960 Valdivia earthquake (Mw 9.5) (19:11 hrs UTC), 1964 Alaska

earthquake (Mw 9.2), 2004 Indian Ocean earthquake (Mw 9.2) (00:58:53 UTC)

and 2011 Tōhoku earthquake (Mw9.0) are recent examples of powerful mega

thrust earthquakes that generated tsunamis (known as teletsunamis) that can

cross entire oceans. Smaller (Mw 4.2) earthquakes in Japan can trigger tsunamis

(called local and regional tsunamis) that can only devastate nearby coasts, but

can do so in only a few minutes.

Origin of Tsunami:

•Tsunamis are generated by any large, impulsive displacement of the sea bed

level.

• Earthquakes generate tsunamis by vertical movement of the sea floor. If the sea

floor movement is horizontal, a tsunami is not generated. Earthquakes of M 6.5

are critical for tsunami generation.

• Tsunamis are also triggered by landslides into or under the water surface, and

can be generated by volcanic activity and meteorite impacts.

37

Occurrences of Tsunami:

• On the average, there are two tsunamis per year somewhere in the world which

cause damage near the source.

• Approximately every 15 years a destructive, Pacific-wide tsunami occurs.

• The destructive tsunami on Dec 26th, 2004 on the Indian Coast seems to have

occurred for the first time in the history.

Travel of Tsunami:

• Tsunami velocity is dependent on the depth of water through which it travels.

• Tsunamis travel approximately 700 kmph in 4000 m depth of sea water. In 10

m of water depth the velocity drops to about 36 kmph.

• For example, the tsunami from Sumatra coastal earthquake traveled to Tamil

Nadu coast in about two hours.

• Even on shore tsunamis can faster than a person can run.

Size of Tsunami:

• Tsunamis range in size from centimeters to over 30 m height. Most tsunamis

are less than 3 m in height.

• In deep water (greater than 200 m), tsunamis are rarely over 1m high and will

not be noticed by ships due to their long period (time between crests).

• As tsunamis propagate into shallow water, the wave height can increase by

over 10 times.

• Tsunami heights can vary greatly along a coast. The waves are amplified by

certain shoreline and bathymetric (sea floor) features.

• A large tsunami can flood land up to more than 1.5 km from the coast.

38

• The force of some tsunamis is enormous. Large rocks weighing several tons

along with boats and other debris can be moved inland hundreds of feet by

tsunami wave activity. Homes and other buildings are destroyed. All this

material and water move with great force and can kill or injure people.

Some Historical Tsunamis:

The Researcher Propose that prior to the Tsunami of 26 December 2004,

the most destructive Pacific-wide Tsunami of recent history was generated along

the coast of Chile on May 22, 1960. No accurate assessment of the damage and

deaths attributable to this Tsunami along the coast of Chile can be given;

however, all coastal towns between the 36th and 44th (latitude) parallels either

were destroyed or heavily damaged by the action of the waves and the quake.

The combined Tsunami and earthquake toll included 2,000 killed, 3000 injured

2,000,000 homeless and $550 million damages. Off Corral, the waves were

estimated to be 20.4 meters (67 feet) high. The Tsunami caused 61 deaths in

Hawaii, 20 in the Philippines, and 100 or more in Japan. Estimated damages

were $50 million in Japan, $24 million Hawaii and several millions along the

west coast of the United States and Canada. Wave heights varied from slight

oscillations in some areas to range of 12.2 meters (40 feet) at Pitcairn Islands;

10.7 meters (35 feet) at Hilo, Hawaii and 6.1 meters (20 feet) at various places

in Japan.

The hydrographic survey in Japan after the great Kwato earthquake of

September 1, 1923 showed that vertical displacements of the order of 100

meters had occurred over a large area of sea floor. Tsunamis are very common

over the Pacific Ocean because it is surrounded on all sides by a seismically

active belt. In the Hawain Islands, Tsunamis approach from all directions,

namely, from Japan, the Aleutian Islands and from South America.

39

Tsunami Risk in India:

The Researcher Propose that the Indian coastal belt has not recorded

many Tsunamis in the past. Waves accompanying earthquake activity have been

reported over the North Bay of Bengal. During an earthquake in 1881 which had

its epicenter near the centre of the Bay of Bengal, Tsunamis were reported. The

earthquake of 1941 in Bay of Bengal caused some damage in Andaman region.

This was unusual because most Tsunamis are generated by shocks which occur

at or near the flanks of continental slopes. During the earthquakes of 1819 and

1845 near the Rann of Kutch, there were rapid movements of water into the sea.

There is no mention of waves resulting from these earthquakes along the coast

adjacent to the Arabian Sea, and it is unlikely that Tsunamis were generated.

Further west, in the Persian Gulf, the 1945 Mekran earthquake (magnitude 8.1)

generated Tsunami of 12 to 15 meters height. This caused a huge deluge, with

considerable loss of life and property at Ormara and Pasi. The estimated height

of Tsunami at Gulf of Bombay was 15m but no report of damage is available.

The estimated height of waves was about 2 meters at Mumbai, where boats were

taken away from their moorings and casualties occurred. A list showing the

Tsunami that affected Indian coast in the past is given in Table-3.2. The

information given in the Table is sketchy and authenticity cannot be confirmed

except the Tsunami of 26th December 2004.

Above facts indicate the coastal region of Gujarat is vulnerable to

Tsunamis from great earthquakes in Mekran coast. Earthquake of magnitude 7

or more may be dangerous. It may be noted that all earthquake do not generate

Tsunami. Research is still being undertaken in this field. For the Indian region,

two potential sources have been identified, namely Mekran coast and Andaman

to Sumatra region.

Model generated Travel time of 26th December Tsunami is shown in Fig

3.1. Fig. 3.2 indicates the wave heights generated by the model which show the

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wave heights in Indian coast could have been between 2-4 meter. (Actual on

some coasts was observed more than 4m)

The 2004 Indian Ocean earthquake was an undersea mega thrust

earthquake that occurred at 00:58:53 UTC on Sunday, 26 December 2004, with

an epicenter off the west coast of Sumatra, Indonesia. The quake itself is known

by the scientific community as the Sumatra–Andaman earthquake. The resulting

tsunami was given various names, including the 2004 Indian Ocean tsunami,

South Asian tsunami, Indonesian tsunami, the Christmas tsunami and the

Boxing Day tsunami.

The earthquake was caused when the Indian Plate was sub ducted by the

Burma Plate and triggered a series of devastating tsunamis along the coasts of

most landmasses bordering the Indian Ocean, killing over 230,000 people in

fourteen countries, and inundating coastal communities with waves up to 30

meters (100 ft) high. It was one of the deadliest natural disasters in recorded

history. Indonesia was the hardest-hit country, followed by Sri Lanka, India, and

Thailand.

With a magnitude of Mw 9.1–9.3, it is the third largest earthquake ever

recorded on a seismograph. The earthquake had the longest duration of faulting

ever observed, between 8.3 and 10 minutes. It caused the entire planet to vibrate

as much as 1 centimeter (0.4 inches) and triggered other earthquakes as far away

as Alaska. Its epicenter was between Simeulue and mainland Indonesia. The

plight of the affected people and countries prompted a worldwide humanitarian

response. In all, the worldwide community donated more than $14 billion (2004

US$) in humanitarian aid.

Tsunami Risk in Asia:

The Researcher Propose that the earthquake was initially documented as

moment magnitude 8.8. In February 2005 scientists revised the estimate of the

magnitude to 9.0. Although the Pacific Tsunami Warning Center has accepted

41

these new numbers, the United States Geological Survey has so far not changed

its estimate of 9.1. The most recent studies in 2006 have obtained a magnitude

of Mw 9.1–9.3. Dr. Hiroo Kanamori of the California Institute of Technology

believes that Mw 9.2 is a good representative value for the size of this great

earthquake.

The hypocenter of the main earthquake was approximately 160 km (100

mi), in the Indian Ocean just north of Simeulueisland, off the western coast of

northern Sumatra, at a depth of 30 km (19 mi) below mean sea level (initially

reported as 10 km (6.2 mi)). The northern section of the Sunda mega thrust,

ruptured; the rupture having a length of 1,300 km (810 mi). The earthquake

(followed by the tsunami) was felt simultaneously in Bangladesh, India,

Malaysia, Myanmar, Thailand, Singapore and the Maldives. Splay faults, or

secondary "pop up faults", caused long, narrow parts of the sea floor to pop up

in seconds. This quickly elevated the height and increased the speed of waves,

causing the complete destruction of the nearby Indonesian town of Lhoknga.

Indonesia lies between the Pacific Ring of Fire along the north-eastern

islands adjacent to New Guinea, and the Alpide belt that runs along the south

and west from Sumatra, Java, Bali, and Flores to Timor.

Great earthquakes such as the Sumatra-Andaman event, which are

invariably associated with mega thrust events insubduction zones, have seismic

moments that can account for a significant fraction of the global earthquake

moment across century-scale time periods. Of all the seismic moment released

by earthquakes in the 100 years from 1906 through 2005, roughly one-eighth

was due to the Sumatra-Andaman event. This quake, together with the Good

Friday Earthquake (Alaska, 1964) and the Great Chilean Earthquake (1960),

account for almost half of the total moment. The much smaller but still

catastrophic 1906 San Francisco earthquake is included in the diagram below for

perspective. Mw denotes the magnitude of an earthquake on the moment

magnitude scale.

42

Since 1900 the only earthquakes recorded with a greater magnitude were

the 1960 Great Chilean Earthquake (magnitude 9.5) and the 1964 Good Friday

Earthquake in Prince William Sound (9.2). The only other recorded earthquakes

of magnitude 9.0 or greater were off Kamchatka, Russia, on 4 November 1952

(magnitude 9.0)[17] and Tōhoku, Japan (magnitude 9.0) in March 2011. Each of

these mega thrust earthquakes also spawned tsunamis in the Pacific Ocean.

However, the death toll from these was significantly lower, primarily because of

the lower population density along the coasts near affected areas and the much

greater distances to more populated coasts and also due to the superior

infrastructure and warning systems in MEDCs (More Economically Developed

Countries) such as Japan.

Other very large mega thrust earthquakes occurred in 1868 (Peru, Nazca

Plate and South American Plate); 1827 (Colombia, Nazca Plate and South

American Plate); 1812 (Venezuela, Caribbean Plate and South American Plate)

and1700 (western North America, Juan de Fuca Plate and North American

Plate). All of them are believed to be greater than magnitude 9, but no accurate

measurements were available at the time.

Tectonic plates:

The Researcher Propose that the mega thrust earthquake was unusually

large in geographical and geological extent. An estimated 1,600 kilometers

(1,000 mi) of fault surface slipped (or ruptured) about 15 meters (50 ft) along

the subduction zone where the Indian Plate slides (or sub ducts) under the

overriding Burma Plate. The slip did not happen instantaneously but took place

in two phases over a period of several minutes:

Seismographic and acoustic data indicate that the first phase involved a

rupture about 400 kilometers (250 mi) long and 100 kilometers (60 mi) wide,

located 30 kilometers (19 mi) beneath the sea bed—the largest rupture ever

known to have been caused by an earthquake. The rupture proceeded at a speed

43

of about 2.8 kilometers per second (1.7 miles per second) (10,000 km/h or 6,200

mph), beginning off the coast of Aceh and proceeding north-westerly over a

period of about 100 seconds.

A pause of about another 100 seconds took place before the rupture

continued northwards towards the Andaman and Nicobar Islands. However, the

northern rupture occurred more slowly than in the south, at about 2.1 km/s (1.3

mi/s) (7,500 km/h or 4,700 mph), continuing north for another five minutes to a

plate boundary where the fault type changes from subduction to strike-slip (the

two plates slide past one another in opposite directions).

The Indian Plate is part of the great Indo-Australian Plate, which

underlies the Indian Ocean and Bay of Bengal, and is drifting north-east at an

average of 6 centimeters per year (2.4 inches per year). The India Plate meets

the Burma Plate (which is considered a portion of the great Eurasian Plate) at the

Sunda Trench. At this point the India Plate sub ducts beneath the Burma Plate,

which carries the Nicobar Islands, the Andaman Islands, and northern Sumatra.

The India Plate sinks deeper and deeper beneath the Burma Plate until the

increasing temperature and pressure drive volatiles out of the sub ducting plate.

These volatiles rise into the overlying plate causing partial melting and the

formation of magma. The rising magma intrudes into the crust above and exits

the Earth's crust through volcanoes in the form of a volcanic arc. The volcanic

activity that results as the Indo-Australian Plate sub ducts the Eurasian Plate has

created the Sunda Arc.

As well as the sideways movement between the plates, the sea floor is

estimated to have risen by several meters, displacing an estimated 30 cubic

kilometers (7.2 cu mi) of water and triggering devastating tsunami waves. The

waves did not originate from a point source, as was inaccurately depicted in

some illustrations of their paths of travel, but rather radiated outwards along the

entire 1,600-kilometre (1,000 mi) length of the rupture (acting as a line source).

This greatly increased the geographical area over which the waves were

44

observed, reaching as far as Mexico, Chile, and the Arctic. The raising of the sea

floor significantly reduced the capacity of the Indian Ocean, producing a

permanent rise in the global sea level by an estimated 0.1 millimeters.

Aftershocks and other earthquakes:

The Researcher Propose that numerous aftershocks were reported off the

Andaman Islands, the Nicobar Islands and the region of the original epicenter in

the hours and days that followed. The magnitude 8.7 2005 Sumatra earthquake,

which originated off the coast of the Sumatran island of Nias, is not considered

an aftershock, despite its proximity to the epicenter, and was most likely

triggered by stress changes associated with the 2004 event. This earthquake was

so large that it produced its own aftershocks (some registering a magnitude of as

great as 6.1) and presently ranks as the 7th largest earthquake on record since

1900. Other aftershocks of up to magnitude 6.6 continued to shake the region

daily for up to three or four months. As well as continuing aftershocks, the

energy released by the original earthquake continued to make its presence felt

well after the event. A week after the earthquake, its reverberations could still be

measured, providing valuable scientific data about the Earth's interior.

The 2004 Indian Ocean earthquake came just three days after a

magnitude 8.1 earthquake in an uninhabited region west of New Zealand's

subantarctic Auckland Islands, and north of Australia's Macquarie Island. This is

unusual, since earthquakes of magnitude 8 or more occur only about once per

year on average. Some seismologists have speculated about a connection

between these two earthquakes, saying that the former one might have been a

catalyst to the Indian Ocean earthquake, as the two earthquakes happened on

opposite sides of the Indo-Australian Plate. However, the U.S. Geological

Survey sees no evidence of a causal relationship in this incident. Coincidentally,

the earthquake struck almost exactly one year (to the hour) after a 6.6 magnitude

earthquake killed an estimated 30,000 people in the city of Bam in Iran on 26

December 2003.

45

Some scientists confirm that the December earthquake had activated

Leuser Mountain, a volcano in Aceh province along the same range of peaks as

Mount Talang, while the 2005 Sumatra earthquake had sparked activity in Lake

Toba, an ancient crater in Sumatra. Geologists say that the eruption of Mount

Talang in April 2005 is connected to the December earthquake.

Energy released:

The Researcher Propose that the energy released on the Earth's surface

only (ME, which is the seismic potential for damage) by the 2004 Indian Ocean

earthquake and tsunami was estimated at 1.1×1017 joules, or 26 megatons of

TNT. This energy is equivalent to over 1500 times that of the Hiroshima atomic

bomb, but less than that of Tsar Bomb, the largest nuclear weapon ever

detonated. However, the total work done MW (and thus energy) by this quake

was 4.0×1022 joules (4.0×1029 ergs), the vast majority underground. This is

over 360,000 times more than its ME, equivalent to 9,600 gigatons of TNT

equivalent (550 million times that of Hiroshima) or about 370 years of energy

use in the United States at 2005 levels of 1.08×1020 J.

The earthquake generated a seismic wavering of the Earth's surface of up

to 20–30 cm (8–12 in), corresponding to the effect of the tidal forces caused by

the Sun and Moon. The shock waves of the earthquake were felt across the

planet; as far away as the U.S. state of Oklahoma, where vertical movements of

3 mm (0.12 in) were recorded. By February 2005, the earthquake's effects were

still detectable as a 20 µm (0.02 mm; 0.0008 in) complex harmonic oscillation

of the Earth's surface, which gradually diminished and merged with the

incessant free oscillation of the Earth more than 4 months after the earthquake.

Because of its enormous energy release and low split depth, the

earthquake generated remarkable seismic ground motions around the globe,

particularly due to huge Rayleigh (surface) elastic waves that exceeded 1 cm

(0.4 in) in vertical amplitude everywhere on Earth. The record section plot

below displays vertical displacements of the Earth's surface recorded by

46

seismometers from the IRIS/USGS Global Seismographic Network plotted with

respect to time (since the earthquake initiation) on the horizontal axis, and

vertical displacements of the Earth on the vertical axis (note the 1 cm scale bar

at the bottom for scale). The seismograms are arranged vertically by distance

from the epicenter in degrees. The earliest, lower amplitude, signal is that of the

compressional (P) wave, which takes about 22 minutes to reach the other side of

the planet (the antipode; in this case near Ecuador). The largest amplitude

signals are seismic surface waves that reach the antipode after about 100

minutes. The surface waves can be clearly seen to reinforce near the antipode

(with the closest seismic stations in Ecuador), and to subsequently encircle the

planet to return to the epicentral region after about 200 minutes. A major

aftershock (magnitude 7.1) can be seen at the closest stations starting just after

the 200 minute mark. This aftershock would be considered a major earthquake

under ordinary circumstances, but is dwarfed by the main shock.

The shift of mass and the massive release of energy very slightly altered

the Earth's rotation. The exact amount is not yet known, but theoretical models

suggest the earthquake shortened the length of a day by 2.68 microseconds, due

to a decrease in theoblateness of the Earth. It also caused the Earth to minutely

"wobble" on its axis by up to 2.5 cm (0.98 in) in the direction of 145° east

longitude, or perhaps by up to 5 or 6 cm (2.0 or 2.4 in). However, because of

tidal effects of the Moon, the length of a day increases at an average of 15 µs per

year, so any rotational change due to the earthquake will be lost quickly.

Similarly, the natural Chandler wobble of the Earth, which in some cases can be

up to 15 m (50 ft), will eventually offset the minor wobble produced by the

earthquake.

More spectacularly, there was 10 m (33 ft) movement laterally and 4–5

m (13–16 ft) vertically along the fault line. Early speculation was that some of

the smaller islands south-west of Sumatra, which is on the Burma Plate (the

southern regions are on the Sunda Plate), might have moved south-west by up to

36 m (120 ft), but more accurate data released more than a month after the

47

earthquake found the movement to be about 20 cm (8 in). Since movement was

vertical as well as lateral, some coastal areas may have been moved to below sea

level. The Andaman and Nicobar Islands appear to have shifted south-west by

around 1.25 m (4 ft 1 in) and to have sunk by 1 m (3 ft 3 in).

In February 2005, the Royal Navy vessel HMS Scott surveyed the

seabed around the earthquake zone, which varies in depth between 1,000 and

5,000 m (550 and 2,730 fathoms; 3,300 and 16,400 ft). The survey, conducted

using a high-resolution, multi-beam sonar system, revealed that the earthquake

had made a huge impact on the topography of the seabed. 1,500-metre-high

(5,000 ft) thrust ridges created by previous geologic activity along the fault had

collapsed, generating landslides several kilometers wide. One such landslide

consisted of a single block of rock some 100 m high and 2 km long (300 ft by

1.25 mi). The momentum of the water displaced by tectonic uplift had also

dragged massive slabs of rock, each weighing millions of tons, as far as 10 km

(6 mi) across the seabed. An oceanic trench several kilometres wide was

exposed in the earthquake zone.

The TOPEX/Poseidon and Jason-1 satellites happened to pass over the

tsunami as it was crossing the ocean. These satellites carry radars that measure

precisely the height of the water surface; anomalies of the order of 50 cm (20 in)

were measured. Measurements from these satellites may prove invaluable for

the understanding of the earthquake and tsunami. Unlike data from tide gauges

installed on shores, measurements obtained in the middle of the ocean can be

used for computing the parameters of the source earthquake without having to

compensate for the complex ways in which close proximity to the coast changes

the size and shape of a wave.

48

Chapter II: Concepts of Earthquake, Volcano & Tsunami

2.1 Concept of Earthquake:

The Researcher Propose that an earthquake is caused by a sudden slip on

a fault. Stresses in the earth's outer layer push the sides of the fault together.

Stress builds up and the rocks slips suddenly, releasing energy in waves that

travel through the earth's crust and cause the shaking that we feel during an

earthquake. An EQ occurs when plates grind and scrape against each other. In

California there are two plates the Pacific Plate and the North American Plate.

The Pacific Plate consists of most of the Pacific Ocean floor and the California

Coast line. The North American Plate comprises most the North American

Continent and parts of the Atlantic Ocean floor. This primary boundary between

these two plates is the San Andreas Fault. The San Andreas Fault is more than

650 miles long and extends to depths of at least 10 miles. Many other smaller

faults like the Hayward (Northern California) and the San Jacinto (Southern

California) branch from and join the San Andreas Fault Zone. The Pacific Plate

grinds northwestward past the North American Plate at a rate of about two

inches per year. Parts of the San Andreas Fault system adapt to this movement

by constant "creep" resulting in many tiny shocks and a few moderate earth

tremors. In other areas where creep is NOT constant, strain can build up for

hundreds of years, producing great EQs when it finally releases.

Earthquakes induced by human activity have been documented in a few

locations in the United States, Japan, and Canada. The cause was injection of

fluids into deep wells for waste disposal and secondary recovery of oil, and the

use of reservoirs for water supplies. Most of these earthquakes were minor. The

largest and most widely known resulted from fluid injection at the Rocky

Mountain Arsenal near Denver, Colorado. In 1967, an earthquake of magnitude

5.5 followed a series of smaller earthquakes. Injection had been discontinued at

the site in the previous year once the link between the fluid injection and the

earlier series of earthquakes was established. Other human activities, even

49

nuclear detonations, have not been linked to earthquake activity. Energy from

nuclear blasts dissipates quickly along the Earth's surface. Earthquakes are part

of a global tectonic process that generally occurs well beyond the influence or

control of humans. The focus (point of origin) of earthquakes is typically tens to

hundreds of miles underground. The scale and force necessary to produce

earthquakes are well beyond our daily lives. We cannot prevent earthquakes;

however, we can significantly mitigate their effects by identifying hazards,

building safer structures, and providing education on earthquake safety.

Interior of the Earth:

The Researcher Propose that five billion years ago the Earth was formed

by a massive conglomeration of space materials. The heat energy released by this

event melted the entire planet, and it is still cooling off today. Denser materials

like iron (Fe) sank into the core of the Earth, while lighter silicates (Si), other

oxygen (O) compounds, and water rose near the surface. The earth is divided into

four main layers: the inner core, outer core, mantle, and crust. The core is

composed mostly of iron (Fe) and is so hot that the outer core is molten, with

about 10% sulfur (S). The inner core is under such extreme pressure that it

remains solid. Most of the Earth's mass is in the mantle, which is composed of

50

iron (Fe), magnesium (Mg), aluminum (Al), silicon (Si), and oxygen (O) silicate

compounds. At over 1000 degrees C, the mantle is solid but can deform slowly in

a plastic manner. The crust is much thinner than any of the other layers, and is

composed of the least dense calcium (Ca) and sodium (Na) aluminum-silicate

minerals. Being relatively cold, the crust is rocky and brittle, so it can fracture in

earthquakes.

A fault is a fracture or zone of fractures between two blocks of rock.

Faults allow the blocks to move relative to each other. This movement may occur

rapidly, in the form of an earthquake - or may occur slowly, in the form of creep.

Faults may range in length from a few millimeters to thousands of kilometers.

Most faults produce repeated displacements over geologic time. During an

earthquake, the rock on one side of the fault suddenly slips with respect to the

other. The fault surface can be horizontal or vertical or some arbitrary angle in

between.

Earth scientists use the angle of the fault with respect to the surface

(known as the dip) and the direction of slip along the fault to classify faults. Faults

which move along the direction of the dip plane are dip-slip faults and described

as either normal or reverse, depending on their motion. Faults that move

horizontally are known as strike-slip faults and are classified as either right-lateral

51

or left-lateral. Faults, which show both dip-slip and strike-slip motion are known

as oblique-slip faults.

Normal fault- a dip-slip fault in which the block above the fault has

moved downward relative to the block below. This type of faulting occurs in

response to extension and is often observed in the Western United States Basin

and Range Province and along oceanic ridge systems.

Thrust fault- a dip-slip fault in which the upper block, above the fault

plane, moves up and over the lower block. This type of faulting is common in

areas of compression, such as regions where one plate is being sub ducted under

another as in Japan. When the dip angle is shallow, a reverse fault is often

described as a thrust fault.

Strike-slip fault - a fault on which the two blocks slide past one another.

The San Andreas Fault is an example of a right lateral fault.

A left-lateral strike-slip fault is one on which the displacement of the

far block is to the left when viewed from either side.

A right-lateral strike-slip fault is one on which the displacement of the

far block is to the right when viewed from either side.

Earthquakes occur on faults - strike-slip earthquakes occur on strike-slip

faults, normal earthquakes occur on normal faults, and thrust earthquakes occur

on thrust or reverse faults. When an earthquake occurs on one of these faults, the

rock on one side of the fault slips with respect to the other. The fault surface can

be vertical, horizontal, or at some angle to the surface of the earth. The slip

direction can also be at any angle.

52

Earthquake stress transfer:

The Researcher Propose that the state of stress on a fault is a key factor

used to determine if rupture is imminent. A common view is that once an

earthquake has occurred and released stress on a fault, the fault will remain quiet

until stresses in the Earth‘s crust have time to rebuild, typically over hundreds to

thousands of years. Probabilistic earthquake catastrophe models follow this

concept, which is known as the seismic cycle. The mean return period depends on

the long-term rate of tectonic stress loading t/ t, which is usually assumed

constant; the failure stress f; and the earthquake stress drop 0. Variations in the

stress drop lead to some deviations from mean return period, a concept known as

aperiodicity. In practice, event probabilities are directly determined from the

recurrence of past earthquakes by using statistical approaches, such as the Poisson

process method or a time-dependent renewal model. In the Poissonian approach,

the odds of an earthquake do not change with time, whereas in the renewal model

approach, the odds increase with time based on the time since the last event.

An important discovery made in the mid-1990s1 was that the stress

released on a fault during an earthquake does not simply dissipate; instead, it

moves down the fault and concentrates in sites nearby, typically at the tips of the

rupture. On nearby faults, at distances of kilometers to hundreds of kilometers, the

effect is an increase in stress. This stress jump will displace the one due to

tectonic stress loading assumed in the seismic cycle. Although the stress increase

may be small (typically less than or equal to about 1% of the stress released in the

initial earthquake), its effects can be significant. Note that a decrease of stress

would have the opposite effect, possibly delaying the next earthquake, a

phenomenon known as quiescence. These increases and decreases in stress along

a fault are described by the stress transfer theory. Positive stress transfer (i.e., an

increase in stress) can temporally modify a fault‘s seismic cycle and advance the

next earthquake by a time period.

1 Reasenberg and Simpson, 1992; King et al., 1994

53

Earthquake interaction in Turkey:

The Researcher Propose that the North Anatolian Fault in Turkey is a

major active strike-slip fault along the boundary between the Eurasian Plate and

the Anatolian Plate. It is among the world‘s most heavily populated fault zones

and an ideal case study for earthquake clustering and propagating rupture

sequences. Earthquakes have been shown to jump from one fault segment to

another from the east end to the west end of the fault, starting in 1939 and ending

in a series of two events in 1999. As shown in Figure 4, an additional earthquake

occurred on the Marmara Fault system in 1912, but this event was not part of the

sequence.

The 1999 Clustered Events:

The Researcher Propose that the two most recent and destructive

earthquakes in Turkey occurred on the North Anatolian Fault in 1999. The

magnitude (M) 7.6 Izmit Earthquake, also known as the Kocaeli Earthquake,

occurred on August 17, 1999. Only three months later, the M7.2 Düzce

Earthquake struck 110 km (68 mi) to the east on November 12, 1999. The series

of earthquakes caused close to 19,000 fatalities with over 48,000 hospitalized

injuries1. At the time, the population in the area affected by the two earthquakes

was about 20 million, one-third of the population of the entire country.

Furthermore, almost one-half of the Turkish economic infrastructures are located

in this region2. Insurance loss estimates following the Kocaeli Earthquake were

approximately US$2 billion (in 1999 dollars)3. The Kocaeli Earthquake affected

residential parts and city centers of many towns, in particular Izmit but also

Düzce, which was then devastated by the second event a few months later.

Using the example of the 1999 Kocaeli and Düzce earthquake cluster,

Figure 6 illustrates the principle of stress interactions. The net stress changes due

1 Erdik, 2000

2 Sahin and Tari, 2000

3 Swiss Re, 2000

54

to the 1999 Kocaeli Earthquake are represented in red for a stress increase and in

purple for a stress decrease. The Düzce Earthquake occurred three months later in

a region of increased stress, as predicted by the theory of stress transfer. For the

whole Turkey and Aegean region, it has been shown that the majority of large

earthquakes since the start of the 19th century (>30 events) occurred in regions of

increased stress and none have occurred in regions of clear decreased stress1.

Seismic Hazard in the Istanbul Region:

The Researcher Propose that following the 1999 earthquake events, the net

positive stress changes migrated to the ends of the fault. Arguably, the increase in

stress along the Marmara Fault system, which is just south of the city of Istanbul,

has increased the risk for the city2 an urban center of 10 million inhabitants. The

present-day stress conditions in this region, computed using the most recent data

available3. An accurate knowledge of the historical earthquake record in the

region, including well-resolved ruptures for the 1894, 1912, and 1999 events, in

combination with the secular loading stress, gives a realistic view of the present-

day seismic hazard near Istanbul.

The quantification of the net stress changes due to a recent earthquake is

crucial to determine the risk linked to clustering. However, a new earthquake will

only be triggered if the fault is already sufficiently loaded (i.e., late in its seismic

cycle). The current state of loading on the fault can only be assessed with the

knowledge of the fault history and of the secular rate of the tectonic stress

loading. The North Anatolian Fault (plus the Marmara Fault system in the Sea of

Marmara) is therefore one of the most appropriate on Earth to determine

earthquake interactions. Reliable information covers almost two seismic cycles

(i.e., over the past 500 years or so), providing a unique opportunity to quantify the

actual state of stress of the region.

1 Nalbant et al., 2002; Nalbant et al., 1998; Stein et al., 1997; Parsons et al., 2000; Hubert -Ferrari et al., 2000

2 Parsons et al., 2000; Hubert-Ferrari et al., 2000,

3 Armijo et al., 2005

55

Records kept during the Ottoman Empire provide accurate descriptions of

earthquake damage that date back to the start of the 16th century. Today, more

details on fault history are available through new field studies (e.g., discovery of

submarine fault scarps in the Sea of Marmara using a remote operated vehicle)

and proposed models of secular stress loading based on geodetic data sets (e.g. ,

from GPS data).

A team from the U.S. Geological Survey quantified the seismic hazard in

Istanbul using a model that incorporated stress interactions1. Based on the Poisson

approach, they found a 15 to 25% chance of an earthquake damaging the city

from 2000 through 2030. However, because the major faults of the Istanbul region

are likely late in their seismic cycles, the probability increases to nearly 50±15%

based on the renewal model of earthquake recurrence. Furthermore, with the

increase of stress due to the 1999 Kocaeli Earthquake, the interaction-based

probability is over 60±15%.

Earthquake interactions in Indonesia:

The Researcher Propose that the M9.3 Indian Ocean Earthquake that was

initiated off the coast of Sumatra and the Andaman Islands on December 26, 2004

is best known for its devastating tsunami, which propagated across the entire

Indian Ocean basin. According to the U.S. Geological Survey, if both the direct

and indirect effects of the earthquake are taken into account, this event was the

fourth deadliest earthquake in recorded history, behind the 1556 Huaxian

Earthquake in China, the 1976 Tangshan Earthquake in China2, and 1138 Aleppo

Earthquake in Syria2. Only three months later on March 28, 2005, a second major

event, the M8.7 Nias Earthquake, struck just south of the 2004 rupture, causing

more than 1,000 casualties. A tsunami was again generated, this time only causing

minor damage in the far-field. Since then, several other large (M>7) and deadly

earthquakes have occurred along the Sumatra subduction zone, also known as the

Sunda Trench.

1 Parsons et al., 2000

2 U.S. Geological Survey, 2008

56

Smaller events (M<7) occurring on the Sumatran Fault, a large onshore

transform (strike-slip) fault running north to south on Sumatra Island, can also

have disastrous consequences due to the proximity of this fault to major

population centers. Figure 9 illustrates the tectonics of the region, as well as the

population density throughout Sumatra and the northern end of Java.

The 2004 and 2005 Clustered Events:

The Researcher Propose that insured property losses from the 2004 Indian

Ocean Earthquake and Tsunami were approximately US$5 billion (in 2004

dollars)1. The earthquake-induced tsunami particularly affected the Indonesian

province of Aceh. The second clustered event occurred three months afterward in

March 2005, about 200 km (124 mi) south of the first event, causing widespread

power outages and more damage in regions already devastated by the first

earthquake and tsunami. In particular, Nias Island, which was partially destroyed

by the 2004 earthquake and tsunami, was in close proximity to the epicenter of

the March 2005 event. As a result, when the 2005 earthquake struck, it did even

more damage in the southwest part of this island than the 2004 event.

Changes in Seismic Hazard since 2004:

The Researcher Propose that Table A lists some of the deadly earthquakes

along the Sunda Trench and Sumatran Fault between 2004 and 2008.3 Events on

the Sunda Trench, or Sumatra subduction zone, are generated by thrust faulting

and able to produce tsunamis, while events on the Sumatran Fault are generated

onshore by strike-slip faulting. Although events on the Sumatran Fault are 1 to 2

magnitude units smaller than subduction earthquakes, they are also able to

produce significant damage, such as the March 6, 2007 event, which killed 70

people.

1 Swiss Re, 2004

57

Table A. Deadly earthquakes in the Sumatra region between 2004 and 20081

Date Magni

tude

Fault Potential

Stress

Triggered

Event?

Fatalities

December 26, 2004 9.3 Sunda Trench No 283,105*

March 28, 2005 8.7 Sunda Trench Yes 1,315

July 17, 2006 7.7 Sunda Trench No 730

March 6, 2007 6.4 Sumatran

Fault

Yes 70

September 12, 2007 8.4;

7.9

Sunda Trench No 25

February 20, 2008 7.4 Sunda Trench Yes 3

The net stress increase on the Sumatra subduction zone and the Sumatran

Fault resulting from the four largest earthquakes (M>7) that occurred in the

region between 2004 and 2007 (see Table 1) is represented on Figure 12. The

net stress increase is shown at three different times: December 2004, July 2006,

and February 2008. The events are chronicled below.

December 2004–February 2005:

The Researcher Propose that the M9.3 Indian Ocean Earthquake occurs,

relaxing stress along a consequent part of the Sumatra subduction zone and

increasing stress southward2 and on the north part of the Sumatran Fault

3. The

rupture extent of the future March 28, 2005 M8.7 event is outlined in black just

south of the 2004 rupture, and its northern end is located in a region of increased

stress. Field observations made before 2006 along the Sunda Trench (off the

west coast of central Sumatra), show that this portion of the subduction zone is

near the end of its seismic cycle4. It suggests that this part of the subduction

zone is ready to rupture because of the long-term tectonic loading.

1 Source: USGS— http://earthquake.usgs.gov/regional/world/historical_country_mag.php#indonesia

2 McCloskey et al., 2005; Pollitz et al., 2006

3 McCloskey et al., 2005

4 McCloskey et al., 2005

58

March 2005–July 2006:

The Researcher Propose that the March 2005 Nias Earthquake (M8.7)

occurs only three months after the 2004 event in a region of increased stress,

with its epicenter approximately 189 km (117 mi) south of the 2004 event.

Stresses imposed by this second rupture have brought the thrust segment

immediately to the south closer to failure and have expanded the area of

increased stress on the Sumatran Fault1. Another event (M7.7) occurs south of

Sumatra along the subduction zone in July 2006. However, there was no

evidence of stress transfer and the degree of stress loading on the fault segment

was unknown.

August 2006–February 2008:

The Researcher Propose that a M6.4 earthquake occurs in March 2007

on the Sumatran Fault in a region where the stress has been increased by the

M8.7 2005 Nias event. Two subsequent earthquakes (M8.4 and M7.9) occur in

September 2007 in the middle of the seismic gap of the Sumatra subduction

zone (i.e., locked segment that has not experienced seismic activity for a long

time). There were observations that the tectonic stress loading at the location of

these two large earthquakes matched the stress released during the events of

1797 and 18332. Then, in February 2008, a M7.4 earthquake struck at the

boundary between the 2004 and 2005 rupture zones on the subduction zone. It is

unclear whether this earthquake occurred in a region of increased stress or in a

region relaxed since March 2005, as assumed in the map in Figure 12, where the

continuous blue coloring indicates fault rupture across entire length of the

subduction zone.

The fact that no seismic gap seemed to remain between the events of

December 2004 and March 2005 would suggest that all the stress was released

in this region. However, fault heterogeneities, such as bends, can lead to local

stress perturbations. In such a case, the February 2008 event might have been a

1 Nalbant et al., 2005

2 Natawidjaja et al., 2006; Nalbant et al., 2005

59

result of stress concentration, although this process is highly difficult to

quantify.

At present, two distinct segments of the Sumatra subduction zone are

highly stressed due to stress transfer and could generate M>7.5 earthquakes. The

northern and southern parts of the Sumatran Fault are also stressed and could

potentially produce clustered events in the range of M6–7.1

Earthquake interaction in the New Madrid:

The Researcher Propose that another well-known example of earthquake

clustering is the case of the New Madrid earthquake sequence that occurred in

the Central U.S. in late 1811 and early 1812. Over the span of two months, four

M>7 earthquakes occurred along the faults bordering the states of Arkansas,

Tennessee, Kentucky, Missouri, and Illinois. The first event, which occurred on

December 16, 1811 with an estimated magnitude of 7.2–8.1, and the last event,

which occurred on February 7, 1812 with an estimated magnitude of 7.5–8.0, are

believed to have ruptured two fault zones defined by modern seismicity: the

northeast-striking Cottonwood Grove Fault and the west-dipping Reel foot

thrust fault, respectively. The second earthquake was the smallest of the

sequence, occurring the same day as the first one on December 16, 1811 with a

magnitude of 7.0—this event may have been an aftershock, or may have

occurred on a separate fault. The third earthquake of M7.0–7.8 struck on

January 23, 1812 and has been interpreted in two ways: as a strike-slip rupture

on the Northeast Arm of the New Madrid Seismic Zone, or a remotely triggered

event that occurred outside of the New Madrid Seismic Zone2.

Although the 1811–1812 earthquake sequence changed the course of the

Mississippi River and destroyed entire forests, fatalities and damage to

infrastructures were low because the area was sparsely settled in the early 19th

century. The present-day population in the New Madrid region, however,

includes the cities of Memphis, Jackson, Jonesboro, and Cape Girardeau. If this

1 list of Indonesian earthquakes, see http://earthquake.usgs.gov/regional/world/historical_count ry_mag.php#indonesia

2 Mueller et al., 2004

60

earthquake sequence occurred today, it would have devastating consequences.

An analysis conducted by RMS indicates that a repeat of the February 7, 1812

event alone would cause over US$115 billion in insured losses to the

surrounding region1.

Scenarios of Clustered Events:

The Researcher Propose that the actual impact of the 1811–1812

earthquake sequence is still poorly understood. In particular, the January 23,

1812 event had few documented eyewitness accounts. Furthermore, since this

time, there has not been a significant event on these faults. Due to the lack of

historical information, one way to assess the current seismic hazard in the New

Madrid Seismic Zone based on interaction-based methods is to test different

stress transfer scenarios, as illustrated in Figure 16. Since return periods in such

an intra-plate environment are long approximately 550 to 1,100 years2 a

Poissonian approach to earthquake recurrence clearly cannot explain a

succession of four M>7 earthquakes striking in a two-month period as observed

in 1811 and 1812. It should be noted, however, that pale liquefaction data in the

New Madrid region suggests a return period of only 500 years in this area.

By taking into account all known faults in the New Madrid Seismic

Zone, interaction-based models show that a series of two events and a series of

three events are possible in many ways. For example, based on the theory of

stress transfer, there is a clear interaction between the Cottonwood Grove Fault

and the Reel foot thrust fault that most likely led to the 1811–1812 cluster

sequence.

In certain active tectonic regions of the world, it is possible to illustrate

how interaction-based earthquake recurrence models fit nicely to the observed

historical record. For example, the 1999 M>7 events in Izmit and Düzce,

Turkey, and the 2004–2005 M>8 events in the Indian Ocean are good examples

of the triggering of earthquakes due to stress interactions. Furthermore, the

1 Hall et al., 2006

2 Wesnousky et al., 1992

61

theory of stress transfer can be used in probabilistic earthquake catastrophe

models to quantify the risk associated with spatio-temporal clustering. Different

scenarios of clustered events can be explored, such as in the New Madrid

Seismic Zone in the Central U.S., which lead to new alternatives for earthquake

risk assessment.

62

2.2 Concept of Volcano:

The Researcher Propose that a volcano is a vent or an opening on the

surface of the earth‘s crust that allows hot magma, volcanic ashes and gases to

escape from below the earth‘s surface.

Volcanoes are mostly found where the tectonic plates are diverging or

converging. Tectonic plates are nothing but the large scale motion of earth‘s

lithosphere. Volcanoes can also form at places where the earth‘s crust is thin and

stretched.

Origin of name:

The word volcano has its origin from the little island of Vulcano in the

Mediterranean Sea off Sicily. Centuries ago, people residing this area believed

that Vulcano was the chimney of the forge of Vulcan (Lat. Volcanus)--the

blacksmith of the Roman gods.

Types of volcanoes:

The Researcher Propose that depending on the frequency of eruption of

the volcanoes they are categorized as:

Active volcanoes: These are the ones that are still alive and erupt

frequently. For example: Barren Island in the Andaman sea.

Dormant volcanoes: These are the ones that have erupted in historical

times and are quiet now. For example: Mauna Kea, one of the five volcanoes that

make the big island of Hawaii.

Extinct volcanoes: According to the scientists the volcanoes that are

unlikely to erupt again, because the volcano no longer has a lava supply are

termed as extinct volcano. For example: the volcanoes on the Hawaiian –

Emperor Seamount chain in the Pacific Ocean

Geologists however group volcanoes into four main kinds:

Cinder cones,

Composite volcanoes,

63

Shield volcanoes, and

Lava domes.

Geophysical hazards: volcanic eruptions

The Researcher Propose that volcanic eruptions happen when lava and gas

are discharged from a volcanic vent. The most common consequences of this are

population movements as large numbers of people are often forced to flee the

moving lava flow. Volcanic eruptions often cause temporary food shortages and

volcanic ash landslides called Lahar.The most dangerous type of volcanic

eruption is referred to as a 'glowing avalanche'. This is when freshly erupted

magma forms hot pyroclastic flow which has temperatures of up to 1,200 degrees.

The pyroclastic flow is formed from rock fragments following a volcanic

explosion, the flow surges down the flanks of the volcano at speeds of up to

several hundred kilometers per hour, to distances often up to 10km and

occasionally as far as 40 km from the original disaster site.

The International Federation response adjusts to meet the needs of each

specific circumstance. As population movement is often a consequence, the

provision of safe areas, shelter, water, food and health supplies are primordial.

In general response prioritizes temporary shelter materials; safe water and basic

sanitation; food supplies; and the short term provision of basic health services

and supplies.

Plate Volcanoes - The majority of volcanoes are formed when two of the

Earth‘s plates meet and collide. These volcanoes actually occur on the ocean

floor.

If the amount of magma is significant enough, then the magma rises above

the surface of the ocean. This is known as an island. When the two plates collide

and one plate forces the other plate beneath it, a different reaction occurs.

If this happens, then the friction that is caused during this reaction makes

the plate melt that is beneath the other plate. This then causes magma to rise up,

64

and this creates a volcano. The volcanoes that form by this method are usually the

most dangerous and the most volatile ones.

Shield Volcanoes - Shield volcanoes are extremely broad and flat when

compared to other volcanoes.

Their shape is created by a significant amount of lava running down the

surface of the volcano, and then cooling. The eruptions of shield volcanoes aren‘t

as severe as other volcanoes. When a shield volcano erupts, gases escape and the

lava rise to the surface to gently flow down the sides of the volcano.

Composite Volcanoes - Composite volcanoes, also known as strato-

volcanoes, are formed by alternate layers of rock fragments and lava. The shape

of a composite volcano is large and cone-like.

Caldera Volcanoes - Caldera volcanoes are formed from considerable

amounts of magma erupting from sub-surface magma chambers. When the

magma erupts, it leaves an empty space below the surface. The eruption of a

caldera volcano generally has the coolest lava; but, they are the most dangerous

because their eruption might also cause tsunamis, large pyroclastic surges, and

widespread falling of ash.

Decade Volcanoes - These volcanoes are sixteen volcanoes that have been

identified by scientists as noteworthy due to their large eruptions, and their

closeness to populated areas. They include: Avachinsky-Koryaksky in Russia,

Nevado de Colima in Mexico, Mount Etna in Italy, Galeras in Colombia, Mauna

Loa in the United States, Mount Merapa in Indonesia, Mount Nyiragongo in

Africa, Mount Rainer in the United States, Sakurajima in Japan, Santa Maria in

Guatemala, Santorini in Greece, Taal Volcano in the Philippines, Teide in Spain,

Ulawun in New Britain, Mount Unzen in Japan, and Mount Vesuvius in Italy.

65

Origin of Volcano:

The Researcher Propose that volcanoes are one of the most dynamic,

powerful, and visible forces on Earth. What are volcanoes and what factors

cause them to form in certain areas? How are geothermal features like fumaroles

and geysers related to these temperamental mountains?

Let us start by looking at the volcano itself and learn the different parts

of it, the rocks associated with it, and where volcanoes form.

Form of Volcano:

The Researcher Propose that hot magma, melted rock below Earth's

crust, rises and collects in a magma chamber deep below the surface. If the

magma flows through a conduit up to a vent on the surface, then it may cause an

eruption and form a volcano.

Gases, lava, and pyroclastic material are erupted from volcanic vents.

The mountain that forms from layers of lava and tephra is called a volcano. The

word "volcano" comes from the name of a Roman god, Vulcan, who was the

god of fire. Magma that solidifies inside a volcano can form dikes and sills.

Volcanoes are classified as active, dormant or extinct.

The Magma Chamber:

The Researcher Propose that magma is the name given to melted liquid

rock below Earth's surface. It is stored below the volcano in a chamber or

reservoir. During active periods, this reservoir fills with magma. After a large

eruption, or during dormancy, this reservoir can drain, which may trigger the

creation of a caldera.

66

The Magma Conduit:

The Researcher Propose that the magma conduit is the plumbing system

of the volcano. Molten magma creates ―pipes‖, through the volcano. Magma

then travels through them to the surface.

The Main Vent:

The Researcher Propose that the main vent often is located at or near the

summit of the volcano. This is where most eruptive activity (lava flows,

pyroclastic flows, and large gas emissions) occurs.

Lava Flows:

The Researcher Propose that Lava flows occur during some eruptions.

Once magma reaches the vent and flows onto the surface of Earth it is called

lava. Lava flows add land to the surface, and build the mountains we call

volcanoes. The island of Hawaii is nearly 100% cooled and solidified lava!

Pyroclastic Flows:

The Researcher Propose that pyroclastic flows occur during some

eruptions. These are super-heated clouds of volcanic material ranging from ash

to volcanic bombs. Pyroclastic flows travel very fast, and can destroy everything

in their path.

The Volcano:

The Researcher Propose that volcanoes are built from layers of lava and

tephra (particles of rock, solidified lava, and ash of all different sizes). The lava

cools on the sides of the volcano and hardens into rock. Pyroclastic flows and

eruption clouds deposit tephra on top of lava layers, increasing the size of the

mountain.

67

Dikes and Sills:

The Researcher Propose that the molten, pressurized magma intrudes

into the solid volcanic rock to create dikes and sills. Dikes cut across volcanic

rock layers, and sills run parallel to the layers. Eventually the magma hardens

inside Earth and becomes an intrusive igneous rock.

Vulcan, Roman God of Fire:

The Researcher Propose that in Roman mythology, Vulcan was the god

of fire. He was also known as the blacksmith of the gods.

There is a small volcanic island in the Mediterranean Sea called

Vulcano. The local residents once believed the volcano on the island was the

chimney of Vulcan's workshop. They thought the hot lava and smoke issuing

from the mountain were products of Vulcan's work as he created thunderbolts

for Jupiter, king of the gods, and weapons for Mars, god of war.

Active, Dormant, and Extinct:

The Researcher Propose that volcanologists classify volcanoes based on

how much activity has been recorded over time.

Active:

The Researcher Propose that an active volcano is currently erupting or

has erupted in recent history. Active volcanoes can have eruptions of gases,

pyroclastic material, tephra, and lava.

Dormant:

The Researcher Propose that a dormant volcano is not presently erupting,

and has not erupted in recent history. There is still potential for renewed activity,

because there still may be magma moving or cooling deep inside the volcano.

68

Extinct:

The Researcher Propose that an extinct volcano has not erupted in recent

history and is unlikely to erupt again. Wind and water have broken and

smoothed the shape of the mountain. The magma has drained below the surface

or cooled inside the volcano.

Magma:

The Researcher Propose that magma is the word used to describe melted

or molten rock inside Earth. Magma is composed of elements, minerals, and

gases that were present in the rock before it melted.

The major elements in magma are those present in Earth's crust: oxygen

(O), silicon (Si), aluminum (Al), iron (Fe), calcium (Ca), sodium (Na),

magnesium (Mg), and potassium (K). These elements combine to form minerals

such as magnetite, hauynite, olivine, pyroxene, hornblende, plagioclase,

potassium feldspar (k-feldspar), and quartz.

Magma also contains dissolved gases like water vapor (H2O), carbon

dioxide (CO2), and sulfur dioxide (SO2).

Composition of Magma:

The Researcher Propose that the composition of the magma determines

the eruption style, rock type, and volcano shape. Variations in the chemical

compositions and properties of the magma determine whether it will be

classified as mafic, felsic, or intermediate.

69

2.3 Concept of Tsunami:

The Researcher Propose that Tsunami is a series of ocean waves typically

caused by large undersea earthquakes or volcano eruptions at tectonic plate

boundaries. These surges of water may reach 100 feet and cause widespread

destruction when they crash ashore. They race across the sea at a speed up to 500

miles per hour and cross the entire Pacific Ocean in less than one day. Their long

wavelength means that they lose very little energy along the way.

Tsunami of December 2004, caused by a 9.0 magnitude earthquake, is the

most infamous tsunami of modern times with disastrous consequences in many

areas humanitarian toll: it affected more than 18 countries from Southeast Asia to

Southern Africa, killing more than 250,000 people in a single day and leaving

more than one million homeless,(ii)economic toll: it left several million of dollars

of economic loss affecting fishing and tourist industries,(iii)environmental and

medical threats including water pollution and flooding and endemic diseases.

The rationale for writing this paper is to report the tsunami events in the

eleven nations bordering the Indian Ocean, as they received less publicity than

their Southeast Asian countries counterpart although the 2004 tsunami had real

humanitarian, economic, and environmental impact in these regions more than

1,000 miles away from the epicenter.

Furthermore, these regions are at risk from the devastating effects of

future tsunami due to the presence of a tectonic interactive plate, absence of a

tsunami warning system in the Indian Ocean, and lack of established

communication network providing timely information to that region.

70

Origin of Tsunami:

• Tsunamis are generated by any large, impulsive displacement of the sea bed

level.

• Earthquakes generate tsunamis by vertical movement of the sea floor. If the sea

floor movement is horizontal, a tsunami is not generated. Earthquakes of M 6.5

are critical for tsunami generation.

• Tsunamis are also triggered by landslides into or under the water surface, and

can be generated by volcanic activity and meteorite impacts.

Occurrences of Tsunami:

• On the average, there are two tsunamis per year somewhere in the world which

cause damage near the source.

• Approximately every 15 years a destructive, Pacific-wide tsunami occurs.

• The destructive tsunami on Dec 26th, 2004 on the Indian Coast seems to have

occurred for the first time in the history.

Travel of Tsunami:

• Tsunami velocity is dependent on the depth of water through which it travels.

• Tsunamis travel approximately 700 kmph in 4000 m depth of sea water. In 10

m of water depth the velocity drops to about 36 kmph.

• For example, the tsunami from Sumatra coastal earthquake traveled to Tamil

Nadu coast in about two hours.

• Even on shore tsunamis can faster than a person can run.

71

Size of Tsunami:

• Tsunamis range in size from centimeters to over 30 m height. Most tsunamis

are less than 3 m in height.

• In deep water (greater than 200 m), tsunamis are rarely over 1m high and will

not be noticed by ships due to their long period (time between crests).

• As tsunamis propagate into shallow water, the wave height can increase by

over 10 times.

• Tsunami heights can vary greatly along a coast. The waves are amplified by

certain shoreline and bathymetric (sea floor) features.

• A large tsunami can flood land up to more than 1.5 km from the coast.

• The force of some tsunamis is enormous. Large rocks weighing several tons

along with boats and other debris can be moved inland hundreds of feet by

tsunami wave activity. Homes and other buildings are destroyed. All this

material and water move with great force and can kill or injure people.

Tectonic plates:

The Researcher Propose that the mega thrust earthquake was unusually

large in geographical and geological extent. An estimated 1,600 kilometers

(1,000 mi) of fault surface slipped (or ruptured) about 15 meters (50 ft) along

the subduction zone where the Indian Plate slides (or sub ducts) under the

overriding Burma Plate. The slip did not happen instantaneously but took place

in two phases over a period of several minutes:

Seismographic and acoustic data indicate that the first phase involved a

rupture about 400 kilometers (250 mi) long and 100 kilometers (60 mi) wide,

located 30 kilometers (19 mi) beneath the sea bed—the largest rupture ever

known to have been caused by an earthquake. The rupture proceeded at a speed

72

of about 2.8 kilometers per second (1.7 miles per second) (10,000 km/h or 6,200

mph), beginning off the coast of Aceh and proceeding north-westerly over a

period of about 100 seconds.

A pause of about another 100 seconds took place before the rupture

continued northwards towards the Andaman and Nicobar Islands. However, the

northern rupture occurred more slowly than in the south, at about 2.1 km/s (1.3

mi/s) (7,500 km/h or 4,700 mph), continuing north for another five minutes to a

plate boundary where the fault type changes from seduction to strike-slip (the

two plates slide past one another in opposite directions).

The Indian Plate is part of the great Indo-Australian Plate, which

underlies the Indian Ocean and Bay of Bengal, and is drifting north-east at an

average of 6 centimeters per year (2.4 inches per year). The India Plate meets

the Burma Plate (which is considered a portion of the great Eurasian Plate) at the

Sunda Trench. At this point the India Plate sub ducts beneath the Burma Plate,

which carries the Nicobar Islands, the Andaman Islands, and northern Sumatra.

The India Plate sinks deeper and deeper beneath the Burma Plate until the

increasing temperature and pressure drive volatiles out of the sub ducting plate.

These volatiles rise into the overlying plate causing partial melting and the

formation of magma. The rising magma intrudes into the crust above and exits

the Earth's crust through volcanoes in the form of a volcanic arc. The volcanic

activity that results as the Indo-Australian Plate sub ducts the Eurasian Plate has

created the Sunda Arc.

As well as the sideways movement between the plates, the sea floor is

estimated to have risen by several meters, displacing an estimated 30 cubic

kilometers (7.2 cu mi) of water and triggering devastating tsunami waves. The

waves did not originate from a point source, as was inaccurately depicted in

some illustrations of their paths of travel, but rather radiated outwards along the

entire 1,600-kilometre (1,000 mi) length of the rupture (acting as a line source).

This greatly increased the geographical area over which the waves were

73

observed, reaching as far as Mexico, Chile, and the Arctic. The raising of the sea

floor significantly reduced the capacity of the Indian Ocean, producing a

permanent rise in the global sea level by an estimated 0.1 millimeters.

Aftershocks and other earthquakes:

The Researcher Propose that numerous aftershocks were reported off the

Andaman Islands, the Nicobar Islands and the region of the original epicenter in

the hours and days that followed. The magnitude 8.7 2005 Sumatra earthquake,

which originated off the coast of the Sumatran island of Nias, is not considered

an aftershock, despite its proximity to the epicenter, and was most likely

triggered by stress changes associated with the 2004 event. This earthquake was

so large that it produced its own aftershocks (some registering a magnitude of as

great as 6.1) and presently ranks as the 7th largest earthquake on record since

1900. Other aftershocks of up to magnitude 6.6 continued to shake the region

daily for up to three or four months. As well as continuing aftershocks, the

energy released by the original earthquake continued to make its presence felt

well after the event. A week after the earthquake, its reverberations could still be

measured, providing valuable scientific data about the Earth's interior.

The 2004 Indian Ocean earthquake came just three days after a

magnitude 8.1 earthquake in an uninhabited region west of New Zealand's

subantarctic Auckland Islands, and north of Australia's Macquarie Island. This is

unusual, since earthquakes of magnitude 8 or more occur only about once per

year on average. Some seismologists have speculated about a connection

between these two earthquakes, saying that the former one might have been a

catalyst to the Indian Ocean earthquake, as the two earthquakes happened on

opposite sides of the Indo-Australian Plate. However, the U.S. Geological

Survey sees no evidence of a causal relationship in this incident. Coincidentally,

the earthquake struck almost exactly one year (to the hour) after a 6.6 magnitude

earthquake killed an estimated 30,000 people in the city of Bam in Iran on 26

December 2003.

74

Some scientists confirm that the December earthquake had activated

Leuser Mountain, a volcano in Aceh province along the same range of peaks as

Mount Talang, while the 2005 Sumatra earthquake had sparked activity in Lake

Toba, an ancient crater in Sumatra. Geologists say that the eruption of Mount

Talang in April 2005 is connected to the December earthquake.

Energy released:

The Researcher Propose that the energy released on the Earth's surface

only (ME, which is the seismic potential for damage) by the 2004 Indian Ocean

earthquake and tsunami was estimated at 1.1×1017 joules, or 26 megatons of

TNT. This energy is equivalent to over 1500 times that of the Hiroshima atomic

bomb, but less than that of Tsar Bomb, the largest nuclear weapon ever

detonated. However, the total work done MW (and thus energy) by this quake

was 4.0×1022 joules (4.0×1029 ergs), the vast majority underground. This is

over 360,000 times more than its ME, equivalent to 9,600 gigatons of TNT

equivalent (550 million times that of Hiroshima) or about 370 years of energy

use in the United States at 2005 levels of 1.08×1020 J.

The earthquake generated a seismic wavering of the Earth's surface of up

to 20–30 cm (8–12 in), corresponding to the effect of the tidal forces caused by

the Sun and Moon. The shock waves of the earthquake were felt across the

planet; as far away as the U.S. state of Oklahoma, where vertical movements of

3 mm (0.12 in) were recorded. By February 2005, the earthquake's effects were

still detectable as a 20 µm (0.02 mm; 0.0008 in) complex harmonic oscillation

of the Earth's surface, which gradually diminished and merged with the

incessant free oscillation of the Earth more than 4 months after the earthquake.

Because of its enormous energy release and low split depth, the

earthquake generated remarkable seismic ground motions around the globe,

particularly due to huge Rayleigh (surface) elastic waves that exceeded 1 cm

(0.4 in) in vertical amplitude everywhere on Earth. The record section plot

below displays vertical displacements of the Earth's surface recorded by

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seismometers from the IRIS/USGS Global Seismographic Network plotted with

respect to time (since the earthquake initiation) on the horizontal axis, and

vertical displacements of the Earth on the vertical axis (note the 1 cm scale bar

at the bottom for scale). The seismograms are arranged vertically by distance

from the epicenter in degrees. The earliest, lower amplitude, signal is that of the

compressional (P) wave, which takes about 22 minutes to reach the other side of

the planet (the antipode; in this case near Ecuador). The largest amplitude

signals are seismic surface waves that reach the antipode after about 100

minutes. The surface waves can be clearly seen to reinforce near the antipode

(with the closest seismic stations in Ecuador), and to subsequently encircle the

planet to return to the epicentral region after about 200 minutes. A major

aftershock (magnitude 7.1) can be seen at the closest stations starting just after

the 200 minute mark. This aftershock would be considered a major earthquake

under ordinary circumstances, but is dwarfed by the main shock.

The shift of mass and the massive release of energy very slightly altered

the Earth's rotation. The exact amount is not yet known, but theoretical models

suggest the earthquake shortened the length of a day by 2.68 microseconds, due

to a decrease in theoblateness of the Earth. It also caused the Earth to minutely

"wobble" on its axis by up to 2.5 cm (0.98 in) in the direction of 145° east

longitude, or perhaps by up to 5 or 6 cm (2.0 or 2.4 in). However, because of

tidal effects of the Moon, the length of a day increases at an average of 15 µs per

year, so any rotational change due to the earthquake will be lost quickly.

Similarly, the natural Chandler wobble of the Earth, which in some cases can be

up to 15 m (50 ft), will eventually offset the minor wobble produced by the

earthquake.

More spectacularly, there was 10 m (33 ft) movement laterally and 4–5

m (13–16 ft) vertically along the fault line. Early speculation was that some of

the smaller islands south-west of Sumatra, which is on the Burma Plate (the

southern regions are on the Sunda Plate), might have moved south-west by up to

36 m (120 ft), but more accurate data released more than a month after the

76

earthquake found the movement to be about 20 cm (8 in). Since movement was

vertical as well as lateral, some coastal areas may have been moved to below sea

level. The Andaman and Nicobar Islands appear to have shifted south-west by

around 1.25 m (4 ft 1 in) and to have sunk by 1 m (3 ft 3 in).

In February 2005, the Royal Navy vessel HMS Scott surveyed the

seabed around the earthquake zone, which varies in depth between 1,000 and

5,000 m (550 and 2,730 fathoms; 3,300 and 16,400 ft). The survey, conducted

using a high-resolution, multi-beam sonar system, revealed that the earthquake

had made a huge impact on the topography of the seabed. 1,500-metre-high

(5,000 ft) thrust ridges created by previous geologic activity along the fault had

collapsed, generating landslides several kilometers wide. One such landslide

consisted of a single block of rock some 100 m high and 2 km long (300 ft by

1.25 mi). The momentum of the water displaced by tectonic uplift had also

dragged massive slabs of rock, each weighing millions of tons, as far as 10 km

(6 mi) across the seabed. An oceanic trench several kilometres wide was

exposed in the earthquake zone.

The TOPEX/Poseidon and Jason-1 satellites happened to pass over the

tsunami as it was crossing the ocean. These satellites carry radars that measure

precisely the height of the water surface; anomalies of the order of 50 cm (20 in)

were measured. Measurements from these satellites may prove invaluable for

the understanding of the earthquake and tsunami. Unlike data from tide gauges

installed on shores, measurements obtained in the middle of the ocean can be

used for computing the parameters of the source earthquake without having to

compensate for the complex ways in which close proximity to the coast changes

the size and shape of a wave.

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Chapter III: Effects of Earthquake, Volcano & Tsunami

3.1 Effects of Earthquake:

The Researcher Propose that a general study of earthquakes includes:

consideration of the nature of ground faults, the propagation of shock waves

through the earth mass, the specific nature of recorded major quakes, etc.

However, the material presented here is focused mainly on the basic concepts of

designing the buildings capable to resist earthquake effects, which is a scope

of earthquake engineering, the branch of engineering devoted to mitigating

earthquake hazards. Earthquake engineering covers the investigation and

solution of the problems created by damaging earthquakes, and consequently the

work involved in the practical application of these solutions, i.e. in planning,

designing, constructing and managing earthquake-resistant structures and

facilities.

Characteristics of Earthquakes:

The Researcher Propose that a major earthquake is usually rather short in

duration, often lasting only a few seconds and seldom more than a minute or so.

In general, during a quake there are usually one or more major peaks of

magnitude of motion. These peaks represent the maximum effect of the quake.

Although the intensity of the quake is measured in terms of the energy

release at the location of the ground fault, the critical effect on the given

structure is determined by the ground movements at the location of the structure.

The effect of these movements is affected mostly by the distance of the structure

from the epicenter, but they are also influenced by the geological conditions

directly beneath the structure and by the nature of the entire earth mass between

the epicenter and the structure.

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Modern recording equipment and practices provide us with

representations of the ground movements at various locations, thus allowing us

to simulate the effects of major earthquakes. One of the most common

earthquake representations is acceleration of the ground in one horizontal

direction plotted as a function of elapsed time; a typical acceleration record of

an earthquake is shown on the figure below. For use in physical tests in

laboratories or in computer modeling, records of actual quakes may be "played

back" on structures in order to analyze their responses.

Although it may seem like a gruesome way to achieve it, we advance our

level of competency in design every time there is a severe earthquake that results

in some major structural damage to buildings. Engineering societies and other

groups routinely send investigating teams to the sites of major quakes to report on

the effects on buildings in the area. Of particular interest are the effects on

recently built structures, because these buildings are, in effect, full-scale tests of

the validity of our most recent design techniques. Each new edition of the

building codes reflects some of the results of this cumulative growth of

knowledge gained from the latest disasters.

General Effects of Earthquakes:

The Researcher Propose that the ground movements caused by

earthquakes can have several types of damaging effects. Some of the major

effects are:

• Ground shaking, i.e. back-and-forth motion of the ground, caused by the

passing waves of vibration through the ground;

• Soil failures, such as liquefaction and landslides, caused by shaking;

• Surface fault ruptures, such as cracks, vertical shifts, general settlement of an

area, landslides, etc.

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• Tidal waves (tsunamis), i.e. large waves on the surface of bodies of water that

can cause major damage to shoreline areas.

A dramatic illustration of several building collapses (entire buildings

tilted over) induced by soil failure (liquefaction) in the 1964 Niigata (Japan)

earthquake is shown in the figure below.

The effects of an earthquake include fire, loss of life‘s, tidal waves that

cause tsunami, avalanches, flooding, broken gas lines and destroy of roads and

bridges. Other effects include building damages and spilling of hazardous

chemicals.

The effect of an earth quake is dependent on its strength and magnitude.

An earth quake strong in both strength and magnitude leads to the destruction of

property, landslides and tsunamis if the area is close to a water body. Mild earth

quakes cause minimal damage like cracks on building walls and swaying of

buildings.

The effects of earthquakes include: avalanches, tidal waves (tsunamis),

fires, flooding, death, building damage, destruction of infrastructures, broken

gas lines and spills of hazardous chemicals. An earthquake is the consequence of

an abrupt release of energy in the Earth's crust that generates seismic waves.

The effects of earthquakes include: direct shaking of manmade structures

such as buildings and bridges, landslides and liquefaction due to the stress of

seismic waves and tsunamis off the coasts of affected regions. Tsunamis

typically have waves that reach up to 10 meters.

The effects of earthquakes include damage to buildings and in worst

cases the loss of human life. The effects of the rumbling produced by

earthquakes usually leads to the destruction of structures such as buildings,

bridges, and dams. They can also trigger landslides.

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Some of the most visible effects of an earthquake are damage to

buildings and roads and death. Other effects include broken gas lines, fires and

in some cases a tsunami.

The effects of earthquakes produce extreme damages. Some of the

massive earthquake cause massive damage. For instance loss of property and

lifestyles and deformed ground surfaces is also another damages with brings a

country that has been affected to a standstill in development. Exposure to deep

minerals and formation of new minerals is also an effect of earthquakes.

Direct Shaking Hazards and Human-Made Structures:

The Researcher Propose that most earthquake-related deaths are caused by

the collapse of structures and the construction practices play a tremendous role in

the death toll of an earthquake. In southern Italy in 1909 more than 100,000

people perished in an earthquake that struck the region. Almost half of the people

living in the region of Messina were killed due to the easily collapsible structures

that dominated the villages of the region. A larger earthquake that struck San

Francisco three years earlier had killed fewer people (about 700) because building

construction practices were different type (predominantly wood). Survival rates in

the San Francisco earthquake was about 98% that in the Messina earthquake was

between 33% and 45%)1. Building practices can make all the difference in

earthquakes, even a moderate rupture beneath a city with structures unprepared

for shaking can produce tens of thousands of casualties.

Although probably the most important, direct shaking effects are not the

only hazard associated with earthquakes, other effects such as landslides,

liquefaction, and tsunamis have also played important part in destruction

produced by earthquakes.

1 Zebrowski, 1997

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Geologic Effects on Shaking:

The Researcher Propose that when we discussed earthquake intensity we

discussed some of the basic factors that affect the amplitude and duration of

shaking produced by an earthquake (earthquake size, distance from fault, site and

regional geology, etc.) and as you are aware, the shaking caused by seismic waves

can cause damage buildings or cause buildings to collapse. The level of damage

done to a structure depends on the amplitude and the duration of shaking. The

amplitudes are largest close to large earthquakes and the duration generally

increases with the size of the earthquake (larger quakes shake longer because they

rupture larger areas). Regional geology can affect the level and duration of

shaking but more important are local site conditions. Although the process can be

complicated for strong shaking, generally shaking in soft sediments is larger and

longer than when compared with the shaking experienced at a "hard rock" site.

Effect of Earthquake on Built Environment:

The Researcher Propose that when an earthquake strikes it supplies a great

amount of sudden energy to buildings and structures. The only way this energy

can be absorbed by the building is by causing some damage. The damage could

be classified into two kind, structural members and non-structural. The non-

structural components are the window panes/ brick infill walls/ tiles/ false ceiling

etc. and this type of damage does not threaten the structural integrity of the

building, however, structural damage to columns, beams, shear walls and floor

slabs is also caused by the cracking of concrete and elongation/yielding of steel.

Effectively all energy absorbed is associated with some form of damage. When

the damage in the structural members crosses a threshold level which can also be

said to be the capacity of that building the building would collapse. Presently the

designers are aiming to absorb all of the seismic energy through controlled

yielding of steel and cracking of concrete so that the threshold danger level is not

exceeded. The aim is to use the full capacity of the structure so as to prevent a

total collapse. Even if the building does not collapse, the yielding of steel and

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cracks in concrete may cause the structure to be so badly damaged that the

building would be unusable and subsequently condemned.

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3.2 Effects of Volcano:

The Researcher Propose that volcanoes affect people in many ways, some

are good and some are not. Some of the bad ways are that houses, buildings,

roads, and fields can get covered with ash. As long as you can get the ash off

(especially if it is wet), your house may not collapse, but often the people leave

because of the ash and are not around to continually clean off their roofs. If the

ash fall is really heavy it can make it impossible to breathe.

Lava flows are almost always too slow to run over people, but they can

certainly run over houses, roads, and any other structures.

Pyroclastic flows are mixtures of hot gas and ash, and they travel very

quickly down the slopes of volcanoes. They are so hot and choking that if you are

caught in one it will kill you. They are also so fast (100-200 km/hour) that you

cannot out-run them. If a volcano that is known for producing pyroclastic flows is

looking like it may erupt soon, the best thing is for you to leave before it does.

Some of the good ways that volcanoes affect people include producing

spectacular scenery, and producing very rich soils for farming.

Gases:

The Researcher Propose that water vapor, the most common gas released

by volcanoes, causes few problems. Sulfur dioxide, carbon dioxide and hydrogen

are released in smaller amounts. Carbon monoxide, hydrogen sulfide, and

hydrogen fluoride are also released but typically less than 1 percent by volume.

Gases pose the greatest hazard close to the vent where concentrations are greatest.

Away from the vent the gases quickly become diluted by air. For most people

even a brief visit to a vent is not a health hazard. However, it can be dangerous for

people with respiratory problems.

The continuous eruption at Kilauea presents some new problems. Long

term exposure to volcanic fumes may aggravate existing respiratory problems. It

may also cause headaches and fatigue in regularly healthy people. The gases also

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limit visibility, especially on the leeward side of the island where they become

trapped by atmospheric conditions.

A deadly eruption:

The Researcher Propose that the 1815 explosive eruption of Tambora

volcano in Indonesia and the subsequent caldera collapse produced 9.5 cubic

miles (40 cubic kilometers) of ash. The eruption killed 10,000 people. An

additional 80,000 people died from crop loss and famine.

Aircraft:

The Researcher Propose that to put it mildly, ash is bad for jet aircraft

engines. Apparently the problem is much more severe for modern jet engines

which burn hotter than the older ones. Parts of these engines operate at

temperatures that are high enough to melt ash that is ingested. Essentially you end

up with tiny blobs of lava inside the engine. This is then forced back into other

parts where the temperatures are lower and the stuff solidifies. As you can

imagine this is pretty bad. One problem that I heard about is that pilots start losing

power and apply the throttle, causing the engine to be even hotter and melt more

ash. Added to this is the fact that ash is actually tiny particles of glass plus small

mineral shards–pretty abrasive stuff. You can imagine that dumping a whole

bunch of abrasive powder into a jet engine is not good for the engine. This has

been a pretty non-scientific explanation of the problem. I just found an article that

describes the problem a little more technically.

―The ash erodes sharp blades in the compressor, reducing its efficiency.

The ash melts in the combustion chamber to form molten glass. The ash then

solidifies on turbine blades, blocking air flow and causing the engine to stall.‖1

1 FAA Aviation Safety Journal, Vol. 2, No. 3.

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Major eruptions:

The Researcher Propose that the effect an eruption will have on a nearby

city could vary from none at all to catastrophic. For example, atmospheric

conditions might carry ash away from the city or topography might direct lahars

and pyroclastic flows to unpopulated areas. In contrast, under certain atmospheric,

eruption and/or topographic conditions, lahars, pyroclastic flows, and/or ash fall

could enter the city causing death and destruction.

This scenario brings up several interesting problems. How do you

evacuate a large population if there is little warning before the eruption? Where

do these people go? If an eruption is highly likely yet hasn‘t happened yet how

long can people be kept away from their homes and businesses?

I should point out that in most volcanic crises geologists‘ advice local civil

defense authorities. The civil defense authorities decide what to do concerning

evacuations, etc.

What happens to the towns around a volcano when it erupts depends on

many things. It depends of the size and type of eruption and the size and location

of the town. A few examples might help. The 1984 eruption of Mauna Loa in

Hawaii sent lava towards Hilo but the eruption stopped before the flows reached

the town. The 1973 eruption of Heimaey in Iceland buried much of the nearby

town of Heimaey under lava and cinder. The 1960 eruption of Kilauea in Hawaii

buried all of the nearby town of Kapoho under lava and cinder. In 1980, ash from

Mount St. Helens fell on many towns in Washington and Oregon. The 1902

eruption of Mount Pelee on the island of Martinique destroyed the town of Saint

Pierre with pyroclastic flows. In 1985, the town of Armero was partially buried by

lahars generated on Ruiz.1

There are many different types of volcanic eruptions and associated

activity: phreatic eruptions (steam-generated eruptions), explosive eruption of

1 Decker and Decker (1989)

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high-silica lava, effusive eruption of low-silica lava (e.g., basalt), pyroclastic

flows, lahars (debris flow) and carbon dioxide emission. All of these activities can

pose a hazard to humans. Earthquakes, hot springs, fumaroles, mud pots and

geysers often accompany volcanic activity.

The concentrations of different volcanic gases can vary considerably from

one volcano to the next. Water vapor is typically the most abundant volcanic gas,

followed by carbon dioxide and sulfur dioxide. Other principal volcanic gases

include hydrogen sulfide, hydrogen chloride, and hydrogen fluoride. A large

number of minor and trace gases are also found in volcanic emissions, for

example hydrogen, carbon monoxide, halocarbons, organic compounds, and

volatile metal chlorides.

Large, explosive volcanic eruptions inject water vapor (H2O), carbon

dioxide (CO2), sulfur dioxide (SO2), hydrogen chloride (HCl), hydrogen fluoride

(HF) and ash (pulverized rock and pumice) into the stratosphere to heights of 16–

32 kilometers (10–20 mi) above the Earth's surface. The most significant impacts

from these injections come from the conversion of sulfur dioxide to sulfuric acid

(H2SO4), which condenses rapidly in the stratosphere to form fine sulfate

aerosols. The aerosols increase the Earth's albedo—its reflection of radiation from

the Sun back into space – and thus cool the Earth's lower atmosphere or

troposphere; however, they also absorb heat radiated up from the Earth, thereby

warming the stratosphere. Several eruptions during the past century have caused a

decline in the average temperature at the Earth's surface of up to half a degree

(Fahrenheit scale) for periods of one to three years – sulfur dioxide from the

eruption of Huaynaputina probably caused the Russian famine of 1601–1603.

One proposed volcanic winter happened c. 70,000 years ago following the

super eruption of Lake Toba on Sumatra Island in Indonesia. According to the

Toba catastrophe theory to which some anthropologists and archeologists

subscribe, it had global consequences, killing most humans then alive and

creating a population bottleneck that affected the genetic inheritance of all

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humans today. The 1815 eruption of Mount Tambora created global climate

anomalies that became known as the "Year without a summer" because of the

effect on North American and European weather. Agricultural crops failed and

livestock died in much of the Northern Hemisphere, resulting in one of the worst

famines of the 19th century. The freezing winter of 1740–41, which led to

widespread famine in northern Europe, may also owe its origins to a volcanic

eruption.

It has been suggested that volcanic activity caused or contributed to the

End-Ordovician, Permian-Triassic, Late Devonian mass extinctions, and possibly

others. The massive eruptive event which formed the Siberian Traps, one of the

largest known volcanic events of the last 500 million years of Earth's geological

history, continued for a million years and is considered to be the likely cause of

the "Great Dying" about 250 million years ago, which is estimated to have killed

90% of species existing at the time.

The sulfate aerosols also promote complex chemical reactions on their

surfaces that alter chlorine and nitrogen chemical species in the stratosphere. This

effect, together with increased stratospheric chlorine levels from

chlorofluorocarbon pollution, generates chlorine monoxide (ClO), which destroys

ozone (O3). As the aerosols grow and coagulate, they settle down into the upper

troposphere where they serve as nuclei for cirrus clouds and further modify the

Earth's radiation balance. Most of the hydrogen chloride (HCl) and hydrogen

fluoride (HF) are dissolved in water droplets in the eruption cloud and quickly fall

to the ground as acid rain. The injected ash also falls rapidly from the

stratosphere; most of it is removed within several days to a few weeks. Finally,

explosive volcanic eruptions release the greenhouse gas carbon dioxide and thus

provide a deep source of carbon for biogeochemical cycles.

Gas emissions from volcanoes are a natural contributor to acid rain.

Volcanic activity releases about 130 to 230 teragrams (145 million to 255 million

short tons) of carbon dioxide each year. Volcanic eruptions may inject aerosols

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into the Earth's atmosphere. Large injections may cause visual effects such as

unusually colorful sunsets and affect global climate mainly by cooling it.

Volcanic eruptions also provide the benefit of adding nutrients to soil through the

weathering process of volcanic rocks. These fertile soils assist the growth of

plants and various crops. Volcanic eruptions can also create new islands, as the

magma cools and solidifies upon contact with the water.

Ash thrown into the air by eruptions can present a hazard to aircraft,

especially jet aircraft where the particles can be melted by the high operating

temperature; the melted particles then adhere to the turbine blades and alter their

shape, disrupting the operation of the turbine. Dangerous encounters in 1982 after

the eruption of Galunggung in Indonesia, and 1989 after the eruption of Mount

Redoubt in Alaska raised awareness of this phenomenon. Nine Volcanic Ash

Advisory Centers were established by the International Civil Aviation

Organization to monitor ash clouds and advise pilots accordingly. The 2010

eruptions of Eyjafjallajökull caused major disruptions to air travel in Europe.

The Earth's Moon has no large volcanoes and no current volcanic activity,

although recent evidence suggests it may still possess a partially molten core.

However, the Moon does have many volcanic features such as maria (the darker

patches seen on the moon), rilles and domes.

The planet Venus has a surface that is 90% basalt, indicating that

volcanism played a major role in shaping its surface. The planet may have had a

major global resurfacing event about 500 million years ago, from what scientists

can tell from the density of impact craters on the surface. Lava flows are

widespread and forms of volcanism not present on Earth occur as well. Changes

in the planet's atmosphere and observations of lightning have been attributed to

ongoing volcanic eruptions, although there is no confirmation of whether or not

Venus is still volcanically active. However, radar sounding by the Magellan probe

revealed evidence for comparatively recent volcanic activity at Venus's highest

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volcano Maat Mons, in the form of ash flows near the summit and on the northern

flank.

There are several extinct volcanoes on Mars, four of which are vast shield

volcanoes far bigger than any on Earth. They include Arsia Mons, Ascraeus

Mons, Hecates Tholus, Olympus Mons, and Pavonis Mons. These volcanoes have

been extinct for many millions of years, but the European Mars Express

spacecraft has found evidence that volcanic activity may have occurred on Mars

in the recent past as well.

Jupiter's moon Io is the most volcanically active object in the solar system

because of tidal interaction with Jupiter. It is covered with volcanoes that erupt

sulfur, sulfur dioxide and silicate rock, and as a result, Io is constantly being

resurfaced. Its lavas are the hottest known anywhere in the solar system, with

temperatures exceeding 1,800 K (1,500 °C). In February 2001, the largest

recorded volcanic eruptions in the solar system occurred on Io. Europa, the

smallest of Jupiter's Galilean moons, also appears to have an active volcanic

system, except that its volcanic activity is entirely in the form of water, which

freezes into ice on the frigid surface. This process is known as cry volcanism, and

is apparently most common on the moons of the outer planets of the solar system.

In 1989 the Voyager 2 spacecraft observed cry volcanoes (ice volcanoes)

on Triton, a moon of Neptune, and in 2005 the Cassini–Huygens probe

photographed fountains of frozen particles erupting from Enceladus, a moon of

Saturn. The ejecta may be composed of water, liquid nitrogen, dust, or methane

compounds. Cassini–Huygens also found evidence of a methane-spewing cry

volcano on the Saturnian moon Titan, which is believed to be a significant source

of the methane found in its atmosphere. It is theorized that cryovolcanism may

also be present on the Kuiper Belt Object Quaoar.

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A 2010 study of the exoplanet COROT-7b, which was detected by transit

in 2009, studied that tidal heating from the host star very close to the planet and

neighboring planets could generate intense volcanic activity similar to Io.

Traditional beliefs about volcanoes:

The Researcher Propose that many ancient accounts ascribe volcanic

eruptions to supernatural causes, such as the actions of gods or demigods. To the

ancient Greeks, volcanoes' capricious power could only be explained as acts of

the gods, while 16th/17th-century German astronomer Johannes Kepler believed

they were ducts for the Earth's tears. One early idea counter to this was proposed

by Jesuit Athanasius Kircher (1602–1680), who witnessed eruptions of Mount

Etna and Stromboli, then visited the crater of Vesuvius and published his view of

an Earth with a central fire connected to numerous others caused by the burning

of sulfur, bitumen and coal.

Various explanations were proposed for volcano behavior before the

modern understanding of the Earth's mantle structure as a semisolid material was

developed. For decades after awareness that compression and radioactive

materials may be heat sources, their contributions were specifically discounted.

Volcanic action was often attributed to chemical reactions and a thin layer of

molten rock near the surface.

A volcano is actually an opening or a fissure, in the Earth's crust, through

which lava or molten rocks, ash and toxic gases present below the surface of

Earth are discharged by a sudden, violent eruption. Sometimes, it can be a

mountain-like structure with a bowl-shaped depression at the top, through which

these substances are expelled. The term 'volcano' is derived from the name of the

Roman God of fire, Vulcan.

Volcanic structures are usually formed at places where the tectonic plates

are either converging or diverging. A stretching or thinning of the Earth's crust,

can also lead to the formation of volcanoes. They are often classified into three

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types, on the basis of their frequency of eruptions, i.e. active, dormant and extinct.

The active volcanoes are characterized by regular eruptions, while the dormant

volcanoes are those that erupted in the past, but are silent now. On the other hand,

an extinct volcano is the one that erupted in the remote past and is unlikely to

erupt again.

Effects on the Environment:

The Researcher Propose that it has been known for a long time that

volcanic eruptions affect the environment in various ways. Whether large or

small, eruptions do affect the environment for a period of time, mostly because of

the gases they spew out. Many gases, like sulfur dioxide, carbon dioxide, carbon

monoxide, chlorine (as HCl gas), fluorine (as HF gas), hydrogen, helium and

hydrogen sulfide (H2S) are released into the environment. Along with all these

comes out a huge amount of water vapor. Their effects on the environment

depend on many factors like the local climate pattern, the scale on which the

eruption has taken place, and the layer of the atmosphere to which the gases have

spread, etc.

Sulfur dioxide spreads to the top of the atmosphere where it reflects the

rays of the Sun, and thus leads to the cooling of the atmosphere. This has the

effect of bringing down the average global temperature, for a period of one or two

years. A famous example of this is the cooling of the surface temperature of the

Earth brought about after the eruption of Mount Pinatubo in Philippines.

Sulfur dioxide reacts with other gases and particles in the atmosphere to

form volcanic smog.

Sulfur dioxide also causes acid rain, air pollution, and depletion of the

ozone layer.

Carbon dioxide absorbs the Sun's rays, thereby increasing surface

temperature of the Earth.

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Carbon dioxide is a heavy gas and thus can get trapped in some low-lying

areas called depressions. People who breathe CO2-laden air of such an area can

succumb to death. CO2 can also accumulate in the soil.

Hydrogen chloride (HCl), owing to its extremely acidic nature, contributes

to acid rains after an eruption.

The volcanic ash released into the atmosphere after an eruption spreads to

hundreds of square miles. It blankets the atmosphere around the volcano, blocking

the rays of the Sun from reaching the ground. It has been theorized that a very

large volcano can cause a 'volcanic winter'.

Effects on Living Beings:

The Researcher Propose that volcanic eruptions affect plants and animals

in myriad ways. Moreover, these eruptions impact lives both directly (loss of life

and property), and indirectly (local environmental changes). Volcanic ash blows

out as minute particles. When it is inhaled, it can cause coughing and shortness of

breath. People suffering from asthma, bronchitis, and emphysema are especially

affected by it.

Coarser particles from pyroclastic flow can be lethal. When

inhaled, they cause death by choking the lungs and causing burns.

Exposure to ash also causes other symptoms like runny nose and

sore throat.

Extremely hot lava can swiftly kill plants and animals.

Due to the reduced visibility resulting from ash, accidents often

take place in the area around the eruption.

People living in vicinity of an eruption are at risk of injury and

even death by roof collapse. This is because ash particles

continually get deposited on the roofs of the dwellings. If the

weight increases beyond what a roof can endure, it buckles.

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Fine ash particles get in the eye and cause irritation, burning, and

itching. The cornea, which is the exposed part of the eye, suffers

abrasion and inflammation.

A volcanic eruption is a natural calamity which, besides causing loss of

human life and property, can cause considerable environmental changes. Though

we cannot prevent the occurrence of such eruptions, we can reduce their

devastating effects. Movement of magma, changes in the quantity and quality of

gases emitted by the volcanoes and small earthquakes can serve as signals of

volcanic eruptions. So, proper monitoring of these signals, ready disaster

management techniques, and creating awareness among the general public about

the hazards of volcanic eruptions can play an important role in minimizing the

losses that occurs during such a disaster.

Negative Effects:

The Researcher Propose that volcanoes affect people in many ways, some

are good, and some are not. Some of the bad ways are that houses, buildings,

roads, and fields can get covered with ash. As long as you can get the ash off

(especially if it is wet), your house may not collapse, but often the people leave

because of the ash and are not around to continually clean off their roofs. If the

ash fall is really heavy it can make it impossible to breathe.

Positive Effects:

The Researcher Propose that some of the good ways that volcanoes affect

people include producing spectacular scenery, and producing very rich soils for

farming. Volcanic eruptions create economic mineral deposits. All this often

generates tourism. These results can greatly boost a settlement's economy.

The main good effect that volcanoes have on the environment is to provide

nutrients to the surrounding soil. Volcanic ash often contains minerals that are

beneficial ot plants, and if it is very fine ash it is able to break down quickly and

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get mixed into the soil. Another benefit might be the fact that volcanic slopes are

often rather inaccessible, especially if they are steep. Thus they can provide

refuges for rare plants and animals from the ravages of humans and livestock.

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3.3 Effects of Tsunami:

The Researcher Propose that Tsunamis are some of the most devastating

natural disasters known to man. Think of a flood with its source being an ocean

and you can grasp a little of how much devastation tsunamis can create. For most

people who live in land the greatest threat is from overflowing rivers and creeks.

Normally extraordinarily heavy rainfall causes rivers and other waterways to

overflow. The excess water creates deadly currents and sweep away people,

causing them to drown. It also does a lot of damage in the initial surge and then

with standing water. A tsunami has all of these detrimental effects plus the added

destructive power crashing waves.

As you many know a tsunami is caused by a strong earthquake on the

ocean bed. The vibrations travel through the water traveling sometimes thousands

of kilometers. If you were on the water or deep sea diving in SCUBA gear you

would not notice much probably just rough waves or a momentarily strong

downward pull if you were underwater. However, a tsunami gains its true

destructive power as it approaches land. The water level becomes shallower

causing the waves caused by the earthquake to compress and combine. This is

what creates the massive and destructive waves that cause so much destruction.

Imagine over several tons worth of water either falling on you or surging

towards you. You would have a better chance at the Running of the Bulls. The

waves not only sweep people away, but can also destroy even well built

structures. The costs to human life can also be devastating. The deadliest tsunamis

in recorded history were the Christmas tsunamis of 2004 in the Indian Ocean. On

December 24, 2004, a massive 9.2 earthquake occurred of the island of Sumatra.

It created a deadly series of tsunamis that swept Indonesia, India, Madagascar,

and Ethiopia. The death toll was estimated to be in the neighborhood of 300,000

to 350,000. This was one of the greatest losses of life due to a major natural

catastrophe in modern history.

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The immediate destruction is only the beginning of the damage. After the

waters retreated there was the elevated risk of disease created by stagnant and

contaminated water. Since most tsunamis occur south of the Equator and In the

Pacific this only raises the risk of disease further.

There can also be more interesting effects that deal solely with scientific

curiosity. The Christmas tsunami was so powerful it actually sped up the rotation

of the Earth reducing the length of its sidereal day. The earthquake that spawned

it also caused the Earth to vibrate all over by as much as 1 cm.

The effects of a tsunami on a coastline can range from unnoticeable to

devastating. The effects of a tsunami depend on the characteristics of the seismic

event that generated the tsunami, the distance from its point of origin, its size

(magnitude) and, at last, the configuration of the bathymetry (that is the depth of

water in oceans) along the coast that the tsunami is approaching.

Small tsunamis, non-destructive and undetectable without specialized

equipment, happen almost every day as a result of minor earthquakes and other

events. They are very often too far away from land or they are too small to have

any effect when they hit the shore. When a small tsunami comes to the shoreline it

is often seen as a strong and fast-moving tide.

Tsunamis have long periods and can overcome obstacles such as gulfs,

bays and islands. These tsunamis make landfall usually in the form of suddenly

decreasing and then rapidly increasing water levels (not unlike a tidal bore) a

combination of several large waves or bore-type waves. Generally tsunamis

arrive, not as giant breaking waves, but as a forceful rapid increase in water levels

that result in violent flooding.

However, when tsunami waves become extremely large in height, they

savagely attack coastlines, causing devastating property damage and loss of life.

A small wave only 30 centimeters high in the deep ocean may grow into a

monster wave 30m high as it sweeps over the shore. The effects can be further

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amplified where a bay, harbour, or lagoon funnels the waves as they move inland.

Large tsunamis have been known to rise to over 100 feet!

Destruction:

The Researcher Propose that the amount of energy and water contained in

a huge tsunami can cause extreme destruction when it strikes land.

The initial wave of a huge tsunami is extremely tall; however, most

damage is not sustained by this wave. Most of the damage is caused by the huge

mass of water behind the initial wave front, as the height of the sea keeps rising

fast and floods powerfully into the coastal area. It is the power behind the waves,

the endless rushing water that causes devastation and loss of life. When the giant

breaking waves of a tsunami batter the shoreline, they can destroy everything in

their path.

Destruction is caused by two mechanisms: the smashing force of a wall of

water traveling at high speed, and the destructive power of a large volume of

water draining off the land and carrying all with it, even if the wave did not look

large.

Objects and buildings are destroyed by the sheer weight of the water, often

reduced to skeletal foundations and exposed bedrock. Large objects such as ships

and boulders can be carried several miles inland before the tsunami subsides.

Tsunami waves destroy boats, buildings, bridges, cars, trees, telephone

lines, power lines - and just about anything else in their way. Once the tsunami

waves have knocked down infrastructure on the shore they may continue to travel

for several miles inland, sweeping away more trees, buildings, cars and other man

made equipment. Small islands hit by a tsunami are left unrecognizable.

Especially along a high seismic area, known as the Ring of Fire, tsunamis

may have dramatic consequences as they hit less developed countries.

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The buildings infrastructures in these poorer nations are not well built and

cannot withstand the impact of the tsunami. Whole areas and towns are a picture

of destruction as the tsunami leaves at trail devastation and misery behind it.

Death:

The Researcher Propose that one of the biggest and worst effects of a

tsunami is the cost to human life because unfortunately escaping a tsunami is

nearly impossible. Hundreds and thousands of people are killed by tsunamis.

Since 1850 alone, tsunamis have been responsible for the loss of more than

430,000 lives. There is very little warning before a tsunamis hits land. As the

water rushes toward land, it leaves very little time to map an escape plan.

People living in coastal regions, towns and villages have no time to

escape. The violent force of the tsunami results in instant death, most commonly

by drowning. Buildings collapsing, electrocution, and explosions from gas,

damaged tanks and floating debris are another cause of death. The tsunami of

December 2004 that struck South East Asia and East Africa killed over 31,000

people in Sri Lanka only, leaving 23,000 injured.

Disease:

The Researcher Propose that Tsunami waves and the receding water are

very destructive to structures in the run-up zone. The areas close to the coast are

flooded with sea water, damaging the infrastructure such as sewage and fresh

water supplies for drinking.

Flooding and contamination of drinking water can cause disease to spread

in the tsunami hit areas. Illnesses such as malaria arise when water is stagnant and

contaminated. Under these conditions it is difficult for people to stay healthy and

for diseases to be treated, so infections and illnesses can spread very quickly,

causing more death.

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Environmental impacts:

The Researcher Propose that Tsunamis not only destroy human life, but

have a devastating effect on insects, animals, plants, and natural resources. A

tsunami changes the landscape. It uproots trees and plants and destroys animal

habitats such as nesting sites for birds. Land animals are killed by drowning and

sea animals are killed by pollution if dangerous chemicals are washed away into

the sea, thus poisoning the marine life.

The impact of a tsunami on the environment relates not only to the

landscape and animal life, but also to the man-made aspects of the environment.

Solid waste and disaster debris are the most critical environmental problem faced

by a tsunami-hit country.

Combined with the issue of waste is that of hazardous materials and toxic

substances that can be inadvertently mixed up with ordinary debris. These include

asbestos, oil fuel, and other industrial raw materials and chemicals. Rapid clean-

up of affected areas can result in inappropriate disposal methods, including air

burning and open dumping, leading to secondary impacts on the environment.

Contamination of soil and water is the second key environmental impact

of a tsunami. Salivation of water bodies such as rivers, wells, inland lakes, and

groundwater aquifers can occur in most cases. This also affects the soil fertility of

agricultural lands, due to salivation and debris contamination, which will affect

yields in the medium and long term. Sewage, septic tanks and toilets are damaged

contaminating the water supply.

Last but not least, there may be radiation resulting from damage to nuclear

plants, as it happened in Japan in March 2011. Since radiation exists for a long

time, it has the capacity to inflict damage upon anything exposed to it. Radiation

is most dangerous to animals and humans causing destruction as molecules lose

their electrons. The damage caused by radiation to the DNA structure determines

birth defects, cancers even death.

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Cost:

The Researcher Propose that massive costs hit communities and nations

when a tsunami happens. Victims and survivors of the tsunami need immediate

help from rescue teams.

Governments around the world may help with the cost of bringing aid to

devastated areas. National institutions, the United Nations, other international

organizations, community groups and NGOs, and a variety of other entities come

together to provide different kinds of aid and services. There might also be

appeals and donations from people who have seen pictures of the area in the

media.

Reconstruction and clean up after a tsunami is a huge cost problem.

Infrastructure must be replaced, unsafe buildings demolished and rubbish cleared.

Loss of income in the local economy and future losses from the destruction of

infrastructure will be a problem for some time to come.

The total financial cost of the tsunami could be millions or even billions of

dollars of damage to coastal structures and habitats. It is difficult to put an exact

figure on the monetary cost but the cost may represent an important share of a

nation‘s GDP.

Psychological Impacts of Tsunami:

The Researcher Propose that how would you feels if you lived through a

natural disaster? How would you feel afterwards? Could you imagine your life

being turned around, losing your house, losing your possessions, and losing loved

ones in a matter of minutes? Many people faced these questions after the 2004

Indian Ocean tsunami hit and changed their lives as they knew it. Natural

disasters can cause detrimental effects on the health and emotional well being on

those who are impacted by them. The fear that those who survive face after the

disaster can cause them to develop psychological problems. They may feel

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anxiety, stress, and panic when thinking about the disaster, reflecting back on it,

or even just encountering a new situation that is similar to the previous disaster.

Survivors of natural disasters, such as the 2004 tsunami, undergo psychological

distress that will harm their mental health and there are certain risks, symptoms,

emotional responses, and coping mechanisms that are associated with this

distress.

While the majority of survivors recover from disasters with no long lasting

effects on their psychological health, a fraction of the survivors will experience

long-term psychological distress. The level of distress is often dependent on both

pre-disaster and post-disaster factors. Pretrauma psychological symptoms are

often good indicators of post-disaster symptoms. Also, the extent to which the

disaster affected you plays a large role in post-disaster symptoms. Depending on

how much financial loss, material destruction, education levels, age, and the level

and quality of social support will lead to different amounts of distress after the

disaster. Impaired mental health is also due to the direct impact of the disaster,

such as physical injury, the loss of loved ones, and the perception of life threat. A

study was done on a number of tourists who were in Stockholm, one of the

hardest hit cities, to determine their psychological distress based on different

types of psychological exposure. The study was done fourteen months after the

tsunami and showed that the more severely exposed groups faced more

psychological distress. It showed that the perception of life threat alone was

associated with both general and posttraumatic distress. Also, the lower the

education levels, the higher the percentage of posttraumatic stress. The younger

age groups experienced more general psychological distress while females

experienced both types of stress more than males.

One type of psychological distress that occurs after natural disasters is

posttraumatic stress. Posttraumatic stress disorder is a severe anxiety disorder

that can develop after exposure to any event and results in psychological trauma.

Diagnostic symptoms for PTSD include re-experiencing the original trauma

through flashbacks or nightmares, avoidance of stimuli associated with the

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trauma, and increased arousal. Due to the major destruction of India, the loss of

life, and relocations, many people developed this disorder. A study was

conducted in a coastal fishing village in Tamil Nadu, India to determine the

prevalence and risk factors that are associated with it. A community-based

household survey was given to the adults in the village. The survey was given

two months after the disaster hit. The Harvard Trauma Questionnaire was used to

assess posttraumatic stress disorder. The prevalence of the disorder was 12.7

percent. Some of the most common symptoms those who were facing this

disorder experienced were reoccurring thoughts and sleep disturbances. Less

prevalent symptoms included irritability and emotional numbness. Out of those

who sought help from a psychiatrist, 48.9 percent were diagnosed with major

depressive disorder and 31.9 percent were diagnosed with posttraumatic stress

disorder. Some of the risk factors for developing PTSD after the tsunami

included those with no household incomes, women, those who experienced

personal injury, and those who lost a family member due to the disaster.

While most the studies are conducted on adults, the distress and

posttraumatic stress in children also need to be analyzed. About 23-30 percent of

children develop full symptoms of posttraumatic stress disorder in the first six

months after disasters. Developing PTSD increases their risk of other disorders

and the impairment of psychological functioning. One of the most critical factors

in their chance of developing PTSD is the personal perception of life threat. Other

factors include a cultural perspective on the disaster and family support. A study

was conducted one year after the tsunami to determine the prevalence of PTSD in

children. It was conducted in the Akkaraipettai village in India. The age of the

children involved in the study ranged from ten to sixteen years old and they were

all in middle school. The two tests used were the Impact of Events Scale (IES)

and the Children‘s Revised Impact of Events Scale (CRIES) to identify the

prevalence of PTSD. Also using the Pediatric Emotional Distress Scale (PEDS),

the results showed that the disaster caused emotional distress to the children even

a year after it occurred. 94.2 percent of males and all females scored high on

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anxiety withdrawal and scored equally high on fearfulness. Another study found

that 13 percent developed posttraumatic stress disorder while 48 percent reported

re-experiencing and arousal symptoms. It also found that the loss of a family

member is a major contributing factor of children developing emotional distress

and PTSD.

Children who are indirectly exposed to natural disasters will show

emotional responses to them. One way to cope with such disasters is through art

therapy. One study used sand play to visually see the emotional responses of a

group of immigrant and refugee preschoolers living in South Asia only two weeks

after the tsunami hit. Flooding is a dangerous disaster because it can occur

without any warning and is very destructive. Preschoolers typically demonstrate

regressive behaviors, such as clinging, thumb sucking, bedwetting, whimpering

and loss of appetite, frightened facial expressions, and night terrors. This study

examined how children relive trauma through play. Although they were

indirectly exposed to the disaster, their parent‘s reactions greatly influenced

theirs, but very few children are at risk of developing posttraumatic stress

disorder. Also, the media‘s portrayal of the event has a negative impact on the

children‘s emotional responses because they absorb the visual images and

information without cognitively processing it. One attempt to allow children to

cope with the disaster is sand play, in which they can master their feelings by

creating scenes in a sand tray using human characters, religious figures, animals,

and objects. In this experiment, 29 percent of the children represented the

tsunami. 9 percent directly represented it, with the tsunami itself, devastating

floods, and babies who ended up in trees and rooftops. 20 percent indirectly

represented the tsunami with sea monsters devouring people and animals and

other cars and houses hidden in the sand. Some of the verbal representations

included, ―This is a tsunami,‖ ―Everyone is dead,‖ and ―People died in the water.‖

The children were enthusiastic about their creations but the main negative

emotions were sadness, followed by anxiety. Sand play helps the children to

come to terms and understand the disaster.

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Adults also had very profound emotional responses to the tsunami. In a

village of Tamil Nadu, emotional responses were obtained by the survivors. They

varied based on their occupation, how the tsunami affected their daily lives, and if

they or someone they loved was injured or lost. One fisherman reported that the

worst of his losses was the loss of his trust over the all-providing mother sea.

Both men and women considered that the loss of their pride had more

psychological impact than anything else. Parents who lost children were

inconsolable in their anguish and widows felt widow ship symbolized their fall

from grace and loss of security. After the tsunami many people‘s attitudes

changed towards life. Many housewives felt that men were more fatalistic after

the disaster. Parents believed that the tragedy shattered their dreams about their

children‘s career. Also, their financial standings changed and many felt they

became more economical and now have to plan for their finances. Teenager‘s

attitudes also changed as some believed they now have to be more serious and

responsible rather than easygoing.

Survivors of natural disasters explore several coping methods to try to

resolve their psychological distress. A study was conducted in a coastal village

of Tamil Nadu to gain insight on the coping mechanisms used by the local

communities nine months after the tsunami. Participants were selected based on

their social roles and included fisherman, housewives, community leaders, and

members of the youth. The survivors valued their unique, individual, social and

spiritual coping strategies more than formal health services. They had a tendency

to collectivize their personal sorrow. They viewed themselves as an integral part

of a larger traumatized society and not as lonely sufferers. The village has

frequent social gatherings to remember the deceased. Those who lost loved ones

adopted a custom of planting and caring for coconut saplings to remember them.

They offered foods favored by their loved ones who died to the saplings. Many

children sacrificed school to help earn livelihoods for their families. Also, the

community expressed four themes in their spiritual coping strategies: requiems,

rituals, religious beliefs, and spiritual seeking. Grief and mourning were loud and

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publicly demonstrated. Requiems were held with traditional music and social

customs. They believed in the existence of an immortal soul that would re-

incarnate them into higher forms of life. Most people claimed that their religious

beliefs were the most important factor contributing to their survival. Therefore

their religious practices were strengthened by the tsunami. This study showed

that coping mechanisms are shaped by ethno-cultural variations.

The 2004 tsunami that hit the Indian Ocean had detrimental effects on the

psychological health on those who survived the disaster, and even those who

heard about it through the media. Anxiety, psychological distress, and even

posttraumatic stress disorder became prevalent in those who were affected. The

degree in which they were affected was dependent on many factors. Those who

were more severely emotional hurt were those who had lower education levels,

less financial support, less family and social support, women, youth, those who

were personally injured, or those who lost love ones because of the tsunami.

Many coping mechanisms are available for those who experience psychological

distress, including art therapy, religious beliefs, community gatherings, and

professional help.

Victims of tsunami events often suffer psychological problems which can

last for days, years or an entire lifetime. Survivors of the Sri Lankan tsunami of

December 2004 were found to have PTSD (post traumatic stress disorder) when

examined by the World Health Organization (WHO): 14% to 39% of these were

children, 40% of adolescents and 20% of mothers of these adolescents were found

to have PTSD 4 months after the tsunami.

Impact Assessment of Tsunami 2004: Tamil Nadu, India

The Researcher Propose that the 2004 Tsunami that struck South-east

Asian countries is a rarest of rare earth dynamics. The Wegener‘s theory of ‗Plate

Tectonics‘ proved significantly correct indicating earths re-adjustments would be

disastrous and cause calamity to humanity. Experts say the bungling of marine

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ecological system would have long term impact. The first environmental

assessment of a range of coastal ecosystems along the south coast of India were

initiated by various organizations, including the NGOs providing some

preliminary observations on the nature and scale of the tsunamis impact on their

biophysical character.

After Tsunami: The Physical Impacts, Tamil Nadu, India

1. As high as 30,000 hectares of Cauvery delta area has turned saline, making the

land unfit for cereal cropping. The area needs reclamation.

2. The winter crops on coastal area especially in districts of Nagapattinam,

Tiuvarur, Cuddalore, as 20,000 hectares were inundated.

3. Casurina saplings, groundnut and horticultural crops raised in areas at

Kodiyakarai in Cuddalore district have withered.

4. Having lost the standing crops, the crop loss estimate may even touch 5-7

crores of rupees.

5. The agricultural activities were halted at 123 coastal villages in Nagapattinam

district 53 villages at Cuddalore district. Farmers say, that, the cultivation could

not be taken up for a few years in view of salinity of soil.

6. In few districts, the Paddy fields in some areas were sand cast up to a height of

15cms.

7. The water in wells far away from the sea have also become saline.

8. The most significant change caused by is the ―cartographic changes; that is

entire Indian continent was dragged to east by 9mm.

9. The entire marine ecology along Tamilnadu has been shattered.

10. Though Nagapattinam and Tiruvarur districts were known for their natural

drainage system, the silted canals and tall bunds put up by aqua culture farms

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contributed to water clogging for several hours in some areas. The sea breeze

added to the farmer‘s woes. Though the coconut, and cashew grooves withstood

the onslaught.

11. The coastal fresh water bodies have become saline, due to slamming of ocean

waves over them.

12. The soil chemistry on the coastal & neighbouring areas has changed, from its

original nature.

13. The texture and the composition of beach sand has changed.

14. LTL, HTL (low tide level and hide tide level) of coast has been changed,

observably.

15. The extent of Marine fishing area has been reduced observably.

16. The Two esturine mouths of Adyar and Cooum rivers have been widened, the

sand bars at the mouth area were washed away, allowing free mix of water of sea

and river.

17. The width of the beach has been reduced, because the shoreline has been

brought forward few metres.

18. Many coastal tourist spots have lost their attraction and charm hence the

tourism income also has been reduced drastically. Income coss loss may be

estimated at 15 to 20 crores.

19. Over night, the word Tsunami had become the buzzword of entire Indian

humanity.

20. The economic slump caused by Tsunami in the sectors like agriculture and

industries has affected the normal economic life.

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Tsunami: Economic impacts

1. The fishing economy along the coast has been seriously endangered.

Thousands of fishermen were missing, lost their fishing equipment, like nets,

fishing boats, rowing rods etc.

2. The imports and exports of marine products like fish, prawns, coral reeds,

oysters, pearl fishing etc were jeopardized.

3. Heavy monetary and property loss was found at Chennai Harbour. The cargo

sheds of the Chennai Port have been devastated beyond repair.

4. The reconstruction and restructuring of what has been lost would impair the

ongoing projects of future extension or developmental programmers.

5. Recapitalizing the damaged industrial units is a daunting task.

Estimated Loss of Tsunami, India:

(Direct Costs)

Human loss - 13,000-15,000

Missing Population - >45,000

No. affected - 2,50,000

Homeless - 3.75 lakhs

Material Loss - 1.5 billion

House broken - 6.7 lakhs

Fishing boats - 45,000

Merchant ships - 796

Lenth of Railway lines - 12,000 kms

Loss to Chennai fort & Harbour - 50 crores

Bridges of Causeways – 57

Raw cargo - 1.2 lakh tons

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Natural forests - 200 sq .km

Mangrove Forests - 500 sq .km

Marine life - l lakh tons

Private Property - 2.3 Billions

Live stock loss - 11,683 cows + 10721 sheep + 9788 goats

Poultry loss - Rs. 2 millions

Fish production - 20.30 million tons

Fishing Nets - 5 crores worth

Fishing Motor – 1576

Crop Loss - 5 to 6 crores.

Tsunami - Virtual loss:

(Intangible loss)

Psychologically depressed people - >3 Lakh

Water phobia affected people & children - >1.2 Lakh

Parent less children - >7.5 thousand

Widows - 4.2 thousands

Widowers - 1.3 thousands

Mentally depressed and stressed people - 12,000

Emotional, anxiety, anguish, pathos - >1 lakh

affected people no. of alcoholics - 47,000

Drugs intake – Considerably increased

Juvenile Criminals - increased by 30%

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Tsunami - Public Infrastructure Damage:

The Researcher Propose that the total irrigation area damaged is estimated

approximately 28000ha in province (9.6% of the total irrigated). Damage to

irrigation systems and rice fields may cause huge loss of rice production per year.

Two to three years may be needed to bring normal productivity back. All flood

control and coastal structures near the coast of Kanyakumari were severely

damaged by the tsunami, including up to 271kilometres upstream many rivers in

Kanyakumari district had real hard hit. Similarly the tsunami damaged completely

many state and National highway.

The number and severity of destroyed public facilities was massive. Two

major ports in Chennai and Tuticorin are completely out of function. Damage to

government offices and hospitals hindered a coordinated response during the first

month of emergency relief.

Tsunami- Livelihoods:

The Researcher Propose that the livelihoods of hundreds of thousands of

people have been affected. Examples include: An estimated 42,000 hectares of

prawn/fish farms along the coast have been lost, diminishing investments and

opportunities for small – scale businesses. Land tenure is now uncertain for many

families who used to live in the coastal strip. Uncertainties regarding the future of

rice farming, coconut plantations fish farms and open sea fishing (due to damage

of fishery equipments). Lost assets, belonging and livelihood security

possibilities, especially along the coastal strip, all of which may result in higher

dependency on natural resources.

Tsunami – Disturbed Ecosystem and Ground Water:

The Researcher Propose that many natural ecosystems (mangroves, coral

reefs, near shore zones including fish farms, freshwater reservoirs and the coastal

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strip) have been heavily damaged, leaving them more vulnerable to possible

future events such as high tides.

Strategies and Solutions:

The Researcher Propose that establishing a ―global warning system‖ for

Tsunamis in Indian Ocean should be mad mandatory, to protect the humanity

from another killer‘s tsunami. Economic activities along the coast, including

tourism development should be regulated under a uniform National policy

Permanent houses, leaving a safety distance (500m) from sea shore should

be constructed. A forestation, is the only method through which, loss can be

minimize. The protection of natural forests along the coast, stringent forest

policies should be adopted.

Reduction of residential colonies along the sea coast would minimize the

human loss and banning of residential colonies within 200 meters. Advanced

technology should be adopted at seismic stations, meteorological stations,

especially oceanographic research centers. Technical coordination between

developed and developing countries may certainly improve the forecasting

situations.

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Chapter IV: Safety Precautions

4.1 Safety Precautions of earthquake:

The Researcher Propose that there is no effective warning system for

earthquakes, which makes preliminary precautions even more critical. At the

same time, knowing how to behave when a quake strikes and what to do after the

event is just as important to staying safe.

Before an Earthquake:

The Researcher Propose that there are many things families and

individuals can do to prepare for an earthquake, including the following:

• Learn how to survive during the ground motion. This is described in the "During

the Earthquake" section below. The earthquake safety tips there will prepare you

for the fast action needed - most earthquakes are over in seconds so knowing what

to do instinctively is very important.

• Teach all members of your family about earthquake safety. This includes: 1) the

actions you should take when an earthquake occurs, 2) the safe places in a room

such as under a strong desk, along interior walls, and 3) places to avoid such as

near windows, large mirrors, hanging objects, heavy furniture and fireplaces.

• Stock up on emergency supplies. These include: battery operated radio (and

extra batteries), flashlights (and extra batteries), first aid kit, bottled water, two

weeks food and medical supplies, blankets, cooking fuel, tools needed to turn off

your gas, water and electric utilities.

• Arrange your home for safety: Store heavy objects on lower shelves and store

breakable objects in cabinets with latched doors. Don't hang heavy mirrors or

pictures above where people frequently sit or sleep.

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• Anchor heavy appliances and furniture such as water heaters, refrigerators and

bookcases.

• Store flammable liquids away from potential ignition sources such as water

heaters, stoves and furnaces.

• Get Educated. Learn what to do during an earthquake (see below). Then you

will be ready for the fast action needed. Make sure that all members of your

family have this important education.

• Learn where the main turn-offs are for your water, gas and electricity. Know

how to turn them off and the location of any needed tools.

• Install latches on cupboard doors to prevent them from opening during a quake.

• Use non-skid shelf liners for kitchen and bathroom cupboards, medicine

cabinets, and closet shelves.

• Store heavy items or glassware in lower cabinets so they do not become

dangerous projectiles.

• Update home insurance policies to adequately cover building costs, possession

replacement, and injury deductibles.

• Secure large appliances such as refrigerators, water heaters, air conditioners, and

other bulky items with straps, bolts, and other stabilizing methods.

• Be sure both old and new buildings meet earthquake construction requirements.

• Do not put heavy artwork, mirrors, or shelves over beds.

• Firmly secure bookcases, artwork, mounted televisions and other objects to

withstand as much shaking as possible.

• Take clear photos of valuables as a record for insurance purposes.

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• Prepare an earthquake emergency kit with non-perishable food, bottled water,

copies of important documents (birth certificates, prescriptions, insurance papers,

etc.), flashlights, first aid materials, blankets, spare glasses, and other essential

items and store it where it will be easily accessible in case of a quake.

• Keep cell phones charged and replace emergency kit supplies as necessary to

keep them usable.

• Plan alternative commuting routes in case an earthquake damages roads.

• Set up a family meeting location in a safe area.

• Teach all family members basic first aid, how to behave during a quake, and

what to do after a quake.

• Be prepared to act. Know how to act so your response is automatic. Identify safe

places in your work area to ‗Drop, Cover and Hold On.‘ Know at least two ways

to exit the building safely after an earthquake.

• Stock up on emergency supplies. Keep the basics: flashlight, first-aid kit,

whistle, gloves, goggles, blankets and sturdy shoes. Coordinate supplies with your

work group or department. Plan as if food and water may not be available for

about 24 hours and

• Other supplies for up to 3 days. Arrange your work area for safety. Make sure

that bookcases, large file cabinets and artwork are anchored. Store heavy objects

on low shelves. Store breakable objects in cabinets with latches. Use normal work

order process to get furniture anchored.

During an Earthquake:

The Researcher Propose that Earthquake can last just a few seconds or as

long as several minutes, and knowing how to react during the quake can help

prevent injuries:

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• If you are indoors, stay there. Quickly move to a safe location in the room such

as under a strong desk, a strong table, or along an interior wall. The goal is to

protect yourself from falling objects and be located near the structural strong

points of the room. Avoid taking cover near windows, large mirrors, hanging

objects, heavy furniture, heavy appliances or fireplaces.

• If you are cooking, turn off the stove and take cover.

• If you are outdoors, move to an open area where falling objects are unlikely to

strike you. Move away from buildings, power lines and trees.

• If you are driving, slow down smoothly and stop on the side of the road. Avoid

stopping on or under bridges and overpasses, or under power lines, trees and large

signs. Stay in your car.

• Immediately seek a safe location such as in a doorway (if you live in an old,

adobe house that is not reinforced), beneath a table or desk, or along an interior

wall away from windows or hazardous objects.

• Cover the back of your head and your eyes to minimize injury from flying

debris.

• Do not take elevators during an earthquake.

• If cooking, turn off heating elements immediately.

• If outdoors, stay in open areas away from buildings, power lines, trees, and other

potential hazards.

• If driving, stop quickly but safely and stay in the vehicle. Do not stop near

power lines, bridges, overpasses, or other potentially dangerous locations.

• Stay calm and brace yourself to keep your balance, sitting if possible.

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• Remain calm as the quake occurs – others will respond to your actions. A cool

head can prevent panic. If you are indoors when the shaking occurs, stay there.

Move away from windows and unsecured tall furniture. Drop, cover and hold on

under a desk, a table or along an interior wall. Protect your head, neck and face.

Stay under cover until the shaking stops and debris settles.

• If you are outdoors, move to an open area away from falling hazards such as

trees,

• Power lines, and buildings. Drop to the ground and cover your head and neck.

After an Earthquake:

The Researcher Propose that quick thinking after an earthquake hits can

minimize immediate dangers. Proper earthquake safety precautions after a tremor

include the following:

• Check for injuries; attend to injuries if needed, help ensure the safety of people

around you.

• Check for damage. If your building is badly damaged you should leave it until it

has been inspected by a safety professional.

• If you smell or hear a gas leak, get everyone outside and open windows and

doors. If you can do it safely, turn off the gas at the meter. Report the leak to the

Gas Company and fire department. Do not use any electrical appliances because a

tiny spark could ignite the gas.

• If the power is out, unplug major appliances to prevent possible damage when

the power is turned back on. If you see sparks, frayed wires, or smell hot

insulation turn off electricity at the main fuse box or breaker. If you will have to

step in water to turn off the electricity you should call a professional to turn it off

for you.

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• Be prepared for aftershocks, which may be stronger than the initial jolt.

• Tend injuries immediately and summon emergency assistance if necessary.

• Check for structural damage, but do not enter a building that shows damage or

has visible cracks in the walls or foundation.

• Wear shoes at all times to avoid stepping on broken glass.

• Turn off gas, electricity, and water if damage is suspected or if advised to do so

by authorities.

• Be cautious opening cabinets, cupboards, and closets in case items may be

poised to fall.

• Keep phone lines clear for emergency use.

• Be patient: It may take hours or days to restore all services depending on the

severity of the quake.

• Remain calm and reassuring. Check yourself and other for injuries. Do not move

injured people unless they are in danger. Use your training to provide first aid, use

fire extinguishers, and clean up spills. In laboratories, safely shut down processes

when possible.

• Expect aftershocks.

• After large earthquakes, tremors and aftershocks can continue for days.

• Be ready to act without electricity or lights. Know how to move around your

work area and how to exit in the dark. Know how to access and use your

emergency supplies. Be aware of objects that have shifted during the quake.

• If you must leave a building, use extreme caution. Continually assess your

surroundings and be on the lookout for falling debris and other hazards. Take your

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keys, personal items and emergency supplies with you if safe to do so. Do not re-

enter damaged buildings until an all-clear is given.

• Use telephones only to report a life-threatening emergency. Cell and hard-line

phone systems will be jammed. Text messages take less band width and may go

through when voice calls can‘t be made.

Earthquake Safety Rules:

The Researcher Propose that suggested safety rules during and after the

earthquakes are as follows:

During the earthquake:

1. Do not panic, keep calm.

2. Extinguish all fires.

3. If the earthquake catches you indoors, stay indoors. Take cover under a sturdy

piece of furniture. Stay away from glass, or loose hanging objects.

4. If you are outside, move away from buildings, steep slopes and utility wires.

5. If you are in a crowded place, do not rush for cover or to doorways.

6. If you are in a moving vehicle, stop as quickly as safety permits, but stay in the

vehicle until the shaking stops.

7. If you are in a lift, get out of the lift as quickly as possible.

8. If you are in a tunnel, move out of the tunnel to the open as quickly as safety

permits.

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After the earthquake:

1. Check for casualties and seek assistance if needed.

2. If you suspect a gas leak, open windows and shut off the main valve. Leave the

building and report the gas leaks. Do not light a fire or use the telephone at the

site.

3. Turn off the main valve if water supply is damaged.

4. Do not use the telephone except to report an emergency or to obtain assistance.

5. Stay out of severely damaged buildings as aftershocks may cause them to

collapse. Report any building damage to the authorities.

6. As a precaution against tsunamis, stay away from shores, beaches and low-

lying coastal areas. If you are there, move inland or to higher grounds. The upper

floors of high, multi-storey, reinforced concrete building can provide safe refuge

if there is no time to quickly move inland or to higher grounds.

Safety Precautions as a homeowner or tenant:

• Check your home for earthquake hazards, and create a plan to secure items that

may be vulnerable to shaking

• Bolt down or provide other strong support for water heaters and other gas

appliances, since fire damage can result from broken gas lines and appliance

connections. Use flexible connections wherever possible.

• Place large or heavy objects on the lower shelves. Securely fasten shelves to

walls. Brace or anchor high or top-heavy objects.

• In new construction or alterations, follow building codes to minimize earthquake

hazards. Sites for construction should be selected and engineered to reduce the

hazards of damage from an earthquake.

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• Keep a 7-10 day supply of food and water. To maintain freshness it is important

to rotate this stock periodically.

Safety Precautions as a parent or head of family:

• Hold occasional home earthquake drills to provide help avoid injury and panic

during an earthquake.

• Create a family emergency communications plan *(500K download) and make

sure everyone knows what to do. An earthquake could occur when your family is

not together. Take a few minutes with your family to establish a plan for how and

when to reunite after an earthquake.

• Teach responsible members of your family how to turn off electricity, gas, and

water at the main switch and valves. If in doubt, check with your local utilities

offices for instructions.

Caution: Never shut off gas unless you suspect a gas leak or can smell gas. If the

gas is ever shut off, all pilot lights must be re-lit.

• Provide responsible members of your family basic first aid and C.P.R. training.

Call Red Cross Safety Services for information about training classes.

• Keep a flashlight and a battery-powered transistor radio in the home, ready for

use at all times. Keep fresh batteries with these items.

• Keep immunizations up-to-date for all family members.

• Conduct calm family discussions about earthquakes and other possible disasters.

Avoid frightening disaster stories, but talk frankly and rationally about the

possible consequences of catastrophic events.

• Keep a 7-10 day supply of food and water. To maintain freshness it is important

to rotate this stock periodically.

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The Earthquake Preparedness:

The Researcher Propose that but whether earthquake prediction is possible

or not, one has to learn to live with them if one insists on living in areas with

earthquake hazard. So, most effort of scientists and engineers is focused on

earthquake preparedness, from both engineering and sociological points of view.

To prepare facing earthquakes, we must know two basic characteristics of

earthquakes, namely Magnitude and Intensity. The former is a measure of the

amount of energy released by the earth during the earthquake. It is represented on

a numerical scale of Richter Magnitude using the natural logarithm of maximum

displacement experienced by the ground. An earthquake of Richter magnitude

around 5.0 releases as much energy as that discharged by the Hiroshima nuclear

bomb. As the magnitude goes up by 1.0 on the Richter scale, the energy release

increases by about 30 times.

On the other hand, the consequence of the above energy released by the

earth is the damage and destruction to natural and man-made facilities.

Understandably, the damage will vary depending on the proximity of the facility

to the region where the slip has taken place along the earthquake fault. The extent

of this damage is measured on another scale called the Modified Mercalli

Intensity scale. This scale is a qualitative one and represented on a Roman scale I

to XII. Shaking from about intensity IV is felt by all human beings. Shaking

intensities VIII and IX reflect heavy damage in buildings. When shaking of the

Earth reaches the upper end of XII on the Modified Mercalli intensity scale, the

surface of the Earth is severely distorted.

Based on the occurrence of earthquakes in the past in and around India,

the country is divided into five seismic zones, namely zones I, II, III, IV and IV,

where I is the least severe and V is the most severe. Based on this zoning, about

60% of India‘s land area is under moderate seismic threat or more, i.e., under

seismic zone III or above. In fact, the 1993 Killari earthquake in which over

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10,000 persons died, occurred in an area that was considered to be non-seismic,

i.e., in seismic zone I. After this, the seismic zone map has been revised to have

only four seismic zones; with zone I merged to zone II. Even now, amongst our

four mega-cities, Delhi is in seismic zone IV, while Bombay, Calcutta and

Madras are in seismic zone III. Despite this level of seismic hazard, little is being

done, particularly in these cities, to make the development akin to earthquake

shaking. The quality of both design engineering and construction is way behind

the expected seismic standards.

The common man concept of an earthquake-proof house is only heuristic.

If one attempt to make a house that will not incur any damage during a large

earthquake, it is very likely that another pyramid will be built, though not of the

Egyptian scale. Yes, it is very uneconomical to build houses, or any structure for

that matter, that don‘t incur any damage during strong earthquake shaking.

Therefore, some amount of damage is permitted in structures, the extent being

decided based on the performance demand on the damaged structures. Hence,

engineering effort is to balance the cost of the structure with the controlled-

damage in it during an earthquake. The very engineers who are already well

conversant with making structures for no earthquake conditions, can design such

structures, termed as earthquake-resistant structures, with a little additional

education.

Design of structures for earthquakes is different from that for any other

natural phenomenon, like wind and wave. An earthquake imposes displacement

on the structure, while winds and waves apply force on it. The displacement

imposed at the base of the structure during an earthquake causes inertia forces to

be generated in it, which are responsible for damage in the structure. As a

consequence of this, the mass of the structure being designed assumes

importance; the more the mass, the higher is the inertia force.

After a whole gamut of earthquake experiences collected during the 20th

century from across the world, today the earthquake engineering community

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believes that there are four virtues of an earthquake-resistant structure. These are:

(a) sufficient strength – capacity to resist earthquake forces, (b) adequate stiffness

– capacity to not deform too much, (c) large ductility – capacity to stay stable

even after a damaging earthquake, and (d) good configuration – features of

building size, shape and structural system that are not detrimental to favorable

seismic behavior. Engineers designing structures for winds and waves, tend to

mostly concentrate their attention on the first two aspects, namely strength and

stiffness. However, in earthquake design, the latter two virtues assume a more

important role. The following parallel helps in better remembering these four

virtues. In looking for a bride-groom for your daughter, you are looking at a

prospective son-in-law who (a) is rich, so that he can take care of the shopping

requirements of your daughter, (b) is educated, so that he can easily find another

job if the company he is working in winds up, (c) can bend-backwards, to the

rather abrupt changes in mood of you daughter, and (d) has no vices.

Earthquake Engineering Education in India:

The Researcher Propose that India has had five moderate earthquakes

(Richter Magnitudes ~6.0-6.4) since 1988 as reminders to improve the earthquake

preparedness of the country. And, historically, some of the great earthquakes

(Richter Magnitudes >8.0) have occurred in India and that too four in the last 115

years. The world seismic community has taken advantage of the experiences from

these events, but we in India have paid no heed to these reminders. Today, the

number of persons interested in improving the earthquake preparedness in the

country is effectively very small. Moreover, most of these persons are in the

academia. And, when members of the academia suggest steps for improving the

preparedness, they are unfortunately charged with working for their own cause as

they tend to be branded as benefactors of increased activities in this direction.

There are poor/no campaign of sensitizing the decision-makers and

Government on the need for earthquake preparedness. Moreover, in the past four

decades, the earthquake engineering and preparedness education has been

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primarily restricted to within the classrooms. The academia has failed in guiding

the country with the right inputs at the right times. Every time an earthquake took

place in the country, the situation was not capitalized on. Earthquake engineering

is taught as a specialization only at the University of Roorkee and as an elective

course at a few of the IITs. In fact, the subject has been so mystified that it is

unfortunately considered to be very different from the mainstream civil

engineering. Consequently, there is a serious shortage of trained civil engineering

manpower with background in earthquake-resistant constructions.

Even today most consulting engineers do not follow even the available

Indian Standard design provisions for making earthquake-resistant constructions,

even in projects being executed in the Delhi, which is in seismic zone IV. But,

over the last century, seismic engineering has evolved in countries like Japan,

New Zealand and USA, and is reasonably well documented. The Indian

professional community can learn from this vast experience available across the

world.

Indian earthquake problem cannot be overemphasized. More than about

60% of the land area is considered prone to shaking of intensity VII and above

(MMI scale). In fact, the entire Himalayan belt is considered prone to great

earthquakes of magnitude exceeding 8.0, and in a short span of about 50 years,

four such earthquakes have occurred: 1897 Assam (M8.7), 1905 Kangra (M8.6),

1934 Bihar-Nepal (M8.4), and 1950 Assam-Tibet (M8.7).

Earthquake engineering developments started rather early in India. For

instance, development of the first seismic zone map and of the earthquake

resistant features for masonry buildings took place in 1930‘s, and formal teaching

and research in earthquake engineering started in late 1950‘s. Despite an early

start, the seismic risk in the country has been increasing rapidly in the recent

years. Five moderate earthquakes in the last eleven years (1988 Bihar-Nepal:

M6.6, about 1,004 dead; 1991 Uttarkashi: M6.6, about 768 dead; 1993 Latur:

M6.4, about 8,000 dead; 1997 Jabalpur: M6.0, about 38 dead; and 1999 Chamoli:

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M6.5, about 100 dead) have clearly underlined the inadequate preparedness of the

country to face damaging earthquakes. The paper discusses the developments of

earthquake engineering in India during the last one hundred years, the current

status of earthquake risk reduction in India, strengths and weaknesses of Indian

model of earthquake engineering developments, and the future challenges.

Two important elements emerge which need urgent attention to improve

the earthquake safety scenario in the country: the institutional development

whereby the discipline of earthquake engineering is nurtured and developed at a

much larger number of locations, and involvement of professional engineers and

architects into the seismic agenda. Quality manpower in earthquake engineering is

clearly in short supply and a major effort needs to be made to strengthen the same.

With the above background, it may be pertinent to discuss some recent positive

developments:

1. In recent years, earthquake engineering activities have spread to other

institutions in the country and active earthquake engineering groups now exist at

IIT Kanpur and Mumbai. Also, some of the CSIR laboratories are now engaged in

earthquake engineering research and consultancy. In addition, Nuclear Power

Corporation and other organizations dealing with nuclear power plants now have

considerable capabilities in earthquake engineering as is the case with some of the

top consulting firms.

2. A few individual enthusiasts are now spearheading the efforts towards

earthquake safety in their own region. For instance, a few engineers and architects

in Darjeeling (zone IV) have been instrumental in incorporation of nominal a

seismic provisions in the building bye-laws for that region. Another local group

has been pushing the agenda of earthquake safety in Imphal (zone V) in north-east

India.

3. The highly successful continuing education programmers conducted by IIT

Kanpur at different locations in the country, at times with class size of about 100

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persons, have created considerable interest amongst professional engineers, and

clearly demonstrated that the professional engineers are willing to join the seismic

safety agenda if given the right tools.

4. The Indian Concrete Journal, a very old and respected journal with wide-spread

readership amongst the professional engineers, has brought out two exclusive

issues related to earthquake engineering (ICJ 1994, 1998). The recently published

Vulnerability Atlas of India (BMTPC, 1997) is expected to help contribute

significantly in sensitizing the administrators and engineers to the earthquake

problem.

5. Five damaging earthquakes in the last eleven years have made it easier to

initiate discussions in the country on earthquake issues. The enormous tragedy of

the Latur earthquake and the massive earthquake rehabilitation program thereafter

have contributed significantly to capacity building and awareness at least in and

around Maharashtra. After the recent Chamoli earthquake, there is now a

discussion on setting up of a Earthquake Risk Evaluation Centre for north India.

6. A National Information Centre for Earthquake Engineering is in the process of

being set up at IIT Kanpur with the objective to acquire and disseminate the

earthquake engineering materials. In a developing country such as India, basic

poverty issues like food, shelter, health, and education remain the highest priority

and natural disaster mitigation does not get the priority that it should. Amongst

the major challenges ahead is to sensitize the policy makers, the politicians and

the administrators to the issues of earthquake safety. With five damaging

earthquakes in the last eleven years, this is the right time to initiate a sustained

and proactive effort in this direction.

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4.2 Safety Precautions during volcanic eruptions:

The Researcher Propose that explosive volcanoes blast hot solid and

molten rock fragments and gases into the air. As a result, ashflows can occur on

all sides of a volcano and ash can fall hundreds of miles downwind. Dangerous

mudflows and floods can occur in valleys leading away from volcanoes. If you

live near a known volcano, active or dormant, be prepared to follow volcano

safety instructions from your local emergency officials.

Mudflows:

The Researcher Propose that Mudflows are powerful ―rivers‖ of mud that

can move 20 to 40 mph. hot ash or lava from a volcanic eruption can rapidly melt

snow and ice at the summit of a volcano. The melt water quickly mixes with

falling ash, with soil cover on lower slopes, and with debris in its path. This

turbulent mixture is dangerous in stream channels and can travel more than 50

miles away from a volcano. Intense rainfall can also erode fresh volcanic deposits

to form large mudflows. If you see the water level of a stream begin to rise,

quickly move to high ground. If a mudflow is approaching or passes a bridge, stay

away from the bridge.

Stay out of the area defined as a restricted zone by government officials.

Effects of a volcanic eruption can be experienced many miles from a volcano.

Mudflows and flash flooding, wild land fires, and even deadly hot ash flow can

reach you even if you cannot see the volcano during an eruption. Avoid river

valleys and low lying areas. Trying to watch an erupting volcano up close is a

deadly idea.

Evacuation:

The Researcher Propose that although it may seem safe to stay at home

and wait out a volcanic eruption, if you are in a hazardous zone, doing so could be

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very dangerous. Stay safe. Follow authorities‘ instructions and put your volcano

evacuation plan into action.

Prepare for a Volcano Emergency:

• Learn about your community warning systems and emergency plans.

• Be prepared for the hazards that can accompany volcanoes:

Mudflows and flash floods

Landslides and rock falls

Earthquakes

Ash fall and acid rain

Tsunamis

• Make evacuation plans. If you live in a known volcanic hazard area, plan a route

out and have a backup route in mind.

• Develop an emergency communication plan. In case family members are

separated from one another during a volcanic eruption (a real possibility during

the day when adults are at work and children are at school), have a plan for

getting back together. Ask an out-of-state relative or friend to serve as the ―family

contact,‖ because after a disaster, it‘s often easier to call long distance. Make sure

everyone knows the name, address, and phone number of the contact person.

Have disaster supplies on hand:

• Flashlight and extra batteries

• First aid kit and manual

• Emergency food and water

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• Non-electric can opener

• Essential medicines

• Dust masks and goggles for every member of the household

• Sturdy shoes

During a Volcanic Eruption:

• Follow the evacuation order issued by authorities.

• Avoid areas downwind and river valleys downstream of the volcano.

• Listen to a battery-operated radio or television for the latest emergency

information.

If caught indoors:

• Close all windows, doors, and dampers.

• Put all machinery inside a garage or barn.

• Bring animals and livestock into closed shelters.

If trapped outdoors:

• Seek shelter indoors.

• If caught in a rock fall, roll into a ball to protect your head.

• If caught near a stream, be aware of mudflows. Move up slope, especially if you

hear the roar of a mudflow.

Protect yourself during ash fall:

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• Wear long-sleeved shirts and long pants.

• Use goggles to protect your eyes.

• Use a dust mask or hold a damp cloth over your face to help breathing.

• Keep car or truck engines off.

If possible, stay away from volcanic ash fall areas.

When outside:

• Cover your mouth and nose. Volcanic ash can irritate your respiratory system.

• Wear goggles to protect your eyes.

• Keep skin covered to avoid irritation from contact with ash.

• Clear roofs of ash fall. Ash fall is very heavy and can cause buildings to

collapse. Exercise great caution when working on a roof.

• Avoid driving in heavy ash fall. Driving will stir up more ash that can clog

engines and stall vehicles.

• If you have a respiratory ailment, avoid contact with any amount of ash. Stay

indoors until local health officials advise it is safe to go outside.

• Remember to help your neighbors who may require special assistance —

infants, elderly people, and people with disabilities.

A volcanic eruption can be an awesome and destructive event. Here are

some tips on how to avoid danger and what to do if you're caught near an

eruption.

Safety Tips:

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• Stay away from active volcanoes.

• If you live near an active volcano, keep goggles and a mask in an emergency kit,

along with a flashlight and a working, battery-operated radio.

• Know your evacuation route. Keep gas in your car.

If a Volcano Erupts in Your Area:

• Evacuate only as recommended by authorities to stay clear of lava, mud flows,

and flying rocks and debris.

• Avoid river areas and low-lying regions.

• Before you leave the house, change into long-sleeved shirts and long pants and

use goggles or eyeglasses, not contacts. Wear an emergency mask or hold a damp

cloth over your face.

• If you are not evacuating, close windows and doors and block chimneys and

other vents, to prevent ash from coming into the house.

• Be aware that ash may put excess weight on your roof and need to be swept

away. Wear protection during cleanups.

• Ash can damage engines and metal parts, so avoid driving. If you must drive,

stay below 35 miles (56 kilometers) an hour.

Before a Volcano:

• Put goggles and disposable breathing masks for each family member in your

disaster supply kit.

• Stay away from active volcano sites.

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• If you live near a known volcano, active or dormant, learn about your

community warning systems and emergency plans, and be ready to evacuate at a

moment's notice.

• Have an emergency disaster plan for you and your family.

• Be prepared for the hazards that can accompany volcanoes:

• Mudflows and flash floods

• Landslides and rock falls

• Earthquakes

• Ash fall and acid rain

• Tsunamis

During a Volcano:

• Listen to a battery-operated radio or television for the latest emergency

information.

• Follow the evacuation order issued by authorities.

• Avoid areas downwind and river valleys downstream of the volcano.

• If caught indoors:

• Close all windows, doors, and dampers.

• Put all machinery inside a garage or barn.

• Bring animals and livestock into closed shelters.

• If trapped outdoors:

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• Seek shelter indoors.

• If caught in a rock fall, roll into a ball to protect your head.

• If caught near a stream, be aware of mudflows. Move up slope, especially if you

hear the roar of a mudflow.

• Protect yourself during ash fall:

• Wear long-sleeved shirts and long pants.

• Use goggles to protect your eyes.

• Use a dust mask or hold a damp cloth over your face to help breathing.

• Keep car or truck engines off.

• Remember: Stay out of the area defined as a restricted zone by government

officials. Effects of a volcanic eruption can be experienced many miles from a

volcano. Mudflows and flash flooding, wild land fires, and even deadly hot ash

flow can reach you even if you cannot see the volcano during an eruption. Avoid

river valleys and low lying areas. Trying to watch an erupting volcano up close is

a deadly idea.

After a Volcanic Eruption:

• If possible, stay away from volcanic ash fall areas.

• When outside: Cover your mouth and nose. Volcanic ash can irritate your

respiratory system.

• Wear goggles to protect your eyes.

• Keep skin covered to avoid irritation from contact with ash.

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• Clear roofs of ash fall. Ash fall is very heavy and can cause buildings to

collapse. Exercise great caution when working on a roof.

• Avoid driving in heavy ash fall. Driving will stir up more ash that can clog

engines and stall vehicles.

• If you have a respiratory ailment, avoid contact with any amount of ash. Stay

indoors until local health officials advise it is safe to go outside.

• Remember to help your neighbors who may require special assistance infants,

elderly people, and people with disabilities.

You can do many things to protect yourself and your family from the

dangers a volcanic eruption can cause. The best way to do protect yourself and

your family is to follow the advice of local officials. Local authorities will provide

you with information on how to prepare for a volcanic eruption, and if necessary,

on how to evacuate (leave the area) or take shelter where you are.

If a pyroclastic flow, or lava flow is headed toward you:

• Leave the area immediately. If you are warned to evacuate because an eruption

is imminent, evacuate.

• If you can drive rather than walk, use your vehicle to evacuate. When driving

keep doors and windows closed, drive across the path of danger if you can or

away from the danger if you cannot, and watch for unusual hazards in the road.

Protecting yourself during ash fall:

• Stay inside, if possible, with windows and doors closed.

• Wear long-sleeved shirts and long pants.

• Use goggles to protect your eyes. If ash is continually falling, you may not be

able to shelter indoors for more than a few hours, because the weight of the ash

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could collapse the roof of your building and block air intakes into the building.

Listen to authorities for advice on leaving the area when ash fall lasts more than a

few hours.

• Exposure to ash can harm your health, particularly the respiratory (breathing)

tract. To protect yourself while you are outdoors or while you are cleaning up ash

that has gotten indoors, a disposable particulate respirator (also known as an ―air

purifying respirator‖) may be considered. An N-95 respirator is the most common

type of disposable particulate respirator and can be purchased at businesses such

as hardware stores. It is important to follow directions for proper use of this

respirator. For more information, see NIOSH-Approved Disposable Particulate

Respirators (Filtering Face pieces). If you don‘t have a particulate respirator, you

can protect yourself by using a nuisance dust mask as a last resort, but you should

stay outdoors for only short periods while dust is falling. Nuisance dust masks can

provide comfort and relief from exposure to relatively non-hazardous

contaminants such as pollen, but they do not offer as much protection as a

particulate respirator. Cleanup or emergency workers may need a different type of

breathing protection based on their work activity. Note that disposable particulate

respirators do not filter toxic gases and vapors.

• Keep your car or truck engine switched off. Avoid driving in heavy ash fall.

Driving will stir up ash that can clog engines and stall vehicles. If you do have to

drive, keep the car windows up and do not operate the air conditioning system.

Operating the air conditioning system will bring in outside air and ash.

Hazards:

The Researcher Propose that high speed lava flow containing toxic gases

and 400 degrees + molten rock, which would be too fast for a person to out run.

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Volcanic eruption clouds, liable to disperse ash over a large area (1000 km +)

and affecting the local infrastructure in various ways such as:

• Aircraft accessibility, diversions and delays.

• Food supplies, crops and live stock.

• Dangerous driving conditions: poor visibility.

• Vehicle air filtration systems blocked causing overheating and mechanical

failure.

• Drainage systems blocked and potential for local flooding.

• Railway lines affected.

• Water supplies affected.

Health problems as a result of ash particles within the atmosphere such as:

• Increased risk of Asthma reaction.

• General respiratory and breathing problems.

• Potential for severe reaction with moisture within lungs causing a cementing

affect within the lungs.

• Local eye irritation.

Preventative measures and recommendations:

• Monitor weather conditions particularly wind direction (wind changes direction

with attitude).

• Have plans to evacuate up wind to a safe area under cover.

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• Have clear medical evacuation plans, which may be affected by aircraft and

vehicle accessibility.

• Where protective face masks and goggles.

• Make regular updates with the volcanic monitoring centre.

• Have sufficient water, food and medical equipment supplies, when travelling

and at base location (minimum 72hours).

• Once major eruption as been declared have plans in place to return to a safe

location and at a suitable distance.

Preparation for those living in a volcano area:

The Researcher Propose that protecting your family in the event of a

volcanic eruption can mean the difference between life and death. More likely, it

will help you protect your health and property from volcanic "ash", rocks that can

spread for many miles. However, knowing how to prepare for a volcanic eruption

can be confusing without the right information. Organizing a plan of attack is key

to proper preparation, and educating everyone in your family or household will

help to better ensure their safety and well being when disaster erupts.

Put together an emergency supply kit. This kit is something that anyone

living in a volcano zone should have prepared at all times. The kit should include

such items as a first aid kit, food and water supplies, a mask to protect against ash

such as one used when mowing lawns, a manual can opener, a flashlight with

extra batteries or preferably a crank model, any necessary medications, sturdy

shoes, goggles or other eye protection, and a battery-powered radio. Ensure that

everyone in your family knows where the emergency supplies that you prepared

are located.

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A flashlight, phone charger, and radio combined as one, that runs on both

solar power and hand cranking is the ideal item to have ready in your house for

any natural disaster event. Pack this if you have one.

Buy proper respiratory protection. Purchase an air purifying respirator,

also referred to as an N-95 disposable respirator. This can be bought at your local

hardware store.

Have the necessary communication devices ready. Use your radio or

television at home to listen for volcano updates or evacuation notices.

Be aware of what your local disaster sirens sound like. When a volcanic

eruption occurs, you'll need to listen for those to go off.

Set an emergency evacuation plan with your family. Review it in depth

with them, so that each person knows what to do in the event of an eruption, how

to find one another if you're apart, and how to contact neighbors and/or

emergency services if you cannot get away from the property using your own

transportation.

• If anyone has disabilities, these need to be taken account of in the plan.

• Include pets and livestock in the plan.

• Discuss with your family what you will do if there are warnings to evacuate and

any of you don't want to leave. Bear in mind that it is not fair to other family

members if some of you choose to stay behind in spite of evacuation warnings,

and precautions should always be taken to ensure that those family members who

want to leave can do so.

• Know how to switch off all utilities and ensure that every family member old

enough to be responsible for turning off utilities knows how to do so.

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• Talking to children about the possibility of a disaster and what to do in the event

is better than pretending it may never happen. If children are aware that

everything is planned should something go wrong, their fear and anxiety will be

reduced in the event of a disaster because they'll know how to respond.

Create an emergency kit specifically for your car. It should include maps,

tools, a first aid kit if you haven't already packed one with your other emergency

supplies, a fire extinguisher, flares, additional non-perishable food, booster cables,

sleeping bags and/or emergency blankets, and a flashlight.

At the time of an actual evacuation:

The Researcher Propose that listen for advice and instructions. Check your

pre-prepared emergency gear and have it ready to go.

Prepare the car or other vehicle. Check that you have a full tank of gas and

keep all vehicles under cover until ready to leave (ash can prevent the engines

from working).

Make transportation arrangements with other families or friends if you do

not have a vehicle of your own.

Attend to livestock and pets. In the event that your house and property are

directly impacted by the volcano, your animals will not be able to escape. Do

what you can within reason to ensure their safety.

Place your livestock in an enclosed area or make arrangements to transport

them as far offsite as possible.

Make transportation plans for your family pets. Be aware that most

emergency shelters will be unable to accommodate them. If keeping your pets

with you, you'll need to be sure that you have planned ahead for enough food and

water for them. Alternatively, leave messages on social networking sites such as

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Twitter asking for people who are available in the area who can board your pets

temporarily until the disaster is over. You are bound to get a lot of kind offers.

Evacuate as instructed:

The Researcher Propose that takes your prepared kit with you, and makes

sure that your car emergency kit is in the car. Turn off the electric, gas, heating

oil, and water in your home if time allows. It is recommended that you don't turn

off the gas unless you suspect a leak or you're instructed to do so, as it can be

weeks before a professional can get to you to turn it back on after a disaster event.

Disconnect the appliances in your home if time allows. Take the designated

evacuation routes, and prepare yourself for delays. Other routes may be blocked,

so you want to ensure that you are taking the route suggested by authorities.

Stay put if you are instructed by the authorities to do so:

The Researcher Propose that run extra water in the sinks, bathtubs, and

other containers as an emergency supply for cleaning (use as little as possible) or

purifying and drinking. You can also get emergency drinking water from a water

heater.

Don't use the toilet if there is no running water. It will make the house

smell terrible. Instead, construct if necessary and use an emergency makeshift

toilet as described in the article Prepare for a Hurricane.

Close and secure all of the windows and any doors that lead to the outside.

Make sure that your heater, air conditioner and all fans are turned off.

Make sure that your fireplace damper is closed.

Continue to listen to the TV or radio for announcements and news.

Place your family into a room on ground level that does not have windows in it.

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Preparing for ash fall:

The Researcher Propose that the most likely hazard during a volcanic

eruption is ash fall. Knowing how to deal with it is important whether you're

remaining in place or you're traveling.

Stay indoors. Close all windows and doors; some may need to be sealed

with tape or similar (damp towels work well). Stopper up any vents to outside if

possible. Avoid using anything that sucks in air from outside or changes

circulation patterns by heating or exhausting air, such as air conditioning or

dryers.

Bring all pets indoors. If you have livestock, bring them into sheds, barns,

or other shelters. Even the garage will do as a temporary shelter. Ensure that

livestock have enough food and water.

Fill your bath and other containers with water. This may become a very

important water source if ash impacts local water supplies. Protect sensitive

electronics until the ash fall has well and truly ceased; only uncover them when

the environment is totally ash-free.

Keep your car, trucks, and any machinery under cover. If you cannot park

your vehicles somewhere inside, cover them with a car cover or tarpaulin. Avoid

driving unless you have no choice. Protect all machinery from volcanic ash by

covering in tarpaulins.

If you can, disconnect drainpipes from rain gutters (eaves troughs) from

downspouts or drainpipes. Doing this can help to prevent your drains clogging.

Disconnect the rainwater supply channel to any rainwater tanks to protect your

stored water and cover up any gaps on the tank.

Wear protective gear if you need to move around outside. If you have

them, wear safety goggles to protect your eyes, and a respirator to protect your

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lungs, and cover the rest of your body, including your head and hands, as much as

possible. Improvise a shemagh (Arab wraparound headscarf) to keep grit off your

head and out of your eyes and lungs. Even swimming goggles and clothing can be

used to protect your eyes and breathing if that's all you have.

When entering a building after being outside under ash, remove your outer

layer of clothing. The ash is difficult to remove from anything it falls on. Remove

contact lenses if going outside and wear glasses instead. If the ash gets in behind

contact lenses, it can cut into your eye, causing corneal abrasions.

After the ash fall, stay indoors and follow the radio instructions. When you

do go outside, keep away from ash falls and build-up of ash and continue to wear

protective clothing.

Don't drive through ash fall. It will clog your car's engine severely and

cause serious abrasion damage to the car. Keep children, pets, and animals

indoors. If pets and animals have ash on their fur, hoofs, or paws, wash it away to

prevent them from ingesting it and give them plenty of water to drink.

Try to remove ash fall from your roof. It looks like snow, but it's heavy

like sand and abrasive to breathe. If the amount of ash fall is too heavy, your roof

is in danger of collapsing: four inches (100mm) can collapse weaker roofs.[16].

No need to get it all off; leaving a thin layer is fine and sweeping it off would

make a lot of dust. Moisten ash using a sprinkler or spray hose to dampen it

before cleaning. Make sure you're wearing a protective mask and clothing.

Don't fall off your roof! It will be difficult for rescuers to notice or reach

you after a volcano. Unless you have special equipment, don't even try it on a

sloped roof more than one story up, or over hard or dangerous surfaces. Check for

property damage. Make notes and take photographs so that you can make your

insurance claim.

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• If you must go outside during the ash fall, try to put something over your mouth

and wear a gas mask.

• Check on friends and neighbors. This is especially important if you know they

may need assistance, or have special needs.

• Ideally have a landline telephone in the room in which you will be holding up.

This can be used to let your emergency contact know to keep their phone line

available in case you need to let them know about any life-threatening problems

or issues.

• Only use the phone lines for emergency calls to avoid clogging the

communications systems.

• Report broken utility lines to authorities if you see any.

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4.3 Safety Precautions during Tsunami:

The Researcher Propose that Tsunamis are ocean waves produced by

earthquakes or underwater landslides. As the waves approach the coast, their

speed decreases and their height increases. Waves that are 10 to 20 feet high can

be very destructive. Tsunamis don‘t happen very often, but when they do they

cause many deaths and injuries. Always listen to the radio and television for the

latest information and instructions for your area.

A Tsunami is a natural disaster that has occurred frighteningly frequently

in various parts of the world in the preceding decade. This makes for a need for

everyone living in or near coastal areas to be completely aware of what exactly a

tsunami is and the kind of damage it can cause to lives and property. A tsunami is

a massive wave of ocean water that rushes towards the coast at a mind boggling

pace and with a huge height due to an earthquake on the sea bed. Such a wave can

be extremely powerful and reduce everything in its path to rubble. It is thus vital

to be aware of the safety tips and precautions that can be followed to remain safe

and secure during a tsunami and increase one‘s chances of surviving such an

ordeal.

1. The first step is to make an assessment of the kind of risk and danger you are

in. You should try to gain knowledge about whether the town or city you live in is

located in a high risk zone or a relatively danger free zone.

2. If your town falls in a high risk zone that is vulnerable to tsunamis, you should

always try to remain updated on the weather reports in the region. When an

earthquake occurs on the floor of the sea, there is usually a time gap before the

wave actually hits the coast. This time must be well utilized to escape or evacuate

to higher ground or safer areas. Government warnings must be adhered to and

taken seriously.

3. An action plan must be in place that all your family members must be aware of

in case you find yourself in the midst of a tsunami. There should be earmarked

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safety shelters that everyone must proceed to when such an event happens. In case

there is no such plan in place, there can be utter chaos and confusion with no one

really sure what to do next.

4. In case you are on a beach and observe the sea completely receding backwards

in a most unnatural way, you should rush away from the coast line and try to go as

far away from the area as possible. The waters receding significantly is a sure shot

sign of an oncoming tsunami. If a smaller wave has already hit the shoreline and

the waters have completely receded after that, a tsunami is definitely on the way.

The water is just gathering enough potential energy to hit the shore hard.

5. If you are visiting a coastal region for a vacation or holiday in a high risk area,

you must choose a hotel that has safety measures and evacuation plans in place to

deal with a tsunami. The building where the hotel has been built must be

according to safety guidelines with enough exits and safety shelters in place. You

must also check whether the staff is well trained to handle such emergencies.

6. If you are on a ferry or a ship out into the sea and have no time to rush away

from the coast line on the land when you hear a warning about a possible tsunami,

it is best to rush out into the sea as far from the coastline as possible as the water

will rush onto the land and this will leave you safe and secure in the relatively

calmer waters of the sea.

Tsunami Safety Rules:

The Researcher Propose that a strong earthquake felt in a low-lying

coastal area is a natural warning of possible, immediate danger. Keep calm and

quickly move to higher ground away from the coast.

All large earthquakes do not cause tsunamis, but many do. If the quake is

located near or directly under the ocean, the probability of a tsunami increases.

When you hear that an earthquake has occurred in the ocean or coastline regions,

prepare for a tsunami emergency.

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Tsunamis can occur at any time, day or night. They can travel up rivers

and streams that lead to the ocean.

A tsunami is not a single wave, but a series of waves. Stay out of danger

until an "All Clear" is issued by a competent authority.

Approaching tsunamis are sometimes heralded by noticeable rise or fall of

coastal waters. This is nature's tsunami warning and should be heeded.

Approaching large tsunamis are usually accompanied by a loud roar that

sounds like a train or aircraft. If a tsunami arrives at night when you can not see

the ocean, this is also nature's tsunami warning and should be heeded.

A small tsunami at one beach can be a giant a few miles away. Do not let

modest size of one make you lose respect for all.

Sooner or later, tsunamis visit every coastline in the Pacific. All tsunamis -

like hurricanes - are potentially dangerous even though they may not damage

every coastline they strike.

Never go down to the beach to watch for a tsunami!

Tsunamis can move faster than a person can run!

During a tsunami emergency, your local emergency management office,

police, fire and other emergency organizations will try to save your life. Give

them your fullest cooperation.

Homes and other buildings located in low lying coastal areas are not safe.

Do NOT stay in such buildings if there is a tsunami warning.

The upper floors of high, multi-story, reinforced concrete hotels can

provide refuge if there is no time to quickly move inland or to higher ground.

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If you are on a boat or ship and there is time, move your vessel to deeper

water (at least 100 fathoms). If it is the case that there is concurrent severe

weather, it may may safer to leave the boat at the pier and physically move to

higher ground.

Damaging wave activity and unpredictable currents can effect harbor

conditions for a period of time after the tsunami's initial impact. Be sure

conditions are safe before you return your boat or ship to the harbor.

Stay tuned to your local radio, marine radio, NOAA Weather Radio, or

television stations during a tsunami emergency - bulletins issued through your

local emergency management office and National Weather Service offices can

save your life.

Follow nature‘s warnings: If you are in a low-lying coastal area and feel a

strong earthquake, keep calm and quickly move to higher ground away from the

coast.

Approaching tsunamis are sometimes heralded by noticeable rise or fall of

coastal waters. They are also usually accompanied by a loud roar that sounds like

a train or aircraft. These environmental cues are a natural warning. Keep calm and

quickly move to higher ground away from the coast.

The upper floors of high, multi-story, reinforced concrete hotels can

provide refuge if there is no time to quickly move inland or to higher ground.

A tsunami is not a single wave, but a series of waves. Stay out of danger

until an "ALL CLEAR" is issued by a competent authority.

Tsunamis are not surfable! They are not V-shaped or curling waves. Most

frequently they come onshore as a rapidly-rising turbulent surge of water choked

with debris.

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If you are on a boat or ship and there is time, move your vessel to deeper

water (at least 100 fathoms). If severe weather is also occurring, it may be safer to

leave the boat at the pier and physically move to higher ground until the ―ALL

CLEAR‖ is issued.

During a tsunami emergency, your local emergency management office,

police, fire and other emergency organizations will try to save your life.

Stay tuned to your local radio, marine radio, NOAA Weather Radio, or

television stations during a tsunami emergency. Bulletins issued through your

local emergency management office and National Weather Service offices can

save your life

Precautions for those at risk of a Tsunami:

The Researcher Propose that if you live in a coastal area that is hit by an

earthquake, especially near the Pacific Ocean, the chances of a tsunami hitting

increase. Take these precautions immediately after an earthquake.

-Turn on your radio or TV to hear if there is a tsunami warning

-Move away from the shoreline and to higher ground

-Do not go to the beach, especially if you see a noticeable recession of water away

from the shoreline.

Protecting your home and property:

The Researcher Propose that if you live in an area of the world where

tsunamis could occur, there are a few precautions you can take to help prevent

damage to your home and property.

-Elevate your home if it's on the coast.

-Make a list of things to bring inside in case a tsunami hits.

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-Have your home inspected by an engineer to determine ways to divert water

away from the structure.

-Contact your insurance agent. Homeowners' policies don't cover tsunami

flooding. Inquire about the National Flood Insurance Program.

Tsunami tips for boaters:

The Researcher Propose that if you are on a boat when a tsunami is

possibly approaching, move to deeper waters. Upon returning to your boat after a

tsunami hits land, be cautious because wave conditions may be severe and strong

currents may exist for a period after the tsunami hits.

Family Disaster Plan:

The Researcher Propose that long before a natural disaster strikes, it is

wise to create a family disaster plan, especially for children. Make the following

decisions before the evacuation actually occurs:

1. Determine a place to meet outside your neighborhood.

2. Determine a second meeting place in case the first one is damaged or ruined.

3. Decide on another family member (apart from members of your household) to

call to check-in in case you are separated. Ideally, the contact should be someone

out-of-state.

4. Designate someone to take the disaster kit when they evacuate.

Before and During a Tsunami:

• Know your local community's suggested evacuation routes to safe areas, where

shelter can be provided while you await the "all clear".

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• Be prepared to survive on your own for at least three days. To do this, you

should prepare an emergency kit for your home and car, along with a portable

one.

• Consider taking a first aid course and learn survival skills.

• Tune to a radio station that serves your area and listen for instructions from

emergency officials. Follow these instructions and wait for the "all clear" before

returning to the coast.

• Stay away from the beach – do not go down to watch a tsunami come.

• Move inland to higher ground immediately and stay there.

• If there is a noticeable recession in the water away from the shoreline, this is

considered ―nature‘s tsunami warning‖ and you should move away immediately.

After a Tsunami:

• Stay away from flooded and damaged areas until officials say it is safe to go

back.

• Stay away from debris in the water – it could cause health and safety risks.

• Save yourself first, not your possessions.

• Help injured or trapped people – give first aid where appropriate.

• Do not move seriously injured persons unless they are in immediate danger or

further injury.

• Help a neighbor who may require special assistance, like elderly people or small

children or people with disabilities.

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• Stay out of the building if water remains around it – tsunami waters, like flood

waters, can cause buildings to sink and collapse.

• Check food supplies – any food that has come in contact with flood waters

should be thrown out because it may be contaminated.

What to do or not to do under risk of tsunami:

If you are in an area at risk from tsunamis:

• You should find out if your home, school, workplace, or other frequently visited

locations are in tsunami hazard areas.

• Know the height of your street above sea level and the distance of your street

from the coast or other high-risk waters.

• Evacuation orders may be based on these numbers. Also find out the height

above sea level and the distance from the coast of outbuildings that house

animals, as well as pastures or corrals.

• Plan evacuation routes from your home, school, workplace, or any other place

you could be where tsunamis present a risk.

• If possible, pick areas (30 meters) above sea level or go as far as 3 kilometers

inland, away from the coastline. If you cannot get this high or far, go as high or

far as you can. Every meter inland or upward may make a difference. You should

be able to reach your safe location on foot within 15 minutes. After a disaster,

roads may become impassable or blocked.

• Be prepared to evacuate by foot if necessary. Footpaths normally lead uphill and

inland, while many roads parallel coastlines. Follow posted tsunami evacuation

routes; these will lead to safety. Local emergency management officials can

advise you on the best route to safety and likely shelter locations.

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• If your children's school is in an identified inundation zone, find out what the

school evacuation plan is. Find out if the plan requires you to pick your children

up from school or from another location. Telephone lines during a tsunami watch

or warning may be overloaded and routes to and from schools may be jammed.

• Practice your evacuation routes. Familiarity may save your life. Be able to

follow your escape route at night and during inclement weather. Practicing your

plan makes the appropriate response more of a reaction, requiring less thinking

during an actual emergency situation.

• Use a Weather Radio or stay tuned to a local radio or television station to keep

informed of local watches and warnings.

• Talk to your insurance agent. Homeowners' policies may not cover flooding

from a tsunami. Ask about the Flood Insurance Program.

• Discuss tsunamis with your family. Everyone should know what to do in a

tsunami situation. Discussing tsunamis ahead of time will help reduce fear and

save precious time in an emergency. Review flood safety and preparedness

measures with your family.

If you are visiting an area at risk from tsunamis:

The Researcher Propose that check with the hotel, motel, or campground

operators for tsunami evacuation information and find out what the

warning system is for tsunamis. It is important to know designated escape routes

before a warning is issued.

Protect Your Property:

• You should avoid building or living in buildings within 200 meters of the high

tide coastline. These areas are more likely to experience damage from tsunamis,

strong winds, or coastal storms.

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• Make a list of items to bring inside in the event of a tsunami. A list will help you

remember anything that can be swept away by tsunami water.

• Elevate coastal homes. Most tsunami waves are less than 3 meters. Elevating

your house will help reduce damage to your property from most tsunamis.

• Take precautions to prevent flooding. Have an engineer check your home and

advise about ways to make it more resistant to tsunami water. There may be ways

to divert waves away from your property. Improperly built walls could make

your situation worse. Consult with a professional for advice.

• Ensure that any outbuildings, pastures, or corrals are protected in the same way

as your home. When installing or changing fence lines, consider placing them in

such a way that your animals are able to move to higher ground in the event of a

tsunami.

What to Do if You Feel a Strong Coastal Earthquake:

The Researcher Propose that if you feel an earthquake that lasts 20

seconds or longer when you are in a coastal area, you should:

• Drop, cover, and hold on. You should first protect yourself from the earthquake

damages.

• When the shaking stops Gather members of your household and move quickly to

higher ground away from the coast. A tsunami may be coming within minutes.

• Avoid downed power lines and stay away from buildings and bridges from

which Heavy objects might fall during an aftershock.

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If you are on land:

• Be aware of tsunami facts. This knowledge could save your life! Share this

knowledge with your relatives and friends. It could save their lives!

• If you are in school and you hear there is a tsunami warning, you should follow

the advice of teachers and other school personnel.

• If you are at home and hear there is a tsunami warning, you should make sure

your entire family is aware of the warning. Your family should evacuate your

house if you live in a tsunami evacuation zone. Move in an orderly, calm and safe

manner to the evacuation site or to any safe place outside your evacuation zone.

Follow the advice of local emergency and law enforcement authorities.

• If you are at the beach or near the ocean and you feel the earth shake, move

immediately to higher ground, and DO NOT wait for a tsunami warning to be

announced. Stay away from rivers and streams that lead to the ocean as you

would stay away from the beach and ocean if there is a tsunami. A regional

tsunami from a local earthquake could strike some areas before a tsunami warning

could be announced.

• Tsunamis generated in distant locations will generally give people enough time

to move to higher ground. For locally-generated tsunamis, where you might feel

the ground shake, you may only have a few minutes to move to higher ground.

• High, multi-story, reinforced concrete hotels are located in many low-lying

coastal areas. The upper floors of these hotels can provide a safe place to find

refuge should there be a tsunami warning and you cannot move quickly inland to

higher ground.

• Homes and small buildings located in low-lying coastal areas are not designed to

withstand tsunami impacts. Do not stay in these structures should there be a

tsunami warning.

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• Offshore reefs and shallow areas may help break the force of tsunami waves, but

large and dangerous wave can still be a threat to coastal residents in these areas.

• Staying away from all low-lying areas is the safest advice when there is a

tsunami warning.

If you are on a boat:

The Researcher Propose that since tsunami wave activity is imperceptible

in the open ocean, do not return to port if you are at sea and a tsunami warning

has been issued for your area. Tsunamis can cause rapid changes in water level

and unpredictable dangerous currents in harbors and ports.

The Researcher Propose that if there is time to move your boat or ship

from port to deep water (after a tsunami warning has been issued), you should

weigh the following considerations:

• Most large harbors and ports are under the control of a harbor authority and/or a

vessel traffic system. These authorities direct operations during periods of

increased readiness (should a tsunami be expected), including the forced

movement of vessels if deemed necessary. Keep in contact with the authorities

should a forced movement of vessel be directed.

• Smaller ports may not be under the control of a harbor authority. If you are

aware there is a tsunami warning and you have time to move your vessel to deep

water, then you may want to do so in an orderly manner, in consideration of other

vessels.

• Owners of small boats may find it safest to leave their boat at the pier and

physically move to higher ground, particularly in the event of a locally-generated

tsunami.

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• Concurrent severe weather conditions (rough seas outside of safe harbor) could

present a greater hazardous situation to small boats, so physically moving yourself

to higher ground may be the only option.

• Damaging wave activity and unpredictable currents can affect harbors for a

period of time following the initial tsunami impact on the coast. Contact the

harbor authority before returning to port making sure to verify that conditions in

the harbor are safe for navigation and berthing.

What to Do After a Tsunami:

• You should continue using a Weather Radio or staying tuned to a Coast Guard

Emergency frequency station or a local radio or television station for updated

Emergency information. The Tsunami may have damaged roads, bridges, or other

places that may be unsafe.

• Check yourself for injuries and get first aid if necessary before helping injured

or trapped persons.

• If someone needs to be rescued, call professionals with the right equipment to

help many people have been killed or injured trying to rescue others in flooded

areas.

• Help people who require special assistance Infants, elderly people, those without

transportation, large families who may need additional help in an emergency

situation, people with disabilities, and the people who care for them.

• Avoid disaster areas. Your presence might hamper rescue and other emergency

operations and put you at further risk from the residual effects of floods, such as

contaminated water, crumbled roads, landslides, mudflows, and other hazards.

• Use the telephone only for emergency calls. Telephone lines are frequently

overwhelmed in disaster situations. They need to be clear for emergency calls to

get through.

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• Stay out of a building if water remains around it. Tsunami water, like

floodwater, can undermine foundations, causing buildings to sink, floors to crack,

or walls to collapse.

• When re-entering buildings or homes, use extreme caution. Tsunami-driven

floodwater may have damaged buildings where you least expect it. Carefully

watch every step you take.

• Wear long pants, a long-sleeved shirt, and sturdy shoes. The most common

injury following a disaster is cut feet.

• Use battery-powered lanterns or flashlights when examining buildings. Battery-

powered lighting is the safest and easiest to use, and it does not present a fire

hazard for the user, occupants, or building. Do not use candle.

• Examine walls, floors, doors, staircases, and windows to make sure that the

building is not in danger of collapsing.

• Inspect foundations for cracks or other damage. Cracks and damage to a

foundation can render a building uninhabitable.

• Look for fire hazards. There may be broken or leaking gas lines, flooded

electrical circuits, or submerged furnaces or electrical appliances. Flammable or

explosive materials may have come from upstream. Fire is the most frequent

hazard following floods.

• Check for gas leaks. If you smell gas or hear a blowing or hissing noise, open a

window and get everyone outside quickly. Turn off the gas using the outside main

valve if you can, and call the gas company from a neighbor's home. If you turn off

the gas for any reason, it must be turned back on by a professional.

• Look for electrical system damage. If you see sparks or broken or frayed wires,

or if you smell burning insulation, turn off the electricity at the main fuse box or

circuit breaker. If you have to step in water to get to the fuse box or circuit

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breaker, call an electrician first for advice. Electrical equipment should be

checked and dried before being returned to service.

• Check for damage to sewage and water lines. If you suspect sewage lines are

damaged, avoid using the toilets and call a plumber. If water pipes are damaged,

contact the water company and avoid using water from the tap. You can obtain

safe water from undamaged water heaters or by melting ice cubes that were made

before the tsunami hit. Turn off the main water valve before draining water from

these sources. Use tap water only if local health officials advise it is safe.

• Watch out for wild animals especially poisonous snakes that may have come

into buildings with the water. Use a stick to poke through debris. Tsunami

floodwater flushes snakes and animals out of their homes.

• Watch for loose plaster, drywall, and ceilings that could fall.

• Take pictures of the damage both of the building and its contents, for insurance

claims. Open the windows and doors to help dry the building.

• Shovel mud before it solidifies.

• Check food supplies. Any food that has come in contact with floodwater may be

contaminated and should be thrown out.

• Expect aftershocks If the earthquake was very large (magnitude 8 to 9+ on the

Richter scale) and located nearby. Some aftershocks could be as large as

magnitude 7+ and capable of generating another tsunami. The number of

aftershocks will decrease over the course of several days, weeks, or months

depending on how large the main shock was.

• Watch your animals closely. Keep all your animals under your direct control.

Hazardous materials abound in flooded areas. Your pets may be able to escape

from your home or through a broken fence. Pets may become disoriented,

particularly because flooding usually affects scent markers that normally allow

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them to find their homes. The behavior of pets may change dramatically after any

disruption, becoming aggressive or defensive, so be aware of their well-being and

take measures to protect them from hazards, including displaced wild animals,

and to ensure the safety of other people and animals.

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Chapter V: Legal Framework and other provision

5.1 Earthquake Disaster mitigation:

The Researcher Propose that the word mitigation may be defined as the

reduction in severity of something. Earthquake disaster mitigation, therefore,

implies that such measures may be taken which help reduce severity of damage

caused by earthquake to life, property and environment. While ―earthquake

disaster mitigation‖ usually refers primarily to interventions to strengthen the built

environment, and ―earthquake protection‖ is now considered to include human,

social and administrative aspects of reducing earthquake effects, however,

―earthquake mitigation‖ being more widely used and understood expression, it is

used here as synonym to ―earthquake protection‖

It should, however, be noted that reduction of earthquake hazards through

prediction was considered to be the one of the effective measures, and much effort

was spent on prediction strategies. While earthquake prediction does not

guarantee safety and even if predicted correctly the damage to life and property

on such a large scale warrants the use of other aspects of mitigation.

Role and responsibilities of different professionals in earthquake

disaster mitigation process:

Non Professional:

Group Pre-Disaster Post-Disaster

Media 1. Promoting

awareness and

preparedness

programs for

general public.

2. Guiding

government

agencies in

identifying

1. Special news

bulletins and

programs related

to happenings.

2. Highlights of

mitigation

techniques.

3. Realistic

reporting and

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existing hurdles,

their possible

causes and

removal.

3. Critical reviews

on research

directions,

education and

course of actions.

highly

professional

journalism

Government

Organizations

(GO) and Agencies

1. National disaster

preparedness

plans.

2. Code and

specification

enforcement.

3. Building and

infra-structure

stock

management.

4. Collaboration with

research

organizations and

universities.

5. Budgeting and

fund raising for

protection.

1. Developing

contingency

plans for

immediate and

long-term relief. 2. Co-ordination

between

National and

International

relief agencies. 3. Removing

hurdles for

immediate and

emergency

handling of

issues.

NGO’s 1. Developing

relevant data bank

at local level.

2. Imparting

awareness and

conducting

workshops and

training programs.

3. Linkage with

other GO‘s and

NGO‘s.

Fire fight, controlling

leakage of gases,

epidemic diseases

control, provision of

food, water, medicine,

clothes, temporary

bridges, temporary

roads, temporary

shelters.

Civil Defense 1. Preparing and

training for post

disaster relief

operation.

2. Sharing training

with civil

administration.

Fire fight, controlling

leakage of gases,

epidemic diseases

control, provision of

food, water, medicine,

clothes, temporary

bridges, temporary

roads, temporary

shelters.

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Rescue Workers 1. Preparing for

response to

disaster.

2. Developing skills

to the best of

abilities.

3. Registering with

local NGO or GO

as trained rescue

worker.

Fire fight, controlling

leakage of gases,

epidemic diseases

control, provision of

food, water, medicine,

clothes, temporary

bridges, temporary

roads, temporary

shelters.

Professional:

Group Pre-Disaster Post-Disaster

Engineers 1. Developing

insight into

engineering aspect

of earthquake

resistant

structures.

2. Persuading clients

to protect.

3. Designing

earthquake

resistant

structures.

4. Seismic

evaluation of

building and its

components.

5. Improving

earthquake

resistance of

existing buildings

and infrastructure

facilities.

1. Classifying

damaged

structures.

2. Demolition

techniques for

structures in a

progressive

collapse mode.

3. Proposing

choice of repair

methods and

strengthening

techniques.

Urban and Regional

Planners

1. Micro-zoning and

vulnerability

mapping.

2. Population density

optimization.

3. Protection

strategies for

infrastructure

facilities and

Learning from disaster

and updating plans.

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transportation.

Medical Doctors and

Paramedics

1. Developing

national data on

medical resources.

2. Categorizing

nodes according

to resources.

3. Training allied

professionals for

preparedness and

formulation of

preparedness

module.

4. Linkage with

international

Organizations for relief.

1. Emergency

mobilization of

resources.

2. Filtering

affected people

according to

requirements

and injuries.

3. Epidemic

control

strategies.

Researchers and

Academicians

1. Strengthening

understanding of

regional

seismicity,

collecting and

analyzing data and

developing

modules for

mitigation.

2. Developing

guidelines for

codes for local

building materials

and construction

methodologies.

3. Updating and

transferring

knowledge

through mid-

career training

programs for

professionals.

4. Advising different

agencies for

developing

contingency plans.

1. Assessing extent

of damage.

2. Learning from

disaster and

reconsidering

research options.

3. Preparing post-

disaster

rehabilitation

plans and

imparting

updated

information.

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Non-engineered construction:

The Researcher Propose that non-engineered construction as opposed to

engineered construction may be defined as buildings constructed without state-of-

the-art application and which is merely based on experience of local masons, and

skilled and semi-skilled workers. Since scientific consideration is absent, such

construction lacks seismic load resistance. While such construction most of the

time is prevalent in rural areas of the developing world, therefore, non-engineered

construction is mostly referred to the construction in rural areas of developing

countries. In the opinion of the author, however, the terminology should be

extended to structures where state-of-the-art applications have deliberately or

undeliberately been omitted, abused, misapplied or suppressed, specially after the

experience of the 2001 Bhuj earthquake (Gujarat, India), and other major disasters

in Iran and Turkey etc. and more recently the lethal Tsunami in the Indian Ocean.

An example of the frequent recurrence of severe earthquakes in an area marked

by prevalent non-engineered construction was seen on 1st Feb. 1991 in Chitral,

Pakistan. The northern area of Pakistan stretching from Chitral to Gilgit was

shaken up by an earthquake of magnitude 6.8 on the Richter scale. Approximately

100 villages were affected where almost 2900 houses were destroyed and almost

14786 houses were severely damaged. Intervention through engineering aspects

of earthquake disaster mitigation helped in reducing the severity of damage.

Rural construction in most parts of the third world is marked by its large

dead weights, both for walls and for roofs. Such construction while may be good

enough for gravitational forces and for thermal insulation, have to pay a heavy toll

when it comes to the earthquake forces, as it generates high seismic forces which

increases with weight and the height at which they occur. As most of the materials

used do not possess the desired strength and ductility, the destruction leads to

fatalities. Recent earthquakes in Iran, Turkey, India and Northern areas of

Pakistan are a testimony to the vulnerability of such a construction.

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Current methods of construction for both types of rural construction in

India, however, is said to incorporate few if any features for seismic safety. While

elaborating the construction techniques in rural housing to improve resistance to

seismic forces, reported that materials used for rural housing in northern areas of

India consist primarily of stone, wood and mud plaster. These materials are

locally available while the manufactured building materials such as cement and

steel, which have to be transported from outside, over long distances, and, over

tortuous routes, become too expensive. The construction techniques presently

employed are quite adequate for gravity loads, but are poor for lateral forces. The

walls and the roofs are thick and heavy, thereby leading to generation of large

lateral forces even during moderate earthquake, to be resisted by structures

lacking seismic resistance.

While discussing the design and construction needs for rural structures,

emphasized that the prevalent methods of rural construction in India results in

houses and farm structures that are often primitive and afford little protection

from natural hazards. Because of poor construction methods and absence of

planning, the whole pattern of rural settlement in India is unsatisfactory. All

dwellings need frequent repairs because of crack formation and other damages.

Very few rural dwellings can resist earthquakes, floods or other natural disasters

and are usually built afresh by the villagers in the same traditional manner. This

often results in a dwelling that is structurally even more unsound than the one

destroyed.

Whatever has been discussed by renowned researchers in this area holds

true for the majority of the rural construction in the Indian subcontinent, Iran,

Turkey and probably in many other developed countries, pointing to a need of

identifying technological errors in these types of construction and suggesting

ways and means to rectify them. A concerted effort, therefore, is desired by

planners, architects and structural engineers to mitigate the hazards that these

structures pose during and after earthquake.

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Earthquake Disaster Management: India

The Researcher Propose that the Disaster Management Act, 2005 (DM

Act, 2005) lays down institutional and coordination mechanism for effective

disaster management (DM) at the national, state and district levels. the

Government of India (GOI) in recognition of the importance of disaster

management as a national priority had set up a High Powered committee (HPC) in

August 1999 and a National Committee on Disaster Management (DM) after

Gujarat earthquake for making recommendation on the preparation of DM plans

and for suggestion effective of mitigation mechanism. Recommendation of the

HPC laid the foundation for DM framework in India.

The National Disaster Management Authority (NDMA) was created under

the chairmanship of Hon‘ble Prime Minister of India as the apex body for DM in

India. Similarly, such authorities at the states levels are headed by the Chief

Ministers or Governors as the case may be. Also, the District Disaster

Management Authorities are headed by District collectors and co-chaired by the

elected representatives of the respective district. With a Purpose to tackle these

issues very seriously, a provision is made to make such highest government

authorities to head such departments. The Act Also mandates the creation of the

Nation Disaster Response Force (NDRF) for specialized response and the

National Institute of Disaster Management (NIDM) for institutional capacity

development. These bodies have been set up to facilities the paradigm shift from

the hitherto relief-centric approach to a more proactive, holistic and integrated

approach of strengthening disaster preparedness, mitigation and emergency

response.

India‘s high earthquake risk and vulnerability is evident from the fact that

about 59 percent of India‘s land area could face moderate to severe earthquakes.

During the period 1990 to 2006, more than 23,000 lives were lost due to 6 major

earthquakes in India, which also caused enormous damage to property and public

infrastructure. The occurrence of several devastating earthquakes in areas hitherto

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considered safe from earthquakes indicated that the built environment in the

country indicates that the built environment in the country is extremely fragile and

our ability to prepare ourselves and effectively respond to earthquakes is

inadequate. All these major earthquakes established that the causalities were

caused primarily due to the collapse of buildings.

According to the latest seismic zone map of India, about 59 percent of

India‘s land area is vulnerable to moderate or severe seismic hazard, i.e. prone to

shaking of MSK intensity VII and above. In the recent past, most Indian cities

have witnessed the phenomenal growth of multi-growth of multistoried buildings,

super malls, luxury apartments and social infrastructure as a part of the process of

development. The rapid expansion of the built environment in moderate or high

risk cities makes it imperative to incorporate seismic risk reduction strategies in

various aspects of urban planning and construction of new structures. During the

period 1990-2006, India has experienced 6 major earthquakes that have resulted

in over 23,000 deaths and caused enormous damage to property, assets and

infrastructure.

A continuous and integrated process of planning, organizing, coordinating

and implementing measures which are necessary or expedient for prevention of

danger or threat of any disaster, mitigation or reduction of risk of any disaster or

its severity or consequences, capacity building, preparedness to deal with any

disaster, prompt response to any threatening disaster situation or disaster,

assessing the severity or magnitude of effects of any disaster, evacuation, rescue

and relief, and rehabilitation and reconstruction.

The critical areas of concern for the management of earthquake in India

include the:

• Lack of awareness among various stakeholders about the seismic risk;

• Inadequate attention to structural mitigation measures in the engineering

education syllabus;

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• Inadequate monitoring and enforcement of earthquake-resistant building codes

and town planning bye-laws;

• Absence of systems of licensing of engineers and masons.

• Absence of earthquake-resistant features in no engineered construction in

suburban and rural areas;

• Lack of formal training among professionals in earthquake-resistant construction

practices; and

• Lack of adequate preparedness and response capacity among various

stakeholder groups.

Guideline for earthquake management:

The Researcher Propose that Central ministries and Departments and the

State Governments will prepare DM plans, which will have specific components

on earthquake management, based on these Guidelines. These plans will cover all

aspects of the entire DM cycle, be reviewed and updated at periodic intervals and

implemented through appropriate, well coordinated and time bound actions as laid

down in these Guidelines. As most development activities, especially in high

seismic risk areas, can enhance earthquake risk unless special efforts are made to

address these concerns, all these agencies will make special efforts to ensure the

incorporate of earthquake-resistant features in the design and construction of all

new buildings and structures.

169

These Guidelines rest on the following six pillars of seismic safety for

improving the effectiveness of earthquake management in India.

Earthquake resistant design and construction of new structures:

The Researcher Propose that in most earthquakes, the collapse of

structures like houses, schools, hospitals and public buildings results in the

widespread loss of lives and damage. Earthquake also destroys public

infrastructure like roads, dams and bridges, as well as public utilities like power

and water supply installations. Past earthquakes show that over 95% of the lives

lost were due to the collapse of buildings that were not earthquake-resistant.

Though there are buildings codes and other regulations which make it mandatory

that all structures in earthquake-prone areas in the country must be built in

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accordance with earthquake-resistant construction techniques, new constructions

often overlook strict compliance to such regulations and building codes.

Faculty members in engineering colleges, architecture colleges, Industrial

Training Institutes (ITIs) and polytechnics will also be provided adequate

exposure to earthquake resistance design and construction techniques, so that

students are made aware of earthquake-resistance design and construction. While

the implementation of these Guidelines in areas within seismic Zone III will be

initiated during Phase I, these efforts will be intensified in these during Phase II.

There are approximately 12 crore buildings in seismic Zones III, IV and

V. Most of these buildings are not earthquake-resistant and are potentially

vulnerable to collapse in the event of a high intensity earthquake. As it is not

practically feasible or financially viable to retrofit all the existing buildings, these

Guidelines recommend the structural safety audit and retrofitting of select critical

lifelines structures and high priority buildings. Such selection will be based on

considerations such as the degree of risk, the potential loss of life and the

estimated financial implications for each structure, especially in high-risk areas,

i.e. seismic Zones III, IV and V. While these Guidelines indicate an illustrative

list of such buildings and structures, the state government/SDMAs will

consultation with their SEMCs and Hazards Safety Cells (HSCs), review their

existing built environment, and prepare such lists.

India has suffered the effects of a number of earthquakes in the recent past

in which the poor seismic performance of the built environment emerged as a key

area of concern. A number of initiatives have been taken in India to address this

problem and these include, among others, revision and strengthening of the codes

of practice, drafting of development regulations and building bylaws to take

seismic safety into account, sensitization and awareness building in the

community, and capacity building efforts directed at various stakeholders in the

building delivery process. Architects, as initiators of projects, coordinate the team

of professionals responsible for the building-delivery process. Therefore, there is

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an urgent need to reach out directly to tomorrow‘s architects through sensitization

in seismic safety issues to better prepare them for their professional roles.

Earthquake- resistant architecture has fairly recently been included in the

academic curriculum of undergraduate colleges of architecture.

To supplement and strengthen this, a unique initiative was launched in

India in 2008 to directly reach the undergraduate students of architecture through

an Annual Workshop Series that is now in its sixth year. Through these

workshops, nearly three hundred undergraduate students of architecture have been

trained in concepts of the earthquake resistance of buildings. The objective of the

series is to sensitize students of architecture in earthquake-resistant design

practices through technical lectures followed by design studios in which they are

given hands-on guidance in earthquake-resistant design by working on an

architectural design project in the Time Sketch format that they are familiar with.

This paper presents a brief overview of this activity.

The earthquake risk of a community is a function of its location in a

known earthquake-hazard zone, its population, and the condition of its building

stock. The risk gets exacerbated in the presence of high population densities,

especially in urban areas and vulnerable physical built environments for which

poor performance causes casualties and losses in earthquakes. There is thus a real

need for the civil engineering and architecture professions to be equipped with the

capacity to incorporate earthquake resistance in the built environment. Clearly,

the earthquake hazard transforms into a disaster in a vulnerable built environment,

in which building and lifeline collapses contribute to loss of lives and huge

financial losses. Major factors that determine the satisfactory seismic performance

of the built environment are: architectural configuration, structural design,

nonstructural elements, and quality of construction.

Buildings perform poorly during earthquakes due to the absence of

inadequacy of earthquake-resistant design processes and features which should

have been incorporated in all the stages of conception, design, analysis, and

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construction. Architects occupy the apex position in project conceptualization,

planning, and implementation, coordinating various professionals from different

disciplines including, but not limited to civil engineering, electrical and

mechanical engineering, geotechnical, sanitary, and plumbing engineering, and

urban planning. Poor conceptual design and detailing of various elements by the

architect will seriously impair the ability of structural and construction engineers

to incorporate adequate earthquake resistance in a building.

Regulation and Enforcement:

The Researcher Propose that a periodic revision of the codes and standards

relating to earthquake-resistant construction will be undertaken by drafting groups

within a fixed time-frame of five years or even earlier on priority basis, in keeping

with international practices. Other than the BIS, there are a number of other

bodies that develop design codes and guidelines in the country, e.g. the Indian

Roads Congress (IRC), Ministry of Shipping, Road Transport and Highway

(MoSRTH), Research Designs and Standards Organization (RDSO), Ministry of

Railways (MOR), and the Atomic Energy Regulatory Board (AERB), Department

of Atomic Energy (DAE). Codes developed by these organizations will also be

updated and made consistent with the current state-of-the-art techniques on

earthquake-resistant design and construction. These agencies also have a number

of construction practices regulated through internal memos, the reviews of which

will also b undertaken at the earliest.

Design provisions are required on many topics that have been addressed

so far in the existing codes or guidelines in India. Such topics include:

• Seismic design of non-structural elements and components of buildings and

structures.

• Seismic design of reinforced masonry structures.

• Seismic evaluation and strengthening of structures.

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• Seismic design of buried and above ground pipelines.

• Seismic design and ductile detaining of steel structures.

• Seismic design and ductile detaining of bridge piers.

• Seismic design, construction and manufacture of facilities, structures and

components related to electrical power generation, transmission and distribution.

• Seismic design of tunnels.

Creation of Public awareness on Seismic safety and risk reduction:

The Researcher Propose that a comprehensive awareness campaign will be

developed and implemented on the safe practices to be followed before, during

and after an earthquake. This campaign will also emphasize the prevalent seismic

risk and vulnerability of the states as well as highlight the roles and

responsibilities of all communities and stakeholders in addressing this risk.

• A handbook on earthquake safety will be prepared for the general public

highlighting the safety of persons (i.e., indoors, outdoors, and driving), buildings

and structures and non-structural contents of buildings.

• A homeowner‘s seismic safety manual will be prepared Emphasizing

earthquake-resistant techniques for new buildings and for the seismic

strengthening and retrofitting of existing buildings.

• A manual on structural safety audit of infrastructure and lifeline buildings will

be prepared.

• Translations of the above documents into local and regional languages will be

undertaken for easy comprehension.

• Video films will be prepared for the general public to articulate the earthquake

risk, vulnerability and preparedness and mitigation measures.

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Capacity development:

The Researcher Propose that the developments of high-quality education

materials, textbooks, field training and the improvement of the quality of teaching

at all levels will be given due emphasis. Education and training programmes will

be designed, with greater attention on developing the capacity and skills of

trainers and trained teachers. Appropriately designed science and technology

courses will be introduced to orient all targets groups including school teachers

and health professionals in the subject. The central and state government will

encourage knowledge institutions to undertake research, teaching a training,

which will further contribute to improving earthquake education in India.

The management and control of the adverse consequences of future

earthquakes will require coordinated, prompt and effective response systems at

the district and the community levels. Many of the components of response

initiatives are the same for different types of disasters and systems need to be

developed considering the multi-hazard scenario of various regions in order to

optimally utilize available resources.

The approach to Management of Earthquakes in India, as spelt out by

these Guidelines, envisages the institutionalization of initiatives and activities

based on scientific strategies, covering pre-earthquake components of prevention,

mitigation and preparedness, as well as post-earthquake components of

emergency response, rehabilitation and recovery. The objectives of all activities

related to the management of earthquakes is to evolve a community that is

informed, resilient and prepared to face such disasters in the future, with a

minimal loss of lives and damage to property, assets and infrastructure.

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Supplementary Damping - A New Concept in Earthquake Resistant

Buildings:

The Researcher Propose that a major earthquake is the most extreme

condition that a building may be required to survive during its lifetime. Incase

buildings are unable to survive this natures might then the price to be paid can be

colossal in terms of loss to lives and property. To survive this nature‘s fury safely

and surely also poses the greatest challenge to the architects and structural

engineers. However the modern day computational power and the technological

advances in the field of seismic protection have made the solution once

considered un-surmountable a reality. Considerable testing both in the field and

the laboratory coupled with quality research work has helped increase our

understanding of how buildings behave and respond during earthquakes and other

intense motions. This has led to newer approaches and methodologies towards

designing safer structures.

The heightened seismic activity in and around the Indian sub-continent

and the recent quakes in Kashmir and the low intensity temblors in Delhi, Gujarat

and eastern India are a constant reminder that we are living in an active seismic

belt. Awareness levels are growing and people today are becoming increasingly

savvy about the seismic components of the buildings they live and work in. Also

over the years the expectations of consumers has increased manifold, today many

expect and demand that their building/s be designed to the highest possible

standards. A decade ago most were satisfied with and wanted to prevent a total

building collapse, today many are demanding buildings that are safe to stay and

work in immediately after an quake. Important public buildings like hospitals and

emergency command centers are being designed for full functionality even during

a major earthquake.

When an earthquake strikes it supplies a great amount of sudden energy to

buildings and structures. The only way this energy can be absorbed by the

building is by causing some damage. The damage could be classified into two

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kind, structural members and non-structural. The non-structural components are

the window panes/ brick infill walls/ tiles/ false ceiling etc. and this type of

damage does not threaten the structural integrity of the building, however,

structural damage to columns, beams, shear walls and floor slabs is also caused by

the cracking of concrete and elongation/yielding of steel. Effectively all energy

absorbed is associated with some form of damage. When the damage in the

structural members crosses a threshold level which can also be said to be the

capacity of that building the building would collapse. Presently the designers are

aiming to absorb all of the seismic energy through controlled yielding of steel and

cracking of concrete so that the threshold danger level is not exceeded. The aim is

to use the full capacity of the structure so as to prevent a total collapse. Even if the

building does not collapse, the yielding of steel and cracks in concrete may cause

the structure to be so badly damaged that the building would be unusable and

subsequently condemned.

Population explosion has made high-rises the order of the day as it is the

only logical solution and way of accommodating the growing population within

the boundaries of the cities. It is needless to emphasize that tall buildings are

prone to larger movements and damage than low rise structures during

earthquakes and as the number of people occupying a high-rise at any given time

is far greater so also the risk of collateral damage. Apart from ensuring structural

safety during earthquakes high-rises are giving the engineers another cause of

concern i.e. mitigation of wind induced vibrations that cause occupant discomfort.

Excessive floor accelerations which are caused by relatively frequent strong wind

motions can render a building unserviceable for reasons of occupant discomfort.

Humans can perceive accelerations greater than one hundredth of that of

acceleration due to gravity. This effect is more pronounced in tall slender

buildings and for the building to qualify for serviceability the dynamic response

of the structure to wind induced vibrations needs to be reduced. To overcome

these effects the common approach is that of increasing the stiffness of the lateral

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load resisting members. This has two major disadvantages which can lead to

further complications and occasionally degradation in building design:

(a) Increased structural costs due to additional steel and concrete for making the

building stiffer and

(b) Increased stiffness would imply that the building now would attract higher

seismic forces than before.

Thus the vulnerability of the building for seismic loading becomes higher

which is a cause of concern.

Reinforced Concrete Structures are considered to possess 5% inherent

damping whereas steel structures are believed to have 2% damping. However

actual site measurements have shown that intrinsic damping of buildings is far

more complicated and variable than the generic figures of 2 and 5%. Damping

reduces as height increases and also the damping levels greatly differ from one

building to another. For building up to 50 meters in height the measured intrinsic

damping was seen to vary from 1 to 5% whereas for very tall structures greater

than 200 meters in height the intrinsic damping was just 0.5 to 1%. What is of

greater concern is that this intrinsic damping cannot be accurately known or

calculated at the design stage. The only way to tell the correct damping is by

physical testing and measurements after the building is constructed. This

uncertainty in the damping levels can prove fatal under seismic conditions. To

prove the case in point if in actual the damping is 1%, where as the designer has

designed the building assuming 5% damping then the structure so designed will

not be able to perform to the expected standards in the event of an earthquake.

This emphasizes the thought process that the designers should assume a

conservative damping value while designing else it is almost certain that even

with computer aided analysis and design the buildings designed would be unsafe.

Additional engineered and accurate damping can be very easily added to

buildings by installing certain mechanical devices called dampers. Dampers can

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provide damping up to 25-30% of the critical, thereby ensuring that the building

will perform very well in seismic conditions as also strong winds in case of very

tall buildings. Dampers act as shock absorbers and energy dissipaters during any

type of motion and thus prevent the building from damage. By using dampers the

designer is able to overcome the uncertainties of low intrinsic damping and this

helps in predicting the dynamic response accurately. By adding additional

damping the stiffness and building mass can also be reduced thereby ensuring that

the building is now subjected to lower seismic forces. The advantages of

additional damping is reduced building sway thus preventing damage to structural

and nonstructural components, reduced design forces as much of the energy is

dissipated by the dampers and the uncertainty in the level of intrinsic damping is

overcome through engineered supplementary damping.

Supplementary damping is also the most efficient and cost effective way

to achieve energy dissipation in buildings. This would inadvertently mean

decreasing the energy dissipation demand on the structural components i.e.

beams/columns/slabs thereby increasing the survivability of the building

structure. Dampers are mechanical devices that look somewhat like huge shock

absorbers and their function is to absorb and dissipate the energy supplied by the

ground movement during an earthquake so that the building remains unharmed.

Whenever the building is in motion during an earthquake tremor or excessive

winds, dampers help in restricting the building from swaying excessively and

thereby preventing structural damage. The energy absorbed by dampers gets

converted into heat which is then dissipated harmlessly into the atmosphere.

Dampers thus work to absorb earthquake shocks ensuring that the structural

members i.e. beam and columns remain unharmed. There are four types of

dampers i.e. Viscoelastic, Friction, Metallic Yield and Fluid Viscous.

(a) Traditional Viscoelastic dampers are stacked plates separated by inert polymer

materials. They have proved to be problematic over a varying temperature range

and have not achieved much success in practical applications due to the somewhat

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undesirable added spring effect of these devices. There are no manufacturers that

manufacture purely Viscoelastic damper.

(b) Friction dampers consist of sliding steel plates and work on the principal that

when two metal surfaces slide, friction heat is produced and energy gets

dissipated. These types of dampers are susceptible to corrosion and cold welding

which has a direct effect on the yielding threshold. There are also some associated

maintenance problems.

(c) Metallic dampers consist of multiple steel plates which yield when a threshold

force is reached. In other words these dampers become active only after a trigger

force is crossed. As the metal yields, it dissipates energy. These dampers are

required to be replaced after every seismic event. Over a period of time they have

also not been able to catch the momentum as the technology in the other damper

field has fast progressed.

(d) Fluid viscous dampers have existed for a long time and were developed and

used in the aerospace industry. After the end of the cold war era the US

government decided to make this technology available for civilian applications

and the seismic dampers are as a direct result of that. Fluid viscous dampers are

fluid filled metal cylinders with pistons and work like shock absorbers. They have

proved to be the most superior of the lot both for seismic and wind applications.

One of these biggest advantages is that they can be modeled to great accuracy and

therefore the response of structures using them can be accurately studied. They

absorb energy at all frequency ranges of the earthquake and also do not need to be

replaced after an earthquake. Generally the life of the fluid viscous damper will be

as long as the life of the structure it is protecting. They also have a great

flexibility in design and can be configured to protect against an earthquake of any

magnitude. They can be installed both on new and existing structures.

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5.2 Disaster risk governance in volcanic areas:

The Researcher Propose that a broad range of measures have been under

taken at different scales of governance to manage the risks associated with

environmental hazards in an attempt to strengthen the resilience of social,

physical and coupled systems. These activities, carried out by diverse sets of

actors, are shaped by complex institutional configurations that vary across socio-

political contexts. The types of measures adopted to manage risk and the

appropriateness of these measures have been the subject of intense debate in

disaster and disaster risk studies, as well as in international, intergovernmental

and NGO forums, but the institutional arrangements governing these choices have

received considerably less scrutiny. This absence is particularly noticeable in the

literature on volcanic disasters and disaster risks, where the focus has traditionally

been on the individual and collective actions of stakeholders living in close

proximity to the hazard and less on the prevailing governance regimes.

Three characteristics of disaster risk governance regimes are discussed and

provide the basis for further analysis of risk management and development

processes in volcanic areas: i) formal and informal institutional relationships; ii)

actors and networks; and iii) central-local governance arrangements. There are

obvious overlaps between these governance categories; for example, networks can

be both formal and informal, stretch across governance scales or be localised.

However, by analysing decision-making with respect to these analytical

categories, one can begin to comprehend the types of influences on collective

action decisions to manage risk across socio-political, temporal and hazard

contexts.

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The STREVA Approach: 1

The Researcher Propose that STREVA is a four-year UK Research

Council funded interdisciplinary project that aims to reduce the risks associated

with volcanic activity and hence the impact of volcanic disasters on people and

assets in the Caribbean and Latin America. It binds physical and social scientists,

local partners and policy-makers in understanding how risks interact and change

over time in volcanic areas, shaping disaster resilience. Part of the STREVA

project involves a retrospective or ‗forensic analysis‘2 of four well studied

volcanoes with recent eruptive histories: Soufrière Hills, Montserrat; Tungurahua,

Ecuador; Galeras, Colombia and Soufrière St Vincent, St Vincent and the

Grenadines.

By reconstructing and evaluating the conditions and causes involved in

particular destructive events at these volcanoes, as well as the collective

responses, STREVA aims to develop an understanding of the processes

contributing to and key components of resilience. It also seeks to produce a theory

of change that explains ‗the causal links that tie programme inputs to expected

programme outputs, or a plausible and sensible model of how a programme is

supposed to work‘2. Based on the indicators and theory of change generated

during the forensic process, STREVA will then assess resilience and the capacity

to manage the risks associated with future eruptions at two volcanoes with no

recent eruptive history: Cotacachi, Ecuador; and Cerro Machín, Colombia.

Potential volcanic disaster scenarios will be developed for each of these trial

volcano‘s, in partnership with local authorities, with the intention of promoting

learning and risk reduction without the need for a disaster to have occurred to

initiate these improvements.

STREVA is concerned with the role of governance systems and

institutional capacity in disaster resilience. This paper provides a conceptual basis

for understanding the links between the resilience of communities living close to

1 STREVA :- Strengthening Resilience in Volcanic Areas

2 Weiss, 1998: 55

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volcanoes and the governance systems that surround them. This disaster risk

governance framework will be tested and refined through its application in the

analysis of the governance systems contiguous with the four well-studied volcanic

systems. If it provides a useful categorisation of these regimes and the kind of

policies produced as a result to address disaster risk, it will then be used to guide

primary data collection and analysis at the trial volcanoes.

Governance and volcanoes:

The Researcher Propose that Volcano poses a specific set of governance

challenges because of their distinctive nature. Volcanic eruptions contribute only

a small percentage to total disaster impacts in terms of loss of life, the number of

people affected an economic damage; nevertheless, they present significant risks

to populations, livelihoods and infrastructure located nearby. This level of

exposure is increasing, driven by population growth and migration to large urban

centers such as Mexico City, Tokyo, Yogyakarta and Manila, located in volcanic

areas. Volcanoes also offer a number of benefits to those living on their slopes,

such as fertile soils for agriculture and tourism incomes; and some, such as

Merapi in Indonesia, are considered sacred by local people1. These factors do in

fact explain why people are there and what they are doing. Hence, although

resettlement programmes can reduce the level of exposure effectively, they may

be ethically and politically undesirable and have negative consequences for

livelihoods and the family economy.

High levels of uncertainty surrounding the volcanic hazards themselves

also create governance challenges. Eruptions and the associated risks are

notoriously hard to predict in terms of timing, duration, type of eruption,

geographical or population exposure and vulnerability to different types of

hazard. This makes forward planning and risk reduction in volcanic areas

particularly problematic. Volcanic disasters can last for months and even years,

completely destroying local settlements, leaving them uninhabitable for long

1 Head, 2006; Donovan, 2009

183

periods after the eruption has ended. The 1995-1999 eruption of Soufriere Hills

Volcano in Montserrat, for example, involved a slow, incremental escalation of

volcanic activity and associated hazards, after several years of precursory seismic

activity1. More than 15 years after the eruption began it is still not considered to

be over, but none of the scientists involved in monitoring the volcano would have

assigned a high probability to this outcome at the start of the eruption. In Peru, the

2006–2008 eruption of the Ubinas volcano was the first long-lasting crisis that the

Peruvian civil authorities had to cope with, and as such is has provided important

lessons for other areas with active volcanoes2. In both these examples, critical

lessons were learned by policy-makers during the crisis periods with regard to

communicating with the public and managing large-scale evacuations.

An additional consideration – and one that is critical to disaster risk

governance – is the number of volcanoes globally that have no record of a

historical eruption. Exposed populations are likely to discount the risk of a

volcanic disaster occurring if they have no experience of eruptions, and without

public demand governments are unlikely to priorities DRM3. Furthermore,

secondary volcanic hazards can occur in the absence of an eruption, creating more

complex exposure and risk dynamics, challenging existing institutional

arrangements. Intense rainfall during Hurricane Mitch in October 1998, for

example, produced a lahars flow on the Casita volcano in Nicaragua that

destroyed two towns, killing over 2,500 people4.

Despite presenting very peculiar challenges for collective action, the

governance context has received very little attention in studies of volcanic

disasters because of the lack of interdisciplinary research in this field. There is

however a growing awareness among the natural hazards community that social

science and interdisciplinary perspectives are needed in order for hazards research

to be relevant and applicable to disaster managers. There are encouraging signs

1 Kokelaar, 2002: 5

2 Rivera, et al. 2010

3 Maskrey, 1989

4 Kerle et al., 2003

184

that volcanology journals are becoming increasingly supportive of articles on

decision-making in volcanic emergencies that use social science theories and

methodologies.

Pre-crisis period, in which action may be taken to mitigate existing and

anticipate future risk, such as land-use planning, retrofitting roofs, the

development and enforcement of building codes, education and training

programmes. These can be carried out on the basis of risk assessments. Land use

planning is a prospective tool that can be used to prevent or limit construction in

unsafe areas, while relocation and rezoning of space is a corrective tool to reduce

existing exposure to hazards. Education on early warning systems is a reactive

measure but education related to building practice that reduces ash entry into

homes is a risk management activity that anticipates and reduces risk in the future.

Crisis period, which we can sub-divide into: a) start of the crisis and

potential long period of unrest (often characterised by seismic activity), which can

be treated as preparedness phase; and b) heightening of the crisis, usually initiated

by an eruption, prompting emergency response activities to reduce negative

impacts on people, such as food aid and shelter provision.

Post-crisis period, characterised by short and longer-term recovery

measures (the first of which may commence during the crisis period) to restore

livelihoods and infrastructure as well as reduce future losses and promote

sustainability1. These corrective and prospective risk reduction measures are more

likely to occur in the post-crisis period than before an event has occurred, for

reasons outlined below and in the next section.

These three temporal phases may overlap and are not necessarily

demarcated by the hazard itself; nor do they represent a cyclical shift in the social

system (from stability-to crisis-returning to a stable state). Indeed, the concept of

a disaster cycle has been heavily criticised by social scientists for representing

1 Alexander 2002; Tierney 2012

185

disasters as temporary interruptions of a linear development process, after which

victims‘ lives return to normal1. In fact we can often observe hysteresis or

irreversibility, rather than cyclicality, in environmental and social systems

following perturbations2. Disasters can act as catalysts promoting policy change

by highlighting previous failures. For instance, the 1985 Mexico City earthquake

promoted the creation of a coordinated institutional structure for disaster

management3. Although the federal government had an emergency plan prior to

the earthquake it was simplistic and inadequate, leaving government agencies

with no idea how to act.

These disaster risk/ DRM phases may however represent important

differences in terms of governance arrangements. Different social norms govern

collective action to reduce vulnerability over the longer term (pre-crisis) than

those responsible for mobilising emergency response during a crisis4.

Organised responses to disaster risk:

The Researcher Propose that collective action to reduce disaster risk may

be different in important ways from interventions in sectoral issues such as health

and education. Vulnerability to geo-physical and hydro-meteorological events is

multi-dimensional and dynamic, as well as spatially and temporally contingent,

and is therefore inadequately addressed through linear policy-making5. Like

sectoral policy issues, however, DRM has some public good characteristics. For

example, the market does not provide sufficient construction of robust levees

because individuals and communities do not take into account the flood protection

benefits that these might offer to others. At the same time, people may construct

levees that protect themselves, with a negative external impact on others, such as

those who live outside the embankments. Other aspects of DRM like early

warning systems, on the other hand, display characteristics of non-rivalry –

1 Christoplos et al. 2001; Hewitt 1983; Twigg 2004

2 Whitten et al. 2012

3 Quarantelli 1993

4 Tierney 2012

5 Rashed and Weeks, 2003

186

whereby consumption by one individual does not reduce the availability of the

good to others – and non-excludability, so people cannot be excluded from using

the good. For all these reasons, and because states have a moral and often legal

duty to protect their citizens, DRM is generally considered to be a government

responsibility, albeit with private sector and civil society participation in delivery

and standard setting, and as such has been influenced by broader thinking on

public service delivery1.

Disasters as collective action problems:

The Researcher Propose that disasters present collective action problems

because the effective delivery of DRM requires contributions from multiple

actors, but the perceived cost to individuals and governments of investing in

DRM is often greater than the perceived benefit. These motivational challenges

often prevent action from being taken to reduce risk. Nonetheless, the mix of

incentives and disincentives may vary between DRM activities. There are often

economic disincentives to prospective risk reduction: for example, governments

have incentives to allow property developers to build on the coast in hurricane-

prone areas, destroying the mangroves that offer natural protection against storm

surge, because of the high value of these properties and the tax revenues. On the

other hand, corrective risk management projects, such as relocation of settlements

or retrofitting of buildings, are of enormous value to the construction sector and

can be lucrative for local politicians, despite the fact that housing solutions and

sites offered to low-income families are often inappropriate.

In addition to the trade-offs identified above, the International Panel for

Climate Change (IPCC) report Managing the risk of extreme events and disasters

to advance climate change adaptation identifies a number of other economic,

political and psychological constraints on effective DRM provision2.

1 Wilkinson, 2012a

2 Field et al., 2012

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• Underestimation of the risk: even when governments are aware of the risks, they

often underestimate the likelihood of the event occurring

• Budget constraints: particularly when the upfront costs are high, governments

will often focus on short-run financial goals, rather than on the potential long-

term benefits, in the form of reduced risks

• Difficulties in making trade-offs: many governments are not accustomed to

using cost-benefit analysis methods that compare upfront costs with expected

discounted benefits in the form of a reduction in future losses

• Procrastination: governments may delay making a decision when faced with

ambiguous choices

• Samaritan‘s dilemma: the expected availability of external post-disaster support

can undermine ex-ante DRM measures when there are no incentives

• Politician‘s dilemma: the benefits of public investment in DRM will not be

visible quickly (and maybe not during a politician‘s term in office), especially

when hazards are infrequent, and this reduces political will.

Disaster Management: India

The Researcher Propose that the Government of India in recognition of the

importance of disaster management as a national priority had set up a High

Powered committee (HPC) in August 1999 and a National Committee on Disaster

Management (DM) after Gujarat earthquake for making recommendation on the

preparation of DM plans and for suggestion effective of mitigation mechanism.

Recommendation of the HPC laid the foundation for DM framework in India.

The National Disaster Management Authority (NDMA) was created under

the chairmanship of Hon‘ble Prime Minister of India as the apex body for DM in

India. Similarly, such authorities at the states levels are headed by the Chief

Ministers or Governors as the case may be. Also, the District Disaster

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Management Authorities are headed by District collectors and co-chaired by the

elected representatives of the respective district. With a Purpose to tackle these

issues very seriously, a provision is made to make such highest government

authorities to head such departments. The Act Also mandates the creation of the

Nation Disaster Response Force (NDRF) for specialized response and the

National Institute of Disaster Management (NIDM) for institutional capacity

development. These bodies have been set up to facilities the paradigm shift from

the hitherto relief-centric approach to a more proactive, holistic and integrated

approach of strengthening disaster preparedness, mitigation and emergency

response.

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5.3 Disaster risk governance in Tsunamis’ areas:

General Measures:

The Researcher Propose that adopting integrated multi-hazard approach

with emphasis on cyclone and tsunami risk mitigation in coastal areas.

Implementation of early warning system for cyclones and tsunamis. Streamlining

the relief distribution system in disaster affected areas. Design, practice and

implementation of evacuation plans with emphasis on self reliance for sustenance

with the locals (coastal community) Component on planning for reconstruction

and rehabilitation should be added in disaster management plans at all levels.

Emphasis on mental health and to socio-psychological issues should be accorded

in every plan. Identification and strengthening of existing academic centers in

order to improve disaster prevention, reduction and mitigation capabilities.

Capacity building programmes to be taken up on priority basis such as:

Training of all concerned including community

Public awareness programmes

Enhancing capabilities of the Institutes working in field of disaster

mitigation and management

Structural Measures:

1. Construction of cyclone shelters

2. Plantation of mangroves and coastal forests along the coast line

3. Development of a network of local knowledge centers (rural/urban) along the

coast lines to provide necessary training and emergency communication during

crisis time (e.g. centers developed by M.S. Swaminathan Foundation in

Pondicherry)

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4. Construction of location specific sea walls and coral reefs in consultation with

experts

5. Development of break waters along the coast to provide necessary cushion

against cyclone and tsunami hazards

6. Development of tsunami detection, forecasting and warning dissemination

centers

7. Development of a ―Bio-Shield‖ - a narrow strip of land along coastline.

Permanent structures should come up in this zone with strict implementation of

suggested norms. Bio-Shield can be developed as coastal zone disaster

management sanctuary, which must have thick plantation and public spaces for

public awareness, dissemination and demonstration.

8. Identification of vulnerable structures and appropriate retrofitting for

tsunami/cyclone resistance of all such buildings as well as appropriate planning,

designing, construction of new facilities like:

Critical infrastructures e.g. power stations, warehouses, oil and

other storage tanks etc. located along the coastline.

All other infrastructure facilities located in the coastal areas

Public buildings and private houses

All marine structures

Construction and maintenance of national and state highways and

other coastal roads

Non-Structural Measures:

The Researcher Propose that Strict implementation of the coastal zone

regulations (within 500 m of the high tide line with elevation of less than 15 m

above m.s.l. Mapping the coastal area for multiple hazards, vulnerability and risk

analysis up to taluka /village level. Development of Disaster Information

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Management System (DIMS) in all the coastal states. Aggressive capacity

building requirements for the local people and the administration for facing the

disasters in wake of tsunami and cyclone, ‗based on cutting edge level‘

Developing tools and techniques for risk transfer in highly

vulnerable areas

Launching a series of public awareness campaign throughout the

coastal area

Training of local administration in forecasting warning

dissemination and evacuation techniques

Awareness generation and training among the fishermen, coast

guards, officials from fisheries department and port authorities and

local district officials etc., in connection with evacuation and post

tsunami storm surge management activities. Regular drills should

be conducted to test the efficacy of the DM plans.

Studies focusing on the tsunami risk in India may be taken under

NCRM project.

Actions Required in Coastal Areas for Protection against Tsunami / cyclone

mitigation

The Researcher Propose that to achieve the satisfactory level of disaster

mitigation in coastal areas, following activities need to be carried out:

Revision of Coastal Zone Regulation Act in wake of tsunami storm

surge hazards and strict implementation of the same. The current

Coastal Regulations Zone (extract) is attached as Appendix A to

this chapter. This responsibility may be given to respective state

disaster management authorities. A special task force for this

purpose may be constitutes comprising the representatives from

various departments of the government and other relevant

organizations (e.g. Departments of Forestry, Fisheries, Soil

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Conservation, Town and Country Planning Organization, Navy,

Coast Guard and IMD etc.)

A state of the art EOC may be established within the authority for

monitoring purpose.

Initiating disaster watch (bay watch) safety measures along

important beaches in the country, providing round the clock

monitoring, warning and lifeguard facilities etc.

Organization of sensitization workshops on cyclone/tsunami risk

mitigation in various states for senior bureaucrats / politicians for

these states.

Organizing drills on regular basis to check the viability of all plans

and to check the readiness of all concerned

Training of professionals, policy planners and others involved with

disaster mitigation and management programmes in the states

Retrofitting of important buildings:

I. Fire stations / police stations/ army structures/ hospitals

II. VIP residences / offices/ railways, airport, etc.

III. Schools/colleges

IV. Hazardous industries

V. Other critical structures (i.e. power stations, warehouses, oil and

other storage tanks etc)

Designing incentives: Providing legislative back up to encourage people to

adopt cyclone, tsunami resistant features in their homes e.g. tax rebate in terms of

house tax and/or income tax.

Developing public –private partnerships.

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Tsunami Effects and Design Solutions:

Phenomenon of Inundation

EFFECT DESIGN SOLUTION

Flooded basement Choose sites at higher elevations

Flooding of lower floors Raise the buildings above flood elevation

Flooding of mechanical electrical &

communication system & equipment

Do not stack or install vital material or

equipments on floors or basement lying

below tsunami inundation level

Damage to building materials &

contents

Protect hazardous material storage

facility located in tsunami prone area.

Contamination of affected areas with

water borne pollutants

• Locate mechanical systems &

equipments at higher location in

the building

• Use corrosion resistant

concrete & steel for the portions

of the building

Hydrostatic forces (Pressure on walls

by variation in water depth on opposite

sides

• Elevate building above flood

level.

• Provide adequate openings to

allow water to reach equal heights

inside & outside of buildings.

• Design for static water

pressure on walls.

Buoyancy floatation or uplift forces

caused by buoyancy

• Elevate building to avoid

flooding.

• Anchor building to foundation

to prevent floatation

Saturation of soil causing slope

instability and/or loss of bearing

capacity

• Evaluate bearing capacity &

shear strength of soil that support

building foundation &

embankment slopes under

condition of saturation.

• Avoid slopes or setbacks from

slope that may be destabilized

when inundated.

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Specific Design Principles for Tsunamis:

Know the Tsunami Risk at the site:

Distance from the sea

Elevation above mean sea level

Height of high tide above m. s. l.

Maximum run-up of the tsunami above the site elevation

Depth and speed of the tsunami wave for design purposes.

Role of land Use Planning:

Local Context

Understanding Trade offs

Review and update existing Safety elements

Review and update existing Land Use Elements

Review and update existing Zoning, and other regulations

Land Use Planning Strategies

Site Planning Strategies to reduce Tsunami Risk:

Avoiding by building on high ground – necessary for vital

installations

Slowing the tsunami wave by frictional techniques – forests,

ditches, slopes and beams

Deflecting the tsunami away by using angled walls – suitable for

important installations

Brute resistance through stiffened strong structural design – costly

buildings

High rise buildings with open ground storey, designed for wave

forces – Hotels, offices etc

Stilted buildings for various uses.

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Tsunami Resistant Buildings – New Developments:

Locally applicable Tsunami Hazard Information on Design

Intensities

Performance Objectives

Mandatory use of building Codes – Design Criteria

Safety under Multi-hazard environment

Qualified Engineers and Architects - knowledge about Earthquake,

Wind and Tsunami resistant planning and design

Ensure quality construction

Protection of existing buildings and infrastructure Assessment, Retrofit,

Protection measures:

Inventory of existing assets

Assessment of Vulnerability and deficiencies to be taken care of

through retrofitting

Methods of retrofitting and use in design

External protection methods from the onslaught of tsunami

Special Precautions in locating and designing infrastructure and critical

facilities:

Considerations in relocating and redevelopment of infrastructure

Considerations in relocating and redevelopment of critical

facilities

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Planning for Evacuation:

Vertical evacuation – High rise buildings, special shelters

Horizontal evacuation – Locating high grounds, building high

enough mounds

Awareness about evacuation areas and routes

The Present status of Tsunami Warnings in India:

The Researcher Propose that Tsunami is least probability event in India. As

such, there are no coral provisions of Tsunami warnings in India as yet though;

there is a good seismological network in India to record any earthquake within the

country and its neighborhood. The need of a Tsunami Warning Centre (TWC) in

India is now being conceptualized at the Government of India level.

The Department of Ocean Development in Cooperation with Departments of

Space and Science and Technology is evolving a plan of tsunami warning system

in the Bay of Bengal and the Arabian Sea. The data from observing points to

Warning Centre(s) will be sent through satellite links, Specific systems called

Deep Ocean Assessment and Reporting of Tsunamis (DART) using Bottom

Pressure Recorder, acoustic modem, acoustic release system, and battery pack

bolted to platform and float action and recovery aids will be deployed.

International Status of Tsunami Warning and Communication System:

The Researcher Propose that present techniques of Tsunami prediction are

severely limited. The only way to determine, with certainty, if an earthquake is

accompanies by a Tsunami, is to note the occurrence and epicenter of the

earthquake and then detect the arrival of the Tsunami at a network of tide stations.

While it is possible to predict when a Tsunami will arrive at coastal locations, it is

not yet possible to predict the wave height, number of waves, duration of hazard,

or the forces to be expected from such waves at specific locations.

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Tsunami Warning System is based on the concept that Tsunamis travel at

much slower velocity (500 to 700 km per hour or 0.20 km/sec) as compared to

seismic waves (6 to 8 km per second). That is seismic waves move 30 to 40 times

faster than Tsunami waves. Thus, after the occurrence of a damaging earthquake

and quick determination of epicenter, warning time of a few minutes to 2 to 3

hours is available depending upon the distance from the epicenter to the coast

line. This time can be utilized for warning the coastal community if quick

detection and rapid communication systems are established.

Tsunami Warning System:

The Researcher Propose that following most common methods of detection is in

use:

Japan has a network of land/sea sensors that records seismic activity and

feeds information to a national agency able to issue evacuation warnings

within a minute of occurrence of any earthquake. Earthquake warning

issued by Japan Meteorological Agency are relayed via satellite to the

Municipal offices and automatically broadcast from several sets of

loudspeakers.

Pacific Ocean issues warnings of tidal waves heading in a particular

direction.

Presently land and sea based sensors connected to satellite based link are

available.

Satellite telemetry is used for data collection and dissemination; receive

and display of Tsunami warning utilizing existing Geostationary

operational Environmental Satellite (GOES) and Data Collection

Interrogation System (DCIS). An earthquake activates seismic

instrument, which transmits signal to the GOES platform which responds

automatically transmitting an alert code to an active device at warning site.

Developing Tsunami and earthquake data base verification, Tsunami

model, preparation of hazard assessment maps for the coast line combing

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historical and modeling result, establishment of seismic and tidal sensors

using satellite telemetry to provide early warning information.

Extensive network of seismic and tidal station, as well as communication

systems, to ensure that the warning information is prompt and accurate.

System performs with detection of an earthquake, which has required

magnitude to trigger the alarm attached to the seismograph. The alarm

thresholds are set so that ground vibrations of the amplitude and duration

associated with an earthquake of approximate amplitude 6.5 or greater or

Richter scale anywhere in Pacific will cause them to sound.

Tsunami Warning Centers:

The Researcher Propose that as part of an international cooperative effort

to save lives and protect property, the National Oceanic and Atmospheric

Administration‘s (NOAA) National Weather Service operates two Tsunami

warning centers. The Alaska Tsunami Warning Center (ATWC) IN Palmer,

Alaska, serves as the regional Tsunami Warning Center for Alaska, British

Columbia, Washington, Oregon, and California.

The Pacific Tsunami Warning Center in Ewa Beach, Hawaii, serves as the

regional Tsunami Warning Centre for Hawaii and as a national/international

warning center for Tsunamis that pose a Pacific-wide threat. These international

warning efforts become a formal arrangement in 1965 when PTWC assumed the

international warning responsibilities of the Pacific Tsunami Warning System

(PTWS). The PTWS is composed of 26 international Member States that are

organized as the International Coordination Group for the Tsunami Warning

System in the Pacific.

Tsunami Watch and Warning Dissemination:

The Researcher Propose that the objective of the PTWS is to detect,

locate, and determine the magnitude of potentially Tsunamigenic earthquake

occurring in the Pacific Basin or its immediate margins. Earthquake information

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is provided by seismic stations operated by PTWC, ATWC, the U.S. Geological

Survey‘s National Earthquake Information Centre and international sources. If

the location and magnitude of an earthquake meet the known criteria for

generation of a Tsunami, a Tsunami warning is issued to warm of an imminent

Tsunami hazard. The warning includes predicted Tsunami arrival times at

selected coastal communities within the geographic area defined by the maximum

distance the Tsunami could travel in a few hours. A Tsunami watch with

additional predicted Tsunami arrival times is issued for a geographic area defined

by the distance the Tsunami could travel in a subsequent time period. If a

significant Tsunami is detected by sea-level monitoring instrumentation, the

Tsunami warning is extended to the entire Pacific Basin. Seal level (or tidal)

information is provided by NOAA‘s National Ocean Service, PTWC, ATWC,

university monitoring networks and other participating nations of the PTWS. The

International Tsunami Information Center, part of the Intergovernmental

Oceanographic Commission, monitors and evaluates the performance and

effectiveness of the Pacific Tsunami Warning System. This effort encourages the

most effective data collection, data analysis, Tsunami impact assessment and

warning dissemination to all TWS participants.

Tsunami Warning Dissemination:

The Researcher Propose that Tsunami watch, warning and information

bulletins are disseminated to appropriate emergency officials and the general

public by a variety of communication methods:

Tsunami watch, warning and information bulletins issued by

PTWC and Atlantic Tsunami Warning Centre (ATWC) are

disseminated to local, state, national and international users as well

as the media. These users, in turns, disseminate the Tsunami

information to the public, generally over commercial radio and

television channels.

200

The NOAA Weather Radio System, based on a large number of

VHF transmitter sites, provides direct broadcast of Tsunami

information to the public.

The US Coast Guard also broadcasts urgent marine warnings and

related Tsunami information to coastal users equipped with

medium frequency (MF) and very high frequency (VHF) marine

radios.

Local authorities and emergency managers are responsible for

formulating and executing evacuation plans for areas under a

Tsunami warning. The public is advised to stay-turned to the local

media for evacuation orders and latest Tsunami warnings. People

are advised not to return to low lying coastal areas until all clear

signals are issued from the Warning Centre.

Some concepts of Work Plan for the Tsunami Warning System in India:

Assumption: Least probability event. Return period once after

several hundred years. No parallel in recorded history like Tsunami

of 26 December 2004. Proposed system should be sustainable and

cost - effective.

Observational system should be of multi use type (Oceanography,

Meteorology, Geophysics)

Policy decision: Codal Provision to issue Tsunami warning.

Identification/Establishment of Nodal Department

Identification of Vulnerable area

Fixation of critical value for the issuance of Tsunami warnings

(Magnitude 7.0 or above in Richter Scale )

Assessment of Present Capacity: (observation network and

Communication of data & warnings, gap areas and needs)

Cost effective and sustainable communication system (Radio and

Satellite based communication)

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Awareness Programme – Targets

For Scientific communities (Those Researchers connected with

aspects of Tsunami)

Coordinators and Operators of Warning System

Disaster Managers

General Public

Research

Compilation of historical records

Development of model to predict probable maximum Tsunami

heights along different coastal locations in India.

Propagation time charts

Mitigation measures:

The Researcher Propose that since the return period of destructive

Tsunami are very large, Tsunami mitigation measure should be considered along

with mitigation measure of other natural hazards like tropical cyclone, coastal

flooding, coastal erosion (due strong monsoon and other natural hazards) etc.

However, specific Tsunami protective measures may be undertaken for the vital

coastal installations like important ports, nuclear plants along the coast high value

coastal installation properties.

Tsunami Disaster Management: India

The Researcher Propose that the Disaster Management Act, 2005 (DM

Act, 2005) lays down institutional and coordination mechanism for effective

disaster management (DM) at the national, state and district levels. the

Government of India (GOI) in recognition of the importance of disaster

management as a national priority had set up a High Powered committee (HPC) in

August 1999 and a National Committee on Disaster Management (DM) after

Gujarat earthquake for making recommendation on the preparation of DM plans

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and for suggestion effective of mitigation mechanism. Recommendation of the

HPC laid the foundation for DM framework in India.

The National Disaster Management Authority (NDMA) was created under

the chairmanship of Hon‘ble Prime Minister of India as the apex body for DM in

India. Similarly, such authorities at the states levels are headed by the Chief

Ministers or Governors as the case may be. Also, The District Disaster

Management Authorities (DDMA) are headed by District collectors and co-

chaired by the elected representatives of the respective district. With a Purpose to

tackle these issues very seriously, a provision is made to make such highest

government authorities to head such departments. The Act Also mandates the

creation of The Nation Disaster Response Force (NDRF) for specialized response

and the National Institute of Disaster Management (NIDM) for institutional

capacity development. Standing National Crisis Management Committee

(SNCMC) this committee was constituted for effective co-ordination and

implementation of response and relief measures in the wake of disasters. The

committee consists secretaries and chairman of different departments under the

Government of India. These bodies have been set up to facilities the paradigm

shift from the hitherto relief-centric approach to a more proactive, holistic and

integrated approach of strengthening disaster preparedness, mitigation and

emergency response.

New institutional mechanisms:

The Researcher Propose that the existing mechanisms had based on post-

disaster relief and rehabilitation and they have proved to be robust and effective

mechanisms in addressing these requirements. The changed policy/approach,

however, mandates a priority to full disaster aspects of mitigation, prevention and

preparedness and new institutional and policy mechanisms are being put in place

to address the policy change.

203

It is proposed to constitute a National Emergency Management Authority

at the National level. The High Powered Committee on Disaster Management

which was set up in August, 1999 and submitted its Report in October, 2001, had

inter alia recommended that a separate Department of Disaster Management be

set up in the Government of India. It was, however, felt that conventional

Ministries/Departments have the drawback of not being flexible enough

especially in terms of the sanction procedures. The organization at the Apex level

will have to be multi-disciplinary with experts covering a large number of

branches. The National Emergency Management Authority has, therefore, been

proposed as a combined Secretariat/Directorate structure – a structure which will

be an integral part of the Government and, therefore, will work with the full

authority of the Government while, at the same time, retaining the flexibility of a

field organization. The National Emergency Management Authority will be

headed by an officer of the rank of Secretary/Special Secretary to the Government

in the Ministry of Home Affairs with Special Secretaries/Additional Secretaries

from the Ministries/Departments of Health, Water Resources, Environment &

Forests, Agriculture, Railways, Atomic Energy, Defense, Chemicals, Science &

Technology, Telecommunications, Urban Employment and Poverty Alleviation,

Rural Development and India Meteorological Department as Members of the

Authority. The Authority would meet as often as required and review the status of

Warning systems, mitigation measures and disaster preparedness. When a disaster

strikes, the Authority will coordinate disaster management activities. The

Authority will be responsible for:-

i. Coordinating/mandating Government‘s policies for disaster

reduction/mitigation.

ii. Ensuring adequate preparedness at all levels in order to meet disasters.

iii. Coordinating response to a disaster when it strikes.

iv. Coordination of post disaster relief and rehabilitation.

The various prevention and mitigation measures outlined above are aimed at

building up the capabilities of the communities, voluntary organizations and

204

Government functionaries at all levels. Particular stress is being laid on ensuring

that these measures are institutionalized considering the vast population and the

geographical area of the country. This is a major task being undertaken by the

Government to put in place mitigation measures for vulnerability reduction. This

is just a beginning. The ultimate goal is to make prevention and mitigation a part

of normal day-to-day life. The above mentioned initiatives will be put in place

and information disseminated over a period of five to eight years. We have a firm

conviction that with these measures in place, we could say with confidence that

disasters like Orissa cyclone and Bhuj earthquake will not be allowed to recur in t

is country; at least not at the cost, which the country has paid in these two

disasters in terms of human lives, livestock, loss of property and means of

livelihood.

205

Chapter VI: Conclusion

Earthquake, Volcano and Tsunami have always been serious challenges

before the world the scenario is all the more grim now with population explosion

and uncontrolled development. The Government of India and United Nations has

made an attempt to by making legal provision for natural disaster such as

Earthquake, Volcano and Tsunami. The Government of India enacted The

Disaster Management Act, 2005 and also constitutes authorities have rights and

duties for disaster mitigation. However development of a regulatory framework

and institutionalization alone is not sufficient for dealing with disasters. It is

necessary for the government to allot adequate funds and give attention to the

issue of disaster management from the broader prospective of protection of

human and human rights, all within the framework of good governance and state

responsibility. The need of hour is to focus on sustainable development that

balances the needs of the people without destroying the delicate balance of nature.

206

Chapter VII: Recommendation and Suggestions

1. Create accurate and informative database regarding the collection of

information of availability of various safety and other equipment.

2. Organizational supply chain or link must be established between the

NGO‘s and such other institutional and volunteers in the field.

3. Up to date information must be collected and recorded regarding

current scientific researcher and technology available on the topic.

4. Drill will have to be organized to society and volunteers prepared for

dealing with such emergencies.

5. Communication infrastructure and its skill must be developed by using

all possible Medias.

6. Government should pass legal regulation for construction activities

near Volcano and Tsunami affected areas and strict implementation of

such regulation.

7. NGO‘s should take part to spread awareness about the effect of

Earthquake, Volcano and Tsunami and educate the people about safety

precautions from such disaster.

8. Victims of the disaster should be treated with humanity and it is a

responsibility of government to come up with effect rehabilitation

policy for such victims.

9. Victims are the main culprit in case of India because authorities are not

bothering about their problem and corrupt government officials are

more interested in bribe instead of helping disaster victims, this

condition should be change in future.

10. National and international regime should enact policy and legal

regulation for environment protection from the effect of Earthquake,

Volcano and Tsunami. This is possible only if every nation in world

should co-ordinate with each other at time of nature disaster such as

Earthquake, Volcano and Tsunami.

207

Abbreviations

CCA - Climate change adaptation

DFID - Department for International Development

DRM - Disaster risk management

HFA - Hyogo Framework for Action

IPCC - Intergovernmental Panel on Climate Change

NGO - Non-governmental organization

PEA - Political economy analysis

STREVA - Strengthening Resilience in Volcanic Areas

UNDP - United Nations Development Programme

UNISDR - United Nations International Secretariat for Disaster

Reduction

DM - disaster management

HPC - High Powered committee

NDMA - The National Disaster Management Authority

NDRF - The Nation Disaster Response Force

NIDM - National Institute of Disaster Management

SNCMC - Standing National Crisis Management Committee

DDMA - The District Disaster Management Authorities

208

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214

Synopsis

Earthquake, Volcano and Tsunami: The Ultimate Environment

Destroyers

Bharat Mahendra Shah

Role No: 53

Group VI - Environment and Legal Order (Sem- VI)

Introduction:

The Researcher is researching on effect of Earthquake, Volcano and

Tsunami. These are the ultimate destroyer of the Natural Environment and

Human Environment. We usually think of the ground and the oceans are

peaceful things. The ground lies quietly beneath our feet, and the ocean laps

gently against the shore. But forces deep within the Earth can suddenly destroy

that peacefulness. These forces cause violent shakings called earthquakes;

explosions of ash, gases, and hot rocks called volcanoes; and huge waves called

tsunamis.

(iv) Earthquake: The plates usually move very slowly. But sometimes

large pieces of the plates get caught. The plates keep trying to move,

but these large blocks of rock hold them back. The pressure and

energy build up. Then, suddenly, the rocks give way, releasing all that

pressure and energy. The plates jerk forward, and the ground shakes.

Far above, on the surface, people feel an earthquake. In a small

earthquake, the ground shakes a little, causing some hanging objects

to swing. Tree branches sway, as if there were a gentle breeze. Some

215

earthquakes are so small that we do not notice them. But sometimes

the shaking is so strong that buildings crumble, bridges collapse, and

large cracks open in the ground over large areas.

(v) Volcano: A volcano occurs wherever magma from deep inside the

Earth comes out through a crack in the surface. Volcanoes usually

happen near the edges of the plates, where there are many cracks and

thin spots where the magma can leak out. When the magma pours

onto the surface, it hardens, often piling up into a mountain.

Sometimes, the liquid rock flows peacefully out across the land. This

is how many of the active volcanoes on the Hawaiian Islands behave.

(vi) Tsunami: Tsunamis are huge waves caused by earthquakes or

volcanoes. They used to be called ―tidal waves.‖ But the word ―tidal‖

means something to do with the ocean‘s normal tides, and tsunamis

have nothing to do with the tides. Tsunamis can be as high as a

football field is long. They are the largest waves in the world.

Research Methodology: Doctrinal Research

Hypothesis:

Earthquake, Volcano and Tsunami has significant effect on our natural and

human environment which causes huge damages to life and property.

Chapterisation:

Chapter 1: Introduction

Chapter 2: Concept

Chapter 2.1: Concept of Earthquake

216

Chapter 2.2: Concept of Volcano

Chapter 2.3: Concept of Tsunami

Chapter 3: Effects

Chapter 3.1: Effects of Earthquake

Chapter 3.1: Effects of Volcano

Chapter 3.1: Effects of Tsunami

Chapter 4: Safety Precautions

Chapter 4.1: Safety Precautions during earthquake

Chapter 4.2: Safety Precautions during volcanic eruptions

Chapter 4.3: Safety Precautions during Tsunami

Chapter 5: Legal Framework

Conclusion: Earthquake, Volcano and Tsunami have always been serious

challenges before the world the scenario is all the more grim now with

population explosion and uncontrolled development. The need of hour is to

focus on sustainable development that balances the needs of the people without

destroying the delicate balance of nature.

217

Bibliography:

(i) Books:

Environmental Law - Dr.Amod S.Tilak.

Law and Environment - P. Leelakrishnan.

Legal Research Methodology - Dr S. R. Myneni

Environmental Protection, Law and Policy in India - Kailash

Thakur.

(ii) News Paper reports:

Times of India.

Free Press Journals.