What is Earth Science? Earth science: The study of ‘Earth Systems’. Astronomy: The study of...

What is Earth Science?

Earth science: The study of ‘Earth Systems’. Astronomy: The study of objects beyond

Earth. Meteorology: The study of the air

surrounding Earth. Geology: The study of materials that make

up Earth. Oceanography: The study of Earth’s

oceans.

What are the major ‘Earth Systems’?

Lithosphere

Outer shell (crust) of the Earth, including all rocks.

What are the major ‘Earth Systems’? Hydrosphere

All water on Earth…both saltwater AND freshwater.

Oceans Lakes Rivers Seas Glaciers


Atmosphere

The blanket of gases that surround Earth. Mostly nitrogen and oxygen!


Biosphere

All living things on Earth. This is what you will study in BIOLOGY!!!

Why is Earth Science important to us?

We LIVE on the lithosphere.

We BREATHE part of the atmosphere.

We DRINK part of the hydrosphere.

What is the Scientific Method?

Question Hypothesis Experiment

Procedure Independent Variable…what we CHANGE (1) Control…what we keep the SAME

Observations Results Conclusion

What is cartography?

Cartography: The science of mapmaking. Lines in the form of a grid are usually used

as a basis to create maps.

What are map lines called?

Lines that run up-and-down (North and South) on a map are called lines of LONGITUDE.

Lines that run side-to-side (East and West) on a map are called lines

of LATITUDE.

What are map lines called?

The central line of LONGITUDE on Earth is the PRIME MERIDIAN.

The central line of LATITUDE on

Earth is the EQUATOR.

How is latitude measured?

The EQUATOR is 0 degrees latitude.

The NORTH POLE is 90 degrees North.

The SOUTH POLE is 90 degrees South.

How is longitude measured?

The PRIME MERIDIAN is 0 degrees longitude.

The INTERNATIONAL DATE LINE is 180 degrees longitude.

All other longitude measurements are 1-179 degrees West OR East of the Prime Meridian.

Where is North Carolina?

North Carolina is located at approximately 35 degrees North (latitude) and 80 degrees West (longitude).

35o N, 80o W

What are time zones?

Earth is divided into 24 time zones.

Every time zone spans 15 degrees longitude.

As you travel west across a map, time shifts back ONE HOUR every 15 degrees longitude!

What are map legends?

Map Legend: explains the symbols used within a map. Solid red lines for roads Blue lines for rivers/creeks Black squares for buildings

(legend courtesy of www.sunysb.edu) (scales courtesy of www.junglephotos.com and

www.fes.uwaterloo.ca)

What is a map scale?

Map scale: displays the ratio between real-life distances and distances on a map 1cm : 20 km 1 in : 250 mi

What is a topographic map?

A topographic map measures:

SHAPE

ELEVATION


Topographic map: uses ‘contour lines’ and symbols to represent changes in elevation and features on Earth’s surface.

What are contour lines?

Contour line: a line that connects points of equal elevation.

Contour interval: the difference in elevation between two side-by-side contour lines.

What are contour lines?

The closer together contour lines are on a map, the steeper the slope is!!!

The farther apart contour lines are on a map, the gentler (flatter) the slope is!!!

What are topographic maps?


What is the contour interval? What is the elevation at Point A? B? C?


What is the contour interval? What is the highest elevation on this map? What is the lowest elevation on this map?


Where is the ‘flat’ section of this map? Where is the ‘sloped’ section of this map?

What is the basis of chemistry? The atom: “unable to be cut”; the basic

unit of matter Proton (+)

Within nucleus Neutron (O)

Within nucleus Approximately the same mass of a proton.

Electron (-) Orbits around nucleus 1/1840 the mass of a proton!!!

What is the Periodic Table?

Atomic Number # of protons in an atom

Mass Number # of protons + # of neutrons in an atom Mass Number – Atomic Number = # of

neutrons in an atom

The Periodic Table is organized numerically by atomic number.

Atomic # Mass # # of p+ # of n # of e-

Carbon 6 12 6 6 6

Oxygen 8 16 8 8 8

Chlorine 17 35 17 18 17

Titanium 22 48 22 26 22

Gold 79 197 79 118 79

What are atoms?

Atoms (elements) are usually NEUTRAL…they have the same number of protons as electrons.

Isotopes have different numbers of neutrons than regular elements. Therefore, they have a different mass

number!!! Ions have different numbers of electrons

than regular elements.

What is a compound?

A chemical compound is a substance formed by the chemical combination of two or more elements. NaCl H2O

The MOLECULE is the smallest unit of compounds.

What are the two types of chemical bonds?

Ionic Bonds Electrons are TRANSFERRED between

atoms. “+ vs. –” attraction

Covalent Bonds Electrons are SHARED between atoms.

What are properties of the water molecule?

Water is polar…there is a – charge on the oxygen end and a + charge on the hydrogen end.

HYDROGEN BONDS can form between water molecules (and anything else with H,N,O)

What are properties of the water molecule?

Cohesion: water attracted to water

Adhesion: water attracted to glass

Types of Substances Element: A substance that can’t be broken down

into simpler substances…made of the same type of atom. (Carbon, Hydrogen, etc.)

Compound: The combination of two or more elements. (Water—H2O and Salt—NaCl)

Mixture: Salt and Pepper Can be PHYSICALLY separated!!!

Solution: Mixture that cannot be physically separated…particles are DISSOLVED in a liquid. Solute (salt) + Solvent (water) = Solution (saltwater)

What are acids, bases, and pHs?

In a solution, H20 dissolves to form H+ and OH-.

pH measures the ratio of H+ to OH- ions in a solution.


Acid pH 0.1 to 6.9 More H+ ions than OH- ions

Base pH 7.1 to 14 More OH- ions than H+ ions


Neutral Substance pH 7 PURE WATER IS NEUTRAL!!! H+ and OH- concentration is equal

What is a mineral?

Mineral: Naturally occurring, inorganic solid. Composed of specific chemicals Has a definite crystalline structure Inorganic: NOT living

What is a mineral?

There are over 3000 minerals in Earth’s crust.

Why are they important? First tools made of IRON. First buildings (Egypt/Greece) made of

CALCITE. Many civilizations thrived with GOLD and

SILVER.

What is a mineral?

Mineral crystals can be composed of SIX different shapes. Cubic Tetragonal Hexagonal 3 others

How do minerals form?

1) Minerals can form from cooling MAGMA.

If magma cools SLOWLY underground, then the mineral crystals will be LARGE.

If magma cools QUICKLY above ground, then the mineral crystals will be SMALL.

How do minerals form?

2) Minerals can form from water solution. The water can become OVERFILLED with

mineral particles, and these particles can ‘settle out’ of solution.

OR The water can contain mineral particles,

the water evaporates, and the minerals remain.

What are major mineral groups?

1) Silicates Oxygen and Silicon 96% of all minerals Quartz and feldspar

2) Carbonates Carbonate (CO3) and Oxygen Calcite and dolomite

What are major mineral groups? 3) Oxides

Oxygen and a metal Hematite and magnetite

4) Halides Salts

5) Native Elements Silver, copper, gold

6) Sulfates 7) Sulfides

How do you ID minerals?

1) Color Least reliable way to ID.

2) Luster The way that a mineral reflects light from

its surface. Metallic (shiny) or NONMETALLIC (dull)

3) Texture How does a mineral feel to the touch. Smooth, rough, greasy, glassy


4) Streak The color of a mineral when it is broken up

and powdered. Fool’s gold…greenish-black streak Gold…yellow streak

5) Hardness A measure of how easily a mineral can be

scratched. Mohs scale…1-10


6) Cleavage When a mineral breaks smoothly along flat

edges. 7) Fracture

When a mineral breaks along rough/jagged edges.

8) Density D = Mass / Volume Some minerals are more dense than others.

How are minerals used?

Minerals are used to make… Computers Cars TVs Desks Roads Buildings Jewelry Paints Sports equipment Medicines

How are minerals used?

Ore: a mineral that contains something that can be mined for profit. Hematite is an ore that contains IRON. Bauxite is an ore that contains

ALUMINUM.

Gem: A mineral that is valuable…rare and pretty. Ruby, emerald, diamond, etc.

(5.1) What are igneous rocks?

Igneous rocks: rocks that are formed from the crystallization of magma

Extrusive igneous rocks: have small mineral grains; form when lava cools quickly on Earth’s surface

Intrusive igneous rocks: have large mineral grains; form when magma cools slowly beneath Earth’s surface

What is magma made of?

Magma is usually NOT just hot, melted rock…it is a “slushy” mix of molten rock, gases, and solid mineral crystals.

What is magma made of?

Magma is made of the following elements…

Oxygen (O) Silicon (Si) Aluminum (Al) Iron (Fe) Magnesium (Mg) Calcium (Ca) Potassium (K) Sodium (Na)

What factors affect magma formation?

Factors that affect mineral formation… 1) Temperature

The higher the temperature, the more easily rock melts!

2) Pressure The lower the pressure, the more easily

the rock melts!

What factors affect magma formation?

3) Water Content The more water in the rock, the more

easily the rock melts!

4) Mineral Composition Continental crust usually melts more easily

than oceanic crust!

(5.2) How are igneous rocks classified? 1) MINERAL CONTENT Felsic rocks: light-colored, high silica content,

contain quartz and feldspar

Mafic rocks: dark-colored, lower silica content, contain iron (Fe) and magnesium (Mg)

Ultramafic rocks: very dark-colored, very low silica content, very high levels of Fe and Mg

How are igneous rocks classified?

2) GRAIN SIZE Coarse-grained rocks Fine-grained (glassy) rocks

How are igneous rocks classified?

3) Texture

Rocks formed of well-shaped mineral crystals (perfect cubes)

Rocks formed of irregular mineral crystals

Why are igneous rocks important?

Igneous rocks are STRONG and RESISTANT TO WEATHERING, so they are used for…

Kitchen counters Gravestones/Monuments Buildings


Mineral ores are usually found within or near igneous rock!!!

Veins: mineral-rich fluid fills cracks in mountains…these cracks cool and solidify to form veins that can be mined

GOLD in SIERRA-NEVADA MOUNTAINS


Pegmatites: extremely large-grained mineral deposits found within some veins Lithium Jewels


Kimberlites: deep, pipe-like igneous rock formations A type of ULTRAMAFIC rock Often contain diamonds

(6.1) What is a sedimentary rock?

Sedimentary rock: rock formed from sediment that is cemented together

How do sedimentary rocks form?

1) WEATHERING: exposed rocks on Earth’s crust is worn away

Chemical weathering: minerals in a rock are dissolved or changed

Physical weathering: rock fragments simply break off the larger rock

THESE SMALL PIECES OF ROCK THAT BREAK OFF ARE CALLED SEDIMENTS!


2) EROSION & TRANSPORT: removal and movement of surface materials from one location to another location

Wind Moving water Gravity Glaciers


3) DEPOSITION: the ‘laying down’ of sediments on the ground (or on the bottom of a body of water).

This occurs when erosion & transport STOPS.

LARGER sediment grains deposit on the bottom, while SMALLER grains are on top.

Boulder, cobble, pebble, sand, silt, clay


4) BURIAL: sediments are buried under newer sediments

5) LITHIFICATION: the processes that transform sediments into sedimentary rocks! Usually high temperatures and pressures

resulting from deep BURIAL.

How does lithification occur?

5-A) Air and water pockets are squeezed out of the sediment.

5-B) Cementation occurs…mineral growth “glues” sediment grains into solid rock

What are some features of sedimentary rocks?

Features of sedimentary rocks include…

1) Bedding: horizontal layering Larger sediments on bottom, smaller

sediments on top.

2) Ripple marks: signal past wave (water) or wind action

What are some features of sedimentary rocks?

3) Fossils: evidence of past life

Footprints Shells Bones Plants

(6.2) How are sedimentary rocks classified?

There are THREE main types of sedimentary rocks

1) Clastic 2) Chemical 3) Organic

How are sedimentary rocks classified?

How are sedimentary rocks classified? 2) Chemical sedimentary rocks

Rocks that form when dissolved minerals settle out of a body of water (or when dissolved minerals are exposed after the water dries up).

Called EVAPORITES….found near bodies of water!

Rock salt Gypsum


3) Organic sedimentary rocks Rocks that are formed from the remains of

once-living things.

Limestone…formed from sea shells Coal…formed from dead swamp plants

Why are sedimentary rocks important?

Sedimentary rocks are important because…

1) We can learn about Earth’s history by looking at fossils that are preserved only in sedimentary rocks.

Why are sedimentary rocks important? 2) Energy sources are found in sedimentary

rocks. Coal Oil Natural gas Uranium (nuclear power) Phosphate (fertilizer) Limestone (cement) Iron (steel) Sandstone (buildings)

(6.3) What are metamorphic rocks?

Metamorphic rocks: Rocks formed from metamorphism….high pressures and high temperatures very deep within Earth. Rocks CHANGE while remaining SOLID…

they don’t melt!!

What are metamorphic rocks?

3 Types of Metamorphism

1) Regional metamorphism: high temperatures and pressures affect large areas of Earth’s crust

2) Contact metamorphism: molten rocks come in contact with solid rocks, causing temperature increases

3) Hydrothermal metamorphism: same as ‘contact’, but with hot water instead of lava


2 Types of Metamorphic Textures

1) Foliated Wavy layers and bands of minerals

2) Nonfoliated ‘Blocky’ crystal shapes instead of bands


RULE:

The higher the heat/pressure, the stronger the rock!

Metamorphic rocks are just igneous or sedimentary rocks that have been changed underground!

What is the rock cycle?

Ch. 17 Vocab: 5 terms

P. 443 (continental drift, Pangaea) P. 448 (seafloor spreading) P. 455 (theory of plate tectonics,

subduction)

Are the continents really moving?

There are 3 layers that make up Earth. Crust….rigid and rocky Mantle…like modeling clay Core…molten metal with a hard center


YES!!! Land masses are moving at high speeds (for land, at least). South America & Africa

Moving apart at 2-3 cm/year Hawaii

Moving northwest at 8-9 cm/year Mount Everest

Moving up…it is getting taller!

What is continental drift?

Alfred Wegener observed this movement, and called this land movement “continental drift”.


Continental drift: Earth’s continents had once been joined as

a single landmass called PANGAEA. About 200 million years ago, Pangaea

began to break apart to form the continents that we know today.

Why did Wegener believe in continental drift?

3 forms of evidence: 1) Rock Formations

Appalachian Mtn. rocks are same as European rocks

2) Fossils Found plant/animal fossils in weird places

3) Climate Coal in Antarctica….coal comes from tropical

swamp plants!!!


Wegener’s “continental drift” hypothesis was not accepted by most scientists….they didn’t believe that the continents were really moving.

Continental drift was not accepted until the 1960’s when new evidence was discovered!!!

What evidence led to the acceptance of continental drift?

Analysis of the ocean floor showed:

Rock samples near mid-ocean ridges (middle of the ocean) were young

Rock samples farther away from mid-ocean ridges (edges of the ocean) were old

OLD YOUNG OLD

What evidence led to the acceptance of continental drift?

Analysis of the ocean floor showed:

Level of sediment is thin in the middle of the ocean.

Level of sediment is thick at the edges of the ocean.

THICK THIN THICK

What is seafloor spreading?


Seafloor spreading: new ocean crust is formed at mid-ocean ridges…

When this crust is formed, older crust is pushed outward, which spreads out the ocean floor.


SO…..seafloor spreading explains HOW continental drift works.

The seafloor “spreads” at the middle of the ocean, and the continents are pushed away from each other. The continents are just along for the ride

that seafloor spreading provides for them!

What is plate tectonics?

The theory of plate tectonics:

Earth’s crust and upper mantle are broken into enormous, movable slabs called plates

There are 12-15 major plates on Earth

What is plate tectonics?

What are plate boundaries?

Earth’s plates come together at BOUNDARIES.

There are 3 types of boundaries.


1) Divergent boundaries

Places where two tectonic plates move apart from each other.

Mid-Ocean Ridges are divergent boundaries!!


2) Convergent boundaries

Places where two tectonic plates move toward each other.


Three types of convergent boundaries Oceanic-Oceanic Oceanic-Continental Continental-Continental

At oceanic-oceanic AND oceanic-continental convergent boundaries, SUBDUCTION occurs.

Subduction: one plate moves underneath the other plate, and then melts, creating volcanoes.


At continental-continental convergent boundaries, ‘folded’ mountains are formed!!

Mt. Everest in the Himalayas (India-China)

Appalachian Mountains (North America-Africa)


3) Transform boundaries

Places where two plates slide past each other side-by-side.

What is orogeny?

Orogeny: the processes that form all mountain ranges

Mountains form at CONVERGENT plate boundaries.

How do mountains form?

Oceanic-oceanic convergence: volcanic “island arc” mountains….islands in the ocean!!!

Oceanic-continental convergence: volcanic mountains AND mountains formed by the uplift of continental crust by the subducted oceanic plate

How do mountains form?

Continental-continental convergence: no subduction occurs during collision of two plates, so rock just folds upward

Earth’s tallest mountains are formed in this way!!

How did the Appalachian Mountains form?

1) North America and Africa collided, forming volcanic mountains in between the continents. These mountains were then pushed over

top of North American, forming the Blue Ridge Mountains

How did the Appalachian Mountains form?

2) Africa and North America continued to collide, causing the rest of the Appalachian Mountains to form.

What other mountain types exist? 1) Divergent boundary mountains

Mid-ocean ridges

2) Nonboundary mountains Uplifted mountains---forced upward from

forces UNDERNEATH them…not from boundary collisions

Fault-block mountains---occur near faults and move due to fault movements

Volcanic peaks

What causes earthquakes?

Forces within the earth cause gigantic vibrations, which are earthquakes!!

These forces are called STRESS and STRAIN.

What are faults?

Fault: fracture of rock that occurs during breakage due to too much stress

What are faults?

Three types of faults:

1) Reverse “pushed together”

2) Normal “pulled apart”

3) Strike-slip “slide past each other”

What are faults?

Normal slide

Reverse overhang

Strike-slip misalignment

What are earthquake waves?

Earthquakes are caused by vibrations….the vibrations are caused by seismic waves!!!

What are earthquake waves?

Three types of waves… 1) Primary (P) waves

Squeeze-and-pull motion 2) Secondary (S) waves

Up-and-down motion 3) Surface waves

Side-to-side motion

Other earthquake terms…

Focus: where an earthquake originates UNDERGROUND!!

Epicenter: the point on the surface of the Earth that is directly above the focus

Other earthquake terms…

What is seismology?

Seismology: the study of earthquake waves

Seismographs: sensitive instruments that detect vibrations within the Earth

How do scientists locate the epicenter of an earthquake? P-waves travel FASTER than S-waves!!

The time between the arrival of the P-wave and the S-wave of an earthquake at a recording station is directly related to HOW FAR AWAY the earthquake is from the station. Big gap between P and S waves- far away Small gap between P and S waves- close

How do scientists locate the epicenter of an earthquake?

Scientists need data from THREE recording stations in order to pinpoint the epicenter of an earthquake.

How do scientists locate the epicenter of an earthquake?

How do scientists measure earthquake strength?

Magnitude: the amount of energy released during an earthquake

Richter scale: most common method of measuring earthquakes Below 2.0…quake is barely noticeable Above 7.0…quake is very destructive


Modified Mercalli scale: measures earthquakes based on the amount of damage the quake causes

I. Not felt V. Felt by everyone. Dishes and windows

break. XII. Damage is total. Objects are thrown

upward into the air.

Where do earthquakes occur?

Most earthquakes occur near plate boundaries!!

80% of all quakes occur in the Ring of Fire! 15% of all quakes occur across southern

Europe and Asia 4% of all quakes occur along mid-ocean

ridges. 1% of all quakes occur randomly (like in

NC)

Where do earthquakes occur?

What factors are related to earthquake damage?

Most deaths during quakes are caused by building collapses.

Stone, concrete, and mud buildings collapse most easily.

Wooden and steel buildings are safest.

What other damage is caused by earthquakes?

Landslides: rock and mud falls down steeply-sloping areas. 30,000 people were killed by landslides in

Peru after a 1978 quake.

Soil liquefaction: vibrations cause soil to turn into ‘quicksand’, which causes houses to collapse or sink into the ground.

What other damage is caused by earthquakes?

Tsunami: large ocean wave generated by vertical shaking of the seafloor 120,000 (or more) people killed in 2004 by

a tsunami caused by an earthquake beneath the Indian Ocean

Who is at risk for an earthquake?

Areas that have had many earthquakes in the past WILL have many earthquakes in the future!!

(21.1) How old is Earth?

Earth is about 4.6 billion years old….that is 4,600 million years!!!

Geologic time scale: Earth’s timeline of history Divided into Eons

Divided into Eras Divided into Periods

Divided into Epochs

How old is Earth?

How is time measured?

Eon (longest): each eon is billions of years

Era: each era is hundreds of millions (to billions) of years

Periods: tens of millions (to hundreds of millions) of years

Epochs (shortest): millions (to tens of millions) of years

(21.2) How do we determine how old rocks are? There are 2 ways to determine the age

of rocks.

1) Relative age dating: comparing one rock to another and determining if it is “older” of “younger” than the other one

2) Absolute age dating: finding the EXACT age of a rock by using radioactive chemicals

What is relative age dating?

The Principle of Uniformitarianism: processes (i.e. the rock cycle) that are occurring today on Earth have been occurring in the same way since Earth formed

The Principle of Original Horizontality: Sedimentary rocks are deposited in horizontal layers


The Principle of Superposition: In an UNDISTURBED rock bed, the oldest rocks are at the bottom, with younger rocks at the top.

The Principle of Cross-Cutting Relationships: An intrusion (dike or sill of magma) or a fault (shift) is YOUNGER than the rock it cuts across.


Unconformity: a rock surface that exhibits erosion (it appears to be rough)

p. 560 Book Quiz

1) Which rock is the oldest in the diagram? 2) An unconformity exists between which two

layers of rock. Explain your answer! 3) What type of material makes up part ‘A’ in

the diagram? 4) Why do the rock layers on the left side not

match up with the rocks on the right? 5) Using ‘A’ through ‘I’ and ‘N’, label the rocks

from OLDEST to YOUNGEST.

(21.3) What is absolute age dating?

Absolute age dating: finding the exact age of an object using radioactive elements Radioactive elements decay from one

chemical to another chemical over time! Carbon-14 Nitrogen-14

The HALF-LIFE of C-14 is 5730 years. # of years that it takes for HALF of C-14 to

decay into N-14.

What is absolute age dating?

% parent % daughter

Years # of half-lives

Time 1 100 0 0 0

Time 2 50 50 5730 1

Time 3 25 75 11560 2

Time 4 12.5 87.5 17090 3

How else can we determine absolute (exact) age?

Dendrochronology: comparing tree rings to past events

How else can we determine absolute (exact) age?

You can tell… Age of tree Condition of environment during each specific

year

Tree rings are far apart lots of growth that year that year must have had a good environment

Tree rings are close together little growth that year must have had a poor environment for growth

How else can we determine absolute (exact) age? Key beds: layers of rock that are known

to have come from a specific time in history and can be used as a time reference.

Example—Mt. St. Helens erupted in 1980 and spewed out ash. This ash settled to the ground to form a “key bed” of ash. We now know that any rock layer BELOW this ash was formed before 1980 and any rock layer ABOVE this ash was formed after 1980.

(21.4) What are fossils?

Fossils: evidence of once-living things

There are many different types of fossils…

1) original preservation: (permineralized fossil) soft and hard parts of an organism have not changed since death Mummified humans

What are fossils?

2) Altered hard parts: all fleshy material is removed, and the hard parts are replaced by minerals. Petrified wood

What are fossils?

3) Index fossil: fossil that can be used from scientists to date a specific layer of rock….the species must have lived for a short time.

4) Mold: hollowed-out impression of a shell, plant, etc.

What are fossils?

5) Cast: hollowed-out impression is filled in with sediment or minerals

6) Trace fossils: indirect evidence of life, such as worm trails, footprints, and “petrified poop” (not an actual organism)

Chapter 22 Overview

Rock samples studied by scientists have been dated (using absolute age dating) at approximately 4.6 billion years old, so that is how old Earth must be!

How did Earth heat up?

3 sources of heat for early Earth…

1) Radioactive elements gave off heat.

2) Impact of asteroids and meteorites caused huge (hot) explosions.

3) Greenhouse effect…”blanket” of air surrounding Earth.

How did Earth’s crust form?

Earth used to be a hot, molten ball!!

Over time, the hot rock (within the mantle) cooled, forming a rocky crust.

Then, the rock cycle began and sedimentary and metamorphic rock joined the igneous rock!

How did Earth’s atmosphere form?

During early Earth, hydrogen and helium dominated the atmosphere.

And… H2O, CO2, Nitrogen gas, carbon monoxide,

and other gases vented from volcanoes

How did oxygen form in Earth’s atmosphere?

Oxygen formed on earth by….

Bacteria (3.5 bybp) used photosynthesis to “breathe” carbon dioxide and release OXYGEN. Slowly, the oxygen levels increased to a point that could support more advanced life.

How did oxygen form in Earth’s atmosphere?

We KNOW that oxygen was present in Earth’s early atmosphere because…

“red beds” of iron oxide (rust) was found in rocks. Iron oxide CAN’T form unless oxygen is

present. These “red” rocks were dated by scientists

to be 3.5 billi² 耀 years old.

How did oceans form on Earth?

Oceans formed on Earth from two water sources.

1) Volcanoes spewed out steam (evaporated water), which later cooled and condensed into liquid water.

2) Comets (balls of ice) crashed into Earth from outer space and melted.

How did life form on Earth?

Miller-Urey experiment: mixed hydrogen, methane, and ammonia to simulate early atmosphere.

Added sparks to simulate lightning. Soon, organic molecules were discovered,

which could have turned into life!!!

How did life form on Earth?

Life likely started in oceans, either in shallow surface waters or on the ocean floor at hydrothermal vents.

(11.1) KNOW YOUR VOCABULARY!!!

It is extremely important to be familiar with… Ozone Troposphere Stratosphere Mesosphere Thermosphere Exosphere

How is heat transferred? 1) Conduction: the transfer of energy through TOUCH STOVETOP IS HOT…PAN IS COLD…PUT PAN ON

STOVE…HEAT MOVES FROM STOVE TO PAN…PAN GETS HOT

2) Convection: the transfer of energy through FLOW (convection current) BOILING WATER…HOT WATER RISES WHILE COOL

WATER SINKS…FORMING A CYCLE…”CONVECTION CURRENT”….WE SEE AS BUBBLES

3) Radiation: the transfer of energy through SPACE FIREPLACE IS HOT…ROOM IS COLD…HEAT TRAVELS

FROM FIREPLACE THROUGH SPACE IN ROOM…ROOM BECOMES HOT

(11.2) What is the difference between temperature and heat?

Temperature: a measurement of how fast the molecules of a material move around “Hot”: molecules move FAST “Cold”: molecules move SLOWLY Measured by F, C, or K

Fahrenheit, Celsius, or Kelvin

What is the difference between temperature and heat?

Heat: the transfer of energy that occurs due to a difference in temperature between two materials Energy flows from on object of higher

temp. to an object of lower temp.

What is wind? What is humidity?

Wind: movement of air caused by temperature/pressure/density differences between two air masses.

Humidity: the amount of water vapor in the air

Relative humidity: when it reaches 100%, it rains…the air can’t hold any more water!

(11.3) How do clouds form?

Clouds form when warm, moist air rises, expands, and cools. Water forms around particles of salt or dust

in the sky to form water droplets.

What are the major types of clouds? Types of clouds… See table 11-3 on p. 287!!!

Combine HEIGHT word and SHAPE word to create cloud name…

Strato = low; Alto = middle; Cirro = high Cirrus = hair; Cumulus = puffy pile;

Stratus = sheet; Nimbus = dark rain cloud

What causes precipitation?

Coalescence: small water droplets combining to form larger droplets that then FALL out of the cloud by the act of gravity

(12.1) What is meteorology?

Meteorology: the study of atmospheric processes and events….”meteor” means high in the air

What is the difference between weather and climate?

Weather: current state of the atmosphere….it changes daily!!!

Climate: long-term variations in weather over a geographic area The angle (and intensity) of sunlight is the

major factor that determines climate More direct at Equator = tropics More indirect at Poles = arctic region

What is an air mass?

Air mass: large body of air that is influenced by the area over which it forms Continental tropical (cT): warm and dry Maritime tropical (mT): warm and humid Continental polar (cP): cold and dry Maritime polar (mP): cold and humid Arctic (A): same as cP, but MUCH colder!!

What is an air mass?

All of these air masses MOVE and INTERACT, which causes WIND, STORMS, and all other WEATHER!!!

(12.2) What are weather systems?

There are many types of weather systems….

1) Permanent wind systems Trade winds Prevailing winds Polar easterlies

What are weather systems?

2) Jet streams: narrow bands of high-altitude, fast-moving winds

3) Fronts: narrow region separating two DIFFERENT air masses Cold fronts: causes clouds, rain Warm fronts: causes clouds, rain Stationary fronts: two fronts collide and

“stall” (P. 308-309)

What are weather systems?

4) Pressure systems: cause pressure changes that allow air to move in a rotating motion

High pressure system: usually good weather

Low pressure system: usually stormy weather

(12.3) Weather Data

Thermometer: measures temperature (a liquid expands when heated and fills up a tube)

Barometer: measures air pressure Pressure drop = future storm!

Weather Data

Anenometer: measures wind speed Hygrometer: measures humidity Ceilometer: measures height of cloud

layers

Weather Data

Radar: radar waves bounce off of large raindrops (but not small droplets within clouds)

Satellite: tracks clouds (but not necessarily rain)

(12.4) How is weather analyzed?

Isobar maps: “topographic maps” for pressure differences The closer together the ‘isobar lines’, the

faster the wind speed!!!

How accurate are weather forecasts? ACCURATE from 1-3 days INACCURATE from 4-7 days (or more)

(13.1) What are thunderstorms? At any point in time, about 2,000

thunderstorms are occurring on Earth!!!

3 conditions are needed for formation… 1) Lots of moisture in lower atmosphere 2) Air must be lifted/cooled so moisture can

condense into liquid water 3) The moist air mass must be unstable so

it can continue to rise (so that the cloud gets big!)

What are thunderstorms?

Air-mass thunderstorms (temperature differences between 2 air masses) Mountain thunderstorms Sea-breeze thunderstorms

Frontal thunderstorms (produced by advancing cold fronts)

What are thunderstorms?

3 stages of a thunderstorm…

1) Cumulus stage: air rises and cools so that moisture condenses into liquid drops

2) Mature stage: precipitation forms and downdrafts/updrafts (winds) form

3) Dissipation stage: winds/energy/ precipitation “run out” and the thunderstorm ends

(13.2) What other weather occurs along with thunderstorms?

Supercells: the most SEVERE thunderstorms with high winds

Lightning: electricity caused by rapid air movement within cumulonimbus clouds 5 times hotter than the sun!!!

What other weather occurs along with thunderstorms? Hail: frozen water droplets that form

within clouds

Floods: occur when storm systems move SLOWLY

Tornadoes: occur when wind speed and direction change suddenly Fujita scale: F1 (least) to F5 (most severe)

(13.3) Tropical Storms

Tropical cyclones: large, rotating, low-pressure storms

Tropical Storms

Steps in tropical storm formation…

1) Warm ocean water evaporates, then condenses to form clouds

2) Low pressure area develops in the middle of clouds

3) Pressure differences cause rotating winds to form

Tropical Storms

Tropical Storms

Saffir-Simpson scale: categorizes hurricanes Category 1 (weak) Category 5 (strong)

Storm Surge: winds drive a mound of ocean water over land

(13.4) Other Weather Events

Droughts: extended periods of well-below-normal rainfall

Heat waves: extended periods of hot weather

Cold waves: extended periods of cold weather Wind-chill factor: takes into account the

effect of winds on temperature

(Ch. 14) What is climate?

Climatology: study of Earth’s climate and factors that influence climate change

Causes of climate… 1) Latitude: sun’s rays are more direct at

the equator and less direct at the poles 2) Water/mountain effects

Coastal areas are more mild year-round; mountain areas are usually cooler

3) Air masses: mT, cT, mP, cP, A

What is climate?

Koeppen classification system: way of classifying climates using temperature and precipitation

What is climate?

Microclimate: localized climate that is different from the overall regional climate Mountaintops, cities, etc.

Heat island: presence of concrete buildings/blacktop increased temperature

What is climate?

Climates CHANGE over time!!!

Ice ages Seasons (every year) El Nino: warm ocean current off South

America that affects worldwide weather Solar (sun) activity Volcanic activity

What is climate?

Climate can be changed by HUMANS… (“An Inconvenient Truth”)

(9.1) How does water move on Earth?

On Earth, water is transported throughout the WATER CYCLE.

Evaporation: liquid to gas Condensation: gas to liquid Precipitation: liquid falling from

atmosphere to ground

What is the water cycle?

Runoff: water falls to surface, and runs ALONG surface into larger body of water

Seepage: water falls to surface, then soaks into the ground into groundwater

Transpiration: evaporation through plant leaves

What determines whether water will seep into the ground or become runoff? 4 conditions determine whether seepage

or runoff will occur…

1) Vegetation: more plants/grasses = more seepage; less plants/grasses = more runoff

2) Rate of precipitation: light rain = more seepage; heavy rain = more runoff

What determines whether water will seep into the ground or become runoff? 3) Soil composition: coarse-particle soil

(sand) = more seepage; fine-particle soil (clay) = more runoff

4) Slope: flat ground = more seepage; steeply-sloped ground = more runoff

What are streams?

Stream: body of water that flows downslope to lower elevation Rivers, creeks, brooks

What are stream systems?

Watershed: all land area whose water drains into a single stream system

Divide: high land area that separates one watershed from another

What is a stream load?

Stream load: all materials carried within a stream

Living: bacteria, algae, plants, fish, snails Non-living: sediments, gases, minerals


There are 3 ways in which a stream can carry its load…

1) Solution: material is totally dissolved in stream water


2) Suspension: material is not dissolved, but is small and light enough to be carried with the water current

3) Bed load: sediment that is too large to be carried with current, but is rolled or dragged along stream bottom Pebbles, boulders, etc.

What is stream discharge?

Discharge: the volume of stream water that flows over a specific location during a period of time

Discharge = width x depth x velocity

Mississippi River has largest stream discharge in the U.S.

What is a flood?

Flood: occurs when water spills over the sides of a stream’s banks onto nearby land

Floodplain: broad, flat area that extends out from a stream’s bank and is covered by water during flooding

(9.2) How do streams behave?

As a stream develops, it changes in shape, width, and size. It also changes the landscape over which it

flows. Creates valleys, etc.

How do streams behave?

Streams form at the “headwaters”, usually at a high elevation.

Over time, a stream carves a stream channel. Stream channel: a narrow pathway in

sediment or rock in which water flows.


A stream is held within the confines of its channel by the stream banks.

Stream banks: ground bordering a stream on each side.


At first, a stream erodes a V-shaped valley until it reaches its base level, where it will then join another body of water. Straight, narrow

As streams get larger, they form wider U-shaped valleys. Meandering (bendy or curvy)


Sometimes, OXBOW LAKES are formed when a stream blocks off its original path.


As the slope of a stream decreases, its velocity decreases, and its ability to carry sediment also decreases. This usually happens when streams “dead

end” into a large body of water.

Delta: triangular deposit that forms where a stream enters a large body of water

(9.3) What is a lake?

Lake: a depression within the surface materials of a landscape that COLLECTS and HOLDS water

Lakes are always changing… Over time, lakes usually fill in with

sediment until they no longer exist!

What is eutrophication?

Eutrophication: process by which lakes become rich in nutrients, resulting in the change of species “residents” over time

Lake nutrients: nitrogen, phosphorus, animal waste, factory toxins

What is a wetland?

Wetland: land area that is covered by water for most of the year

Bogs, marshes, swamps

Bog: receive water only from rain Marsh: form along deltas and near

oceans/sounds Swamp: low-lying areas near streams

(10.1) What is the hydrosphere?

Hydrosphere: all of Earth’s water 97% of hydrosphere is in oceans 3% is freshwater

Most freshwater is in ice caps! 0.31% of total water is GROUNDWATER 0.091% of total water is in lakes/streams

So….groundwater IS important. We need it to survive!

How do groundwater deposits form?

Most precipitation undergoes seepage…only a small % runs off.

So, most water undergoes INFILTRATION (seeps into the ground) and becomes groundwater!!

This water infiltrates the ground through pores, or spaces, within Earth’s surface.

How do groundwater deposits form? Porosity: the amount of pores within a

material.

Groundwater is stored within the pore spaces that are in surface/underground materials!

The depth underground when water fills ALL of the pores of a material is called the ZONE OF SATURATION.


The WATER TABLE is the upper boundary of the zone of saturation.


The ZONE OF AERATION is the area above the water table, where rock/soil pores contain mostly AIR instead of WATER.

What are rules of the water table?

Water tables are usually…

1) Close to the surface along streams, lakes and swamps.

2) Far from the surface in deserts and mountainous/hilly areas.

3) Dependent upon rainfall…tables rise during rainy periods and fall during droughts.

How does groundwater behave?

Groundwater usually flows downhill and moves through rocks/soils with HIGH PERMEABILITY. Permeability: ability of a material to let

water pass through Large pores = high permeability Small pores = low permeability


Aquifers: permeable rock/soil layers in which groundwater flow takes place.

(10.2) How does groundwater conduct erosion?

Most rainwater is slightly acidic, because the water mixes with carbon dioxide to form CARBONIC ACID.

This acid can “burn” or “eat” through underground rocks to form caves, sinkholes, etc.

How does groundwater conduct erosion?

Cave: natural underground opening with a connection to Earth’s surface

Forms when carbonic acid (in water) dissolves limestone (which is soft).

Mammoth Cave (Kentucky) Carlsbad Caverns (New Mexico)

How does groundwater conduct erosion?

Sinkhole: “crater” usually caused by the collapse of a small cave

What else is in groundwater?

There are many materials dissolved in groundwater.

Sulfur Calcium, Magnesium, Iron (“hard water”)

Calcium Carbonate Slalactites (ceiling) and Stalagmites (floor)

(10.3) How does groundwater behave?

Most groundwater STAYS underground for 100-300 years!!!

Throughout this time, it is found in SPRINGS, AQUIFERS, CAVES, and WELLS before it returns to the surface.


Spring: location where an aquifer meets Earth’s surface and groundwater is discharged.

How does groundwater behave? The water temperature of most springs is

near the average yearly air temperature at that location.

Exceptions…

Hot springs: water is hotter than the human body (98.6 degrees)

Geysers: explosive hot springs Old Faithful


Wells: holes dug or drilled deep into the ground to reach a reservoir of groundwater

What threatens our water supply? Threats to our water supply include…

Overuse Pollution

Sewage Factory Waste Landfills Agricultural Products

Chemicals and Salt Radon (radioactive)

(15.1) What is oceanography?

Oceanography: the scientific study of Earth’s oceans

The ocean is studied using computer imaging, sonar, submarines, etc.

How did oceans form on Earth?

Earth’s water likely came from 2 sources

1) Icy comets and meteors from outer space (hit Earth and melt into water)

2) Volcanic eruptions Steam from volcanoes cooled and

condensed into liquid water

What are oceans?

97% of Earth’s water is saltwater in oceans, seas, and gulfs

Sea level: level of the oceans’ surfaces Rises and falls as ice melts and refreezes Currently rising ~1-2mm per year

What are oceans?

About 71% of Earth’s surface is covered by oceans

ALL oceans are connected Major oceans are… 1) Atlantic 2) Pacific (largest) 3) Indian

4) Arctic Ocean (north pole) 5) Antarctic Ocean (south pole)

What are seas?

Sea: smaller than oceans, contains saltwater, partly or mostly surrounded by land Mediterranean Sea Black Sea Caribbean Sea

(15.2) What is saltwater?

Natural saltwater = 96.5% water and 3.5% dissolved salts (mostly NaCl)

Salinity: measure of dissolved salts in seawater Lower salinities in rainy, tropical areas

More water to dissolve salts Higher salinities in dry areas

More evaporation of water

Where does sea salt come from?

Sea salt comes from…

Volcanic gases Rocks in Earth’s crust Minerals in Earth’s crust

Sea creatures REMOVE salt from the water to make their shells, bones, and teeth!

What is saltwater?

Saltwater is more dense (thicker) than freshwater.

Saltwater has a lower freezing point than freshwater. It needs to be COLDER than 32 degrees

for saltwater to freeze.

What are the layers of the ocean?

Layers of the ocean include…

1) Surface layer: relatively warm and filled with sunlight

2) Thermocline: transition from warm to cold

3) Bottom layer: very cold and dark

(15.3) How does the ocean move?

Wave: rhythmic movement that carries energy through space or matter (in this case, ocean water)

What is a wave?

Crest: highest point of a wave Trough: lowest point of a wave

Wave height: up-and-down distance between crest and trough

Wavelength: side-to-side distance between crest and crest (or trough and trough)

What is a wave?

A large amount of water, high winds, and winds blowing for a long period of time are the perfect recipe for BIG waves.

Waves “break” near shore because they lose their energy…they are ‘grinding’ against the shallow ocean bottom!! Breaker: a collapsing wave

What are tides?

Tide: periodic rise and fall of sea level Daily tide cycles normally take 24hrs & 50

mins

Semidiurnal tides: two high tides per day Mixed tides: one ‘big’ high tide and one

‘small’ high tide per day Diurnal tides: one high tide per day

What causes tides?

The attraction of gravity between the sun, the moon, and Earth causes tides…gravity “pulls” water in, then it “pulls” the water back out!

What are ocean currents?

Current: movement of water within an ocean (a ‘river’ within the ocean)

Gyres: circular currents

Upwelling: vertical (upward) motion of water Cold bottom layer water moves towards

the surface

(16.1) What are some features of the shoreline? A lot of erosion occurs at ocean

shorelines…the energy from the crashing waves breaks down rocks.

As a beach is worn down, many types of rock formations may form. Cliff Sea stack (isolated rock towers) Sea arches

What are some features of the shoreline?

Beach: sloping band of sand, pebbles, gravel, or mud at the edge of the sea

What are some features of the shoreline?

The type of coastline that exists depends on the type of source material Rocky coastline = hard rocks White, sandy coastline = quartz, etc. Black, sandy coastline = volcanic rocks Muddy coastline = sediment from nearby

rivers

What are estuaries?

Estuary: area where a freshwater stream meets the ocean Saltwater/freshwater mix

What type of currents occur near the shoreline?

2 major types of currents occur near shore…

1) Longshore current: current flowing parallel to shore

2) Rip current: current flowing out from shore (towards ocean) caused by a gap in a sand bar

Be familiar with the other shoreline features on p. 417 (Figure 16-7)!!!

(16.2) What are the major features of the seafloor? Using Section 16.2, draw a map of the seafloor.

Include ALL of the following: Continental shelf Continental slope Continental rise Abyssal plain Mid-ocean ridge Hydrothermal vent Seamount Deep-sea trench

(25.1) What are resources?

Natural resources: items that can be used by living things that are provided by the Earth Air Water Land Animals/Plants Nutrients & Minerals

What are resources?

Renewable resources: resources that can be used (forever), without causing a decrease in the supply Trees Crops Livestock Sunlight

What are resources?

Nonrenewable resources: resources that exist in a fixed amount and CANNOT be replaced in a short amount of time Diamonds Oil

RENEWABLE RESOURCES CAN BECOME NONRENEWABLE IF HUMANS ARE NOT RESPONSIBLE WITH THEM!!!

Who uses natural resources?

Natural resources are NOT distributed evenly across Earth…countries that have MORE natural resources are usually MORE SUCCESSFUL U.S.: Iron, Coal, Oil Russia: Minerals Saudi Arabia/Kuwait: Oil (LOTS!!!)

Who uses natural resources?

The U.S. uses ~30% of the Earth’s natural resources every year, even though the U.S. only has ~6% of Earth’s human population!

(25.2) Land Resources

“Public Land” in the U.S. is protected in order to preserve plants, animals, soil, and minerals. 42% of all land in the U.S. is protected

“public land” BUT…only 5% of this protected land is in

the eastern U.S. Most protected land is in Alaska/Western

U.S.

Land Resources

Land resources include…

1) TOPSOIL It takes 1000 years to form 1-2 inches of

rich topsoil Erosion and desertification (cropland

becomes desert) are becoming problems resulting in fewer crops (food) being grown

Land Resources

2) ROCK Limestone, granite, marble mined and

used for buildings, flooring, etc. 3) AGGREGATE

Mix of sand, stone, and pebbles used for concrete and gravel.

4) ORE Rocks containing metals

Iron (for steel)!!!

Land Resources

5) MINERALS Salt, graphite, diamonds, etc.

(25.3) Air Resources

Air is needed to be kept clean so that the CO2 Oxygen cycle is not disrupted!!

Air Pollution Natural Sources

Smoke, gases, dust Human Sources

Burning of coal, oil, gas, etc. (fossil fuels) Car exhaust = #1 source of pollution!!!

(25.4) Water Resources

Only ~0.003% of Earth’s total water supply is available for human use (all other water is either salty, too far underground to use, or frozen)

Water is NEEDED for farming, transportation, and for human life…65% of our weight is water!!!

Water Resources

25 countries (mostly in Africa) experience droughts almost every year, and by the year 2025, more than 90 countries will experience droughts.

Desalination: the process of removing salt from ocean water

(26.1) Energy Resources

Solar (sun) energy is the original source for ALL energy on Earth!! 1) Plants capture sun’s energy 2) Animals eat plants stored energy is

transferred to animals 3) Plants that die before being eaten by

animals fossil fuels (oil, coal, etc.)

Energy Resources

Traditional Energy Resources 1) Wood 2) Field Crops (burned when wood is

unavailable) 3) Animal Poop (burned in poor countries) 4) Peat (rotten bricks of moss; used in

Northern Europe) 5) Fossil Fuels (coal, oil, gas)

(26.2) Alternative Energy Resources Alternative Energy Resources

1) Solar energy Solar heating, solar cookers, solar batteries

2) Water energy (Hydroelectric Power) Dams…moving water turned TURBINES

3) Geothermal energy (Earth’s inner heat) 4) Wind energy (giant windmills) 5) Nuclear energy (efficient but dangerous) 6) Alternative Fuels

Ethanol, Biodiesel, Methanol

(26.3) How do we conserve energy resources?

In order to conserve Earth’s resources, we MUST…

1) Make energy more EFFICIENT Use resources in ways that are most

productive and least wasteful 2) Use more renewable resources (by

using alternative energy sources) Hydroelectric, wind, solar, ethanol, etc.

How do we conserve energy resources?

Energy efficiency can be improved by…

1) Recycle old appliances & vehicles and buy newer, more energy-efficient ones

2) Install solar panels on homes 3) Governments offer $$$ to people who

conserve energy 4) Use fluorescent lightbulbs in your house

(Saves ~$100 per year in electric costs!!!)

How do we conserve energy resources?

5) Use public transportation (buses, trains) 6) Use SUSTAINABLE ENERGY practices

Manage resource use to meet human needs without causing environmental damage.

What is Earth Science? Earth science: The study of ‘Earth Systems’. Astronomy: The study of...

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