!

IIIi

. :: .r...,,,-r n r\ ! ! :, *i.l\ tI > ir fd{lut i' ': :

!ti-I1 /!l" i\ r l-

Minerals:l"

1. naturallY occurrtng

2. homogenuous,solid :

3. cornPositicna. chenric':'l (clefinite but.generally not fixed)

b. PtrYsica4, orderecl aiorni.c ?fl'?rrlerl€flts. .trtrrrt f :'rme'l oy ill(lrganic prrrcersses

Mi neral oi rls - natttri:liy occurri n g 4]1ryThgf sr"tbstances

*Tire orderly p.arterns ihat

crystallin u- stru cture

ffq'NERALS

witrtout crYstalline structure

aton:s of elements assume in a rr''ineral is called iis

* Polymorplrs r ntinerals lra"ing the

crystalli;',e struc:t r]'es I

examPles:

same composition/elernents br-rt different

-* Pvt'tqano ir.-arcasite . -;

-- -l -^^^nrla I- Calcite atrd -.-,ragonite .---__ I

*Alias es:1. Caiclte - islan'l sPa;

2. FYrite - 1os1'1i cl'rld

3. Quart;. - ice cnilstals

Georgius t\gr:cola (Georg Bar'rer) D",f.q Metallica- , ..,,,,' ,,, , ,i, ,, . ,

Optical Fic';:e*ies;

2- dotrble refrtl;tion

':---

fff:1":',oJ11J':1,. rrerar oytlrald unngu*rg"3,; consists rr a sroup oi' crvstai

t,,,,"r, Tii';i':*n'.f,-nuuu the same relation to the'"j"ll::::,^oj' ,-th* same chemical an* physical properttes

s':rintlettv ancl cltsPti'

because ;:[l are ui ;.erlain bY

af'ang€'Tlentex. pr,smatic

cubic '

*Nicolas steno - pointed out that the angles between correspo.nding faces on

"rfttuft of a nrine:tai [quartz] are always the same

* Rome de I'Lsle

*Law of consta*cy of Interfacial Angles - angles between equivalent faces of

crystals of the .ru"l* substance, measured at the same temperature are

constant.

2. crystal habit - e.iternal shaPe

ex. botrYoidar, iihrous, grar"uiar

3: color - i': ti:e brightr'.ess or Carl"ness of a mineral :r-,- -^-.-{-r'.._. - resurl of ilie ieflection of light within the visible spe -trum

a. idroch,om:tic - ex. rruscovite (white or c.olorless), azurite (azure blue),

' rnalachite (green): sulfur (yellow)

b'. allochr:matic - ex' quartz

4. streak' is the color qiven by a pulverized mineral

eX'a.hernatite:streak=reddish.brown/indianred| : color = red to black

b lir'ronite : streak = Yq'llow: color = bl''-,wn

5. luster - qual:':, 3nd intensity of right that is reflected frcm I re surface of a

lnir,eral- can be lrouPed into: 'r

a metailic - luster "rf untarnished rnetal; the usual characteristic' of

Iike atoms in the same geom€

I

dark and opaque rnineralsex. nylite, golcl

h. non-metallic - ir,utatl"rizes the colored nrir erals , , l :,

, b. i resit'rous - appearance of resin .

b.; vitrer-rus - glass

u.s ouiil"urt'i:b.4 adamantiire - diamondb.5 silkY - silklikeb.i pearly - iridescent pearl-like lusJer..,

u.z 'grenJv

-rpp"ars to be covered wiil. thin layer of oil

!

i

I

I

I

I

I

x&

A*

6. lrarciness - abiliiy of a rninerill to-withstand abrasion or scratching- in .licated in ternrs of the Mohs' Scale of Hardness

q

114-r5 diamond hardest

Practical scale:

r;, specific

ex.:

gravity. - refers to the ratio of the weight of a volumeof material tothe weight of an eclual volume of waier

- spr:ing scale; hefting the mineral by hand

| 2.65 feld 2.56-2.76old

c. boti a and b

19.3

q. cleavage -,i:iers to the characteristic tendency.of mat,minerals tc spiii. c:'

sepa:'ate easily along certain planes- govenred by interrial arrangement_ weak,:lssl

a. .ype of brr cring \b. greater alomic sPacing

rfectvery good at 9C degrees to each other'

fair at 90 dectrees I9,n9-.--.--iat 56.dsgleeg !r 124 degree.- amohibole

e

Perleei-oei-ellA Oegrees; rhombohperfect _ diamond

calcitefluorite

CLr-coin

feldspar

'r nerft':ctv 'F

sphalarite

g. fracture - refers to the nature.of ir''" surr"ce formed by the ''rreaking in the:

oir""i'"n other than those of the cleavage

' -i-\a' cort:hcidal (ex' quartz)

b ri;'i;;;i'itint"'Yc' hai;'liY' d' irregu'ar

- ^r ^r'"^{rrral rnta: ruintiing or-

l0.parting-breakingalongp|anesofstructuralweakness;resultofttpressure

ll.tenacity-resistarcethatamiiteralofferstobreaking'crushing'bendirig'tei ring

a. brittle - breaks or powders eas.ilY ,

n' tnuiiuuble - hammered into thin sheets

c. sectile - can be cut'into thin shavings with a knife

' cl' 'Cttctile - drawn into wire

". ;;ilL - n*nos but does not return to origina' shape

nr

12.

4'I

14.

', 5.

16.

1'l .

f. elastic

fluorescence' artd phosphoresceneet.

magnetism

reaction to HCI

taste

srnell

striations

. CI.ASSIFICATION OF MINERALIE.I-CCORDING TO CHEMICAL GROUPS

native elements old, sulfur, diamondoxides maqnetite, hematitesulfides rite, qalenasulfatescarbonates calcite. dolomite

apatite

EIGHT MOST ABUNDANT ELEMENTSIN THE EARTH'S CRUST

27.72B.135X0

silica Tetrahedron . basic burlding block of the earth's crust

*polyrnerization

Silicates - most abunCant mineral group r

Feldspars - rnost abundant mineral

(bl Silicon.Oxygen Tctraledron cxpandcd

3.632.832.59

hclsphatessilicates uartz, feld l-

(rl Teuahcdron

(d) Top view

Silicate Structures

orthosilcate ornesosilicatesorosilicate

cyclosilicate

irrosilicate

phyllosilicate' (si2o5)-

lectosilicate

'1. quarlz2. feldspars3. nephelilg4. sodalite5. leucite

epidote, hemimorphite

beryl ,

roxenedouble chain SjaOrr amphibole

sheet silicatequartz, feldspar

framework

t

COMMO}{ ROCK-FORMING MI NERALS

6. mica

amphibole9. olivine

(sio4)independent SiOq grou

(Si2Oz)lir.king of 2 SiO4(si6o16):rinq silicateschain silicates

sinqle chain (Si

II

,l'Definitions:

. -*.. cfrnred, r:onsolidatedirlocirs - r1:ltursuv ::il;;i.;;r, glass oroiganic ttiatter, rocx

4.1 lGNDOus R(Juri"u '

t ^r mrnerals'niaterials whiclr maybe conposeo ut

a cornbination of these' l

Iglteorts roclcs:fLatin "ig7lf$" fire) - fgrrned by direct

nlilgttt' Magntu

crystaUiztrtion and solidification of

- "l{llr,acled nrixttrrd'

E l,s gi il ile;tuilssleri$ii- rnol:ih

-'1,:, t*.,?f,

,lTilo",',u*d r:l:?:51 tlissslvecl sases ' : or in rhe upper rnantle due to

' forr:retl n' o "*uti

Jtltrtr partial *ati'ie ii 't'qti'wer cnist or in the upPer rnar

- ' ';;i;;,';'ic iieat,anrl/ot decreasT:.[:Tlfapped lruithrn

the earth's cnrst

-;.;,i;;'l.placecl on tho earth's surla(

-;;,;;n.,,. cltnmbers

*,*;r{:L::::f;j::,t',# l,"f,f'Na' K,'

-r ^:- S(Oi - PnllclPat- <rjssalvecr gases ;;;ii;:;riiu,*",r uirlo*tv and explosive characteristics

- rilnfie ',f t"nt1t"*tit"J' 6i]0'- 1200'C

- ,]"rir, L'I20-,:aPor, COr, SOz

- Xlrvn

Lli.'ir.r-,j:,Pggn. tltsnltic Inagmfl

l"t. Grnnitic nraEitna

" 50% Si0z. 't:900-12C0"C

highlY fluid

eolr6Y, sloa

' T: lower than B00oC

- highlY viscous

l.Ld.tiri,--nn{erysldliag'lstr . -c^L^ni:'.i.aciion $eries = '-o;j-"'tiy series of change"

J- ' ,1".',-tts Reactiorr Series .,i. ,

.," r in whish the'earlier fornred inrler$s

:; n ll; t' -*:i'iil1: :, : Tf i;' :'il:r:'; il; ';;'i #'oi;"' r'm "''t i' trre

, tt,rti.*. in the mineral

is graduallY

rnrgma'fbr

ex.: plagioclase (Ca-rich torl(rich)f.)iscontinuous Reaction Series : reactiorr in which an early crystallized mineral reacts

with the remaining licluid which constantly. changes its conrposition during cooling to form

ancther mineral

ex.. 'ii,,,, Enstatite + Forsterite + Melt

2 Mg SiOr MgzSiOa SiOz

Magmatic ;lifferentiation : a general piocess in which the original magma with its full

.ung. of cornponent elements is separated into rocks of different mineral composition

a. fractionation

b, filter o:essing. c. assimilation of the wall rock

d. magnra-mixing

Morlqresl-af.tnsglqaa. external.forces - sqrteezing of rnagma chamber and causs filter pressing

b. internal forees - gur **punsion; stoping (magma move along fractures until they engulf

the ho$ rock)

tgnerrus rocks ,

- 80% of the mass of the earth's crust

- Genetically classified intorr''| a. plutonio: intrusivb

li, volcanie = extrusive Ic. liypabyssal

- Mineralo$ically:a, felsic - large proportions of K-feldspar and Na-plagiocl456 + quartz

b. mafic - Ca-plagioclase, large hmounts of{endrnagnesian mlrerals but littlequartz or K-feldspar

c. ultramafic - composed entirely offerromagnesiatt rninerals with minor amounts

- Major textures of feldsPars

Textirre Dcscription Inte'rpretationPhaneritic grains visible to the

naked eve

relatively slow cooling

Aphanitic grains not visible tothe naked eye _ _

relatively fast cooling

Forphyritic some grans coarse,

others line(phenocryst,

sioundmass/matrix)

two cooling rates

no minerals fonledr id s"tft; co4llg witElgSie eg

9X

Most Abundant lgneous Rocks

s.trapes brrfiirtiilve rock bcdies

" Flutoir ='any llass of intntsive rrrck regardless of its size or shape

a. batholithsb. :tcsksc, dikesd. sillse. lacolithf. tupolith

imflb rlancb:' r.retaliic and

' ' : -"L. :- i' (' '

\ro!r:n:iowith the

I

non-metallic minerals (mining): gold district

5.1 Yolungoes ''

!-

: a vdni which connects a reservciir of maguu in the deptlis of tlie earlh's crust

surface of the earth: ejc"ts lava, fragmentaVpyrociastic rocks and gases

: cons (volcanic edifice)

A. Lavanffiu that h1S reached the surface of the earth

- different compositions ancl temperatures iesulted into lavas with a rango of physical

properry (i.e., r'iscosity) and fcafules.

a.. paloeho* riua -:t:glly fluid, T = 1000"c; thin; smooth, biilciwy, ropy suilace

b. aa l.vr - fi'-il; "ibtlu$;

iini.'guq $low moving; seu*rh neters thick;rough'

':' jugg*d, sPinose

c. pittorv-,ta.iu1"-Iffii;pted under water or ice; (toothpaste-like) '

#-

Extrusivefeiric r" ck[ K.ftiltdMptfiioclase, qtr arte, less

amountp of biotite or ampbibqle-. -. .

ffie(30-50% anorthite),

a,rnphibole,, gqoi*. (quartz may be present in

Intrusive

Granite Rhyolite

Diorite'Andesite

amounts of olivine"t'Gali,bro- ' Basalt

I .f

a ,l ll. F!'rqginstic materials

-:il:,:m#*'ffffiT$rrue**,s blown-out from a volcanic vent under pressure or

raoidlv expanding gases present in the magma

- rr*tpoi.d eitfiei+n in solid or plsstic state

- classification in telTns of sizes and shapes of the fragments r -a, blocks - > 64 mm; pieces of crustal layers or older lavas

b. bombs - > i4mm; spindle/spherical masses from the congealing of blebs tllj:d

Iava

" b"l bowdung

' i b'z breadcrustb'3 armored

,0 c. lapilli -2-64 mrn; saccretionary lapilli

4 ash-<2mm

+*r- Pu,nice, scori&, obsidian (volcanic glass)

..'j:a

T:

.;, ..:,ts, domppsite/strntevolcnnoes: altemntingla-yers of pyroclastic rocks and lava

ex.. Mt. ttu.ii, V.r,,nius, Stromboli' Etnq Mayon' Mont Pelpt'Krakatau

' nuee srdente (glowine cloud) : a higtrly hh?{ gas 'charged with incandescent

i ,rt porti"ie, ,oitrut i, i"g"*ii*r u *ouile ernulsio--n ydtidense enough to maintain

lntact with surface '

r.ldera - co.llapsed volcano (ex' Taaf,Laguna Bay)

.;r .:ir

b. Shield ".olcailoes - broad, gently sloping.v-;rcantjes comPo$ed of solidified lava flows;

rarelY stePPer than,f:dtigrees '

ex. Mauna Loa': '

, a

'il. Cindur cones - volcano that is constructed of loose fragmentilpyroclastics;slopes

about 30-33 degrees

ex. Parictrtin

- PACTF'IC RING.OF FIRE/CIRCIJM-PACTTTC BELT

Type of Volcanic Eruptions: -rr --^,.-|.^.rri.onh,erl .,cq.eq*. influencealfnir"ority of the magma aitd a{nourlf oi dissolved gases

- .\iolencs" "'r.n

,*pii* i, ,rtuit io ,rr" o*gree of fragmentation and the \

distance

a. Fflaw*iian - ubundant outpouring of lava flows; lava fountains; quiet liberation of gases

b. Stnoxnholinn - milil, explosive eruption of pasty, incandescent bombs and scoria

ql, accompanied by a white vapor cloud; discrete explosions

- c. vutrcaninn - btsw-out of solidified cnrsts (over the crater); acbompanied by a great-

;;;iifl.wei shaped eruption cloud containing an abundanco of ash; lava'flows may

issue

d. Flininn - eruption of extrerne violence; gas-blast eruption; eruption cloud resembles an

Italian stone pinetree (shooting upward of the column then spreading out); huge'

sustained eruPtion column

Felean - extreme explosiveness; nuee ardente

Phneatic'

F.trreatomagmntic l

Uliru-Ptiniatr - excessive emission of ash resulting to negative landformslLE

g

h.

n*Vqlpgnlg-Hazards (

a. ieplua fallb. pyroclastic fhll

lrnportnnt: geothermal energY

c. lava flowsd. lahars

(ex. Makban, Bacman, Tiwi)

e.

f.caldera collapse

tsunami

s[rMM3'nY

lava fottntains

ffiffi

.. j,::,r. i.:r:.il..l_,'1

:,t,il,i

i+:ir:ri,'i.i;i

!Ii:r;';i'?.ii:li','

!

I

i

I

b9&o'ir 5L)-rr#6p

iiii-ig' btj;iElni.i.'i1.1 Z .E Y

iili$[

6

0,

(sE

E'z

I {}::rl'i':i;l:i+.i

::: olii:i .E r,

l:..ir. 'itr.'..:+i

0)o .c.

6@-rao

o=do)

'7q

LY:t

!i:t

,i iii

wil,AT'r{rcntruc nivn ER,osnoN

iVE,:X'I.!!Eit,lNi- is the physical disintegtation arfci r,hernical decontposition by ivhich

rocks iire changed upon exposure to "agents" at or near the earth's surface, with little orno lranspo;t of loosened or altercd Inateriai

*- agents - hydrosllhere, a-tmosphere, biospher-e

.4. l\4cch*nical Weathering - is the breakdown. of rccks into smaller fiagnents by

vat'ious ph1151"'1 stresses

- ::tictly a lthysicul pl'oces:; willxnt a change in chemicalc1tilP)r'iliott

fr4 erhilnicaN Weath ering Frocesscs

a. ice wedging/ttost wedgingb. salt crystal gror,vth

L:. slrceting/unloading - releasc of confining p:ressure

exfoliation - fonnation of cprved sheets of rock by release of pressure

d. anirnals and plants

e. tlrermal expansion and contraction - seasonal/daiiy temperature changes

tr]. Chenrical Wcattering'- is the process"by rvhich chenrical reactions transform rocks

and nrinerals into ne;, shemicat cornbinations that are stable under conditions prevaillng at

or near the earth"s sur{-ace

lioie: more ef-fectittc itt x'armer clintcle:i - lrcat increase,s tlw xtte of ma:;t

reucf irnts

Chcnricnl Wcatherinq Proccsses

a. Flydrolysis - H' or Otf of the water anAffinUe ions of the rninerals

Ex. I(-ibldspar

2l(Alsi?o8 + 2tt2co3 -F 9FI20

Ortlroclase Carbonic Acid Water

Al2iii205(ot-t),r -l- 4l-I4sio4 J- ?tc + 2{-ICo3'Kaolinite Silicic Acid Potassium Ion Bicarbondte l.on

{, :--*ffi

l). ulSSOllltl0n - Fr2U

Ex.b.l NaClb.2 FITO

CaCOr

. ,1;'

-- --Llnlversat solvent

T

T

HzO -,----+

Na -F

COz HzCOrFizCOr ------+ Caun F

1- FLO

2HCO:-

c. Oxidation *

Ex.2FeSz

4Fe'*

is the cornbiration of oxygen ioris ivith cations

gl&qlar dalrygolbstlqg or "onion-skin weathering" -- produces

relat ively untveathertd material

4SOt' + 4F-t+

2H?O

spheroidal boulders

X{.esults/f roducts:a. regolirlr - fragincntal and uncor.rsoiidated rocl< material that has coarse grains

rvith angular edges and a composition sinrilar to the unweathered rock

" b. very large increase in the surface area of the v/eathered rnatedal, f,,. soluble rnaterials

Xlilr:tons afT'ccting the nntes o{' weathering:

I. susceplibility ot'the consl-ituertt roirrurals to rveatltering

- Goldich Stability Series-- nrinerals forrned at liigher temperatures and pressures tend to be less stable in

uveathering environment than those formed at lower temperatures

2. climale or intensity of the weathering processes

-- total amount of precipitation

- intensity ol'rain-- sr:asonal variations-- infiltration -r

-- run-ofl'and rate of evaporation-- teulperature

''r'wnnn, hunrirlclimate Vs. coid clirnaLe

-J. amount ol'srrrface exposecl to the atmosphefe

f,i?0$'/Ory - forcehrl physical removal of material frorn ihe parent rock, alwa.gs

acconrparried by transportat.ion and eventually end in deposition

CI

+ 7O:r +-t- oz {-

zHzO F 2Fe'-' +4# -_| 4FErr'r +

of

a. running vraterb. grouncl waterc. glaciers

d. 'ivind€.'waves' ald currents

f- mass wasting:' :

g. oigarric activi\'

'" n Dcpositio n itrtti [ix.hit'icatiorl :

I

Il--

Lithifliq:ation - is the term for p group

sedirlen.rarr/ rocksof processes tlrat conrreft loose sediments into

u. C1:me6talion - the process by which sediments are convefted ilt<i roclr by the

cliemical precipiiation of rnineral material / cqment among the grains of the

sediment I

+

t{t-, .

silic.r, carbonates and irolt oxides

Ccrnpactittn = is tlie loss in over-allvolunie and pore space as sedinrent

particles are packed closer together by the weiglt of, overlying rnaterial

Cry:;tallization - refers to crystal developmelit and growth by precipitation

fi'om solution; no cement; grains are held together by inierloclcing crystals

Ser{inrept:ltion - tlre process of fornring sedinqnt in layers, including ttre separation

rocli partioles fit'lnr the palerrt Inaterial, transportation of these pa.rticles to the site

deposirir:n, actual cleposition/setiiing, litlrification and consolidaticn into rock,

oio.l

'\.

SEDIMEhITARY ROCKS

SedimentarY Rocks:

- Latin woi-d, sedimentum = "settling"

- formed from consolidation of materialsprecipitation and from secretion of organisms'

Sediments - finely divided matter consisting of mineral grains and organic

matter derived from pre-existing rocks and from life processes,.transported by

and deposited from alr, water or ice'

- origin:

(1) weathering and erosion of pre-existing rocks

izi cnemical prebipitation from solution(3) secretion of organisms

Ocean = ultimate destination

Partlcie size classification for sediments

Two Maior Textures of Sedimentary Rocks.

1. clastic [Greek k/asfos, "broken"] = discrete fragments and particles

2. non-clastic texture = minerals forming an interlocking crystal pattern' '

from pre-existing rocks, from

.

CommonSedimenf Narne

Gravelor

Rubble

[dden-WentworthSize Glass .

Particle Name

1116-21/256-1/16

Iypes of Sedlrrient'ary Kocr(s

a. Detrital sedimentary rocks'.particle size is the primary basis

Detrital RockUOOenlWentworth

Size Class(Particle Namq)-

CommonSediment

NameConglomerate

UI

Breccia

Boulder Gravel

RubbleCobblePebbleGranule

SandstoneSand Sand

sitt Mud siltstone Shale or mUdstone

Clay clavstone

b. chemical sedimentary rocks: formed by direct precipitation of minerals

from solution.

*Precipitation occurs in two.ways:

(1)lnorganicprocessessuchasevaporationandchemica|actirTity can produce chemical sediments'

- iximprei: dripstone and halite (salt)

(2) Organic processes of water-dwelling organisms form

biochemical sediments

Rock NameGroup Texture Composltton

Limestone

lnorganic

Clastic or non-clastic

calclte, u?uu3

Dolomite,CaMq(COs)z

Dolomite (Dolostone)Non-clastic

Non-clastic MicrocrYstallinequartz, SiOz

Chert

Rock saltNon-clastic Halite,NaCl

Non-clastic Gypoum,CaSOo'2HzO

RocK gYPsum

Calciie, CaCOg Limestone

OrganicClastic or non-clastic

ChertNon-clastic

Torc6sttc

MicrocrYstallineouartz, SiOzAltered Plantremains

Coal

-..

SedimentarY $tnuctu res

*provide additional information with regard to the depositional environment'

':rmed as bedding or stratificationl1, l-aYering [also t(

:l1.1 strataor bed: thickness of tftu layer is 1 cm or more

l.2taminafion:thicknessofthelayerislessthanlcm

*may result from differences,Qetween |ayers in texture (e.g., change in

grain sizei'ti*iui tomposition' color or cementation'

-beddingptanes.=flatsurfaces.alongwhichrockstendtoseparate

e end of one episode of sedimentation and the beginning of

another

(b)pauseindepositioncanleadtothecreationofbeddingplanes

2'Ripp|emarks.=smatlridgesofsandformedbymovingwindorwater

2,lCurrentripp|emardE:lfairorwaterismovingessentiallyinonedirection

2.2oscillatoryripplemarks:Resu|tfromtheback-and-forthmovementofsurface*.u"'inshal|owwaterenvironments

3'Cross.beddingisanarrangementofsmallbedsatanangletothemainsedimentarY laYering

by a Progressive4. Graded beddingdecrease in grain size

5'Mudcracksarepolygonul",.u.k,thatformwhenmudshrinksasiidries'

is a tYPe of bedding characterized

upwaid through the bed'

fiNETAMOffiFffiC RCCKS

Metarnorphic rocks = rocks resutting from changes in temperature andpressLtr'e ancl frotr changes in the chemistry of tlreir poi'e fluids.

= can be formed from igneous, sedimentary, orprevior-rsly nretanrorphosed rockb.

= solid-state .reaction= consist of a fabric of irrterlocl<ing crystal grains,

usually with preferred grain orientation.

*Changes -,,.t.* new minerals, textures and structures-')\

occur in the solid rock; witltout melting of rock

I. Principal agents of metamonphisrn

a. lentperature- rarely below 200oC, upper limit is ihe melting'temperature of

tlte tock

b. Pressurcli b.1 confiping/static = pressLr-e applied equrally on all surface of tlre

BT5r"r, ecl/dynamic - pressLrre applied unequally on the surfaceof a body

b.2.1 compressive - flattens objects perpendicular to appliedpfessLl[e

b.2.2 shearing flattens objects parallel to tlre applied

pressLlre

*Fcrliation - parallel arrangement of textural or structrrral featuresin apy type of rock; planar structure that results from flattening of

tlre constituent grains of a metamorphic rock'

c. Chentically active/migrating f/uids- loss and gain of ions and atoms- snrall arnir-rnt of pore fluid provides an inrportant medir-rrn of

transPotl

'Mletasornatisln

introduction of ions fronr an external

generally connected with magmatic

source

intrusions

I'r

T-- \l,/ilil

new material (front magma) + pore fluid = new mineralstable in the new chemical environment

l[. Types of metamorphlstm

a. Contact/thenmal metarnorphisrn = metamorphism resulting fromthe intrusion of lrot magma into cooler rocks.

*dorninant factor: temperatu re

fvlelarrorphitr

Qracle.

Ll. Regional metamorphism = metamorphism caused by relativelyhigh ternperature and both directed and confining pressure

= *affects broad regions of the Earth'scrrrst, usually in areas of tectonic activity. '

= foliation*heat: great depths, earth movements, batholiths"pressure: burial, tectonism

, | .t t,. -,:. .

c. l-lyclrothenmal nnetamorphlsm = metamorphism cauSed by

migratingftLridsandbyionsdissolvedinthehotfluids.lll. Textures of dretamorphic rocks .,,. .' .,

a. slaty = nearly perfect, planar, parallel fotiation of very fine glainedlplaty (flat) minerals (i.e , rnicas); low-grade tnetamorphism

,, l,l.t

, .li,..1,.,.....:,,.

b. Regional meta*orphi"* = metimorphiir .uru-d bg relatiu.lg high

ternperatrr. "nd

both directed unJ .ot fining Pressure= u{Qd..ts brood regions of th. Earth's

crLrst, urrullg itr areas of tectonie activity

= foliution

. ::::;:::1i : f i:i::': J *'m e n'fs1 ba'lh' h'lh s

c.. Hgdroth**uf meLamorphism = metarhotphitm .uut.d by nigrating

fl,ri,Js .und

bg ions dissoln.d in the hot fluids"

111. fct:turo of mctamorphic rocks

(..

a. slatg = nearlg pe#ect, planat-, purull.lfoliution of v.tg fine-grained

plu'y (flat) minerals (i.e., micas); low-grade metamotphi"t

phglliti. = s parallel (but wavg or wrinLled) foliatio n o[ [in"-g,ained

(ol.uu;onulig ,n.diur -g,uii.d) platg minerals (i..., misas and

chlorires), .ih,biting a silkg or me13llic lu*er; relativelg lo*-grad"

metamorphittt'

,.l",,rtose = purull"l to "ub-purallel

foliation of m.dium- to coarse-

qrained plutg ninerals (micas and nhlorite); intermediate-.to h'gh-

e."d* rnetamorphitt

gnei-ssrc = p^r"ll"l to uub-purull-l folirtio. of t.dium to coarse-

,:-.,ri,r"d platrl minerals in' alternating l.g"ru_ of difFerent

cc,mposition; jirter*-ditt"- tohigh-grade metatotphiut \ '

g rnoblustic = -rniform g;ain size o{ equant or- l.andomlg oriented

s:rains

:

l

t l ( | l. | |'-' r,l -'-'1--L-

l' I

t horntelsrc = tine-gained rocks with grains tendlngto be lntergrown

irr rarrdorn orientation

M. C.lassi$ication

A. tlnioliatud with qranular texture

b. rcliiated

oCataclastic roclcs= r.o.ks that htu. b."n granulated by .tuthing-

+ Mqlonite= uataclastic roclcs with floy textures-

Namc Texture Parcnt Rock

ate Slaty Tufl-, shale

P Slatg (silkg sheen);

phylliti.

Tuff, shale

,5chistose basalt, gabbro, tuf{-, andesite,

shal., rhgolit.

Gnciss Gneissose - Granite, rhale, diorite, ihgolite

*l

Deformationancllor shaPe

DIASTRC}PHISTJI / ROCK DEFORMATION

= a general term that refers to all, changes in r.'olume

of a rock bociY

= tfr" strain yielding of a solid to applieci stress ,

*Stress = the amount of force acting on. a rock unit to change its

shape and/or volttme

a. confining Pressure - equal

b. differential or dii'ecied. b.1 compressional - shorten a rock body

b.2 tensional - elongate or purll apart the rock

bodY

b.3 shear - sliPPage

*strain = is tlire.change in shape andior volume of a rock unit

caused bY stress

Iypes of deformation (strain):

a elastic deformation = object returns to iis original size and

shaPe when stress is removed

b. plastic.deformation =.a permanent change in the original

Lr,up* o.f a solid that occurs without fracture '

c. ruPturei , , '.'

Rocks that defcrm plastically by foldin$ and flowing are said to be

;;;;i;".' On'tf.'* otr'*r nanditoikt tested undqr surface conditlohs

],r""..t"i* -[Ji."irv, uri olce they exceed their elastic limit,

*"rt:b*hau* like a'brittle sblid and fractr:re- This type oi

l"t"i*"ti;; i. "orr*o

brittie failure'

--nlinelalswithstronginternalmclecularbonds;=brittle-- weaker bonds = ductile

-- qLrartzite, granite, gneiss = brittle

-- rock satt, [ypsum'-Marble and shale = ductile

L:. time

-- quicKtY = fracture

confining Rressure')

temperature /

Fqs+src '*f{e,o*rv,g -{Sa'bdhaviot of roo{rsl

a. inherent ProPerties mineralogy, gtain size, porosity etc'

high = plastic

,i,

e. solution - loulers rock strength

MAPPING GEOLCIGlc sTRUqliuRES

d

Outcrops - sites where bedrock are exposed

Attitude - refers to the 3D orientation of some geological feature

ex. bed, fracture

strike - direction of the line formed by the intersection of an

imaginary horizontal plane and any planar feature

- trend o ,

Dip.istheangleofinclinationofthesurfaceoftheplanarfeature **ur,-,r6d from the horizontal plane'

'4tt

FOLDS

Folc.ls - sinrply a bend or waverike undulations in bedding, foliation,ciea,;ace rir other planar featlrres

Parts of a fold:

, a. litnbs ar ilanks - twcr sides of a fold

b. hinge - line of maximum curvature in a folded bed

c. axr's - line paratlel to the hinge; line moving parallel to itselfthat generates the fold

d. axial plane - imaginary surface that divides a folci assymmetrically as possible

e. plunge- angle between the fold axis and the hor-izontal

Types of folds:

i.l. anticline = "arch"; convex upward

b. syncline. = arches downwarcl

d. synrmetrical = limbs clivergle atthe same angle

e. a$ymrnetrical

- overturned = one limb is iilted beyond the ver-ticalrecumbent = axial plane is horizontal

f. plunginE = iolcl with Cipping axis

g. monoclines = broaci flexures; one limb

h. domes and basiri

tt..,,

FRAC'TU RES

A" Joints = are fractures arong which no appreciabredisplacement has occurred

= may harre almost any orientaticn _ verticar,h o ri zo n ta',:::t

;"#:,Xifl '1.,=

Causes:

a. columnar joints form when igneous rocks cool and developshrinkage fractures

ex. Devil's Causeway in lrelandDevil's Tower in Wyoming

L-r. sheeting

c. rocks in outermost crust are cieforrneci

n" ,Joints may be significant from an economic standpoint*" ,Joints also present a risk to the construction of.engineeringprojects

B. Fadlts = are fractures in the Earth's crust along which slippageor displacement has occurred.

Fault terminology:

1. hanging wall = the rock above an inclined fault

2. footwall = the rock beneath an inclined fauli

Types of faults:

a. Dip slip fauits

a.'i normar/gravity faurts = extension; the hanging wail hasmoved down relative to ihe footwall '-"''7"'r 'uq'r rrq

6 graben (German word, "grave,;1 = wedge_shaped block ofrock dropped downward

' ll,H:;::"tnt of rock that have moved upward relative to

a.z reverse faurt = compr"rrion; hanging wail has moved up', relaiive to the footwall; high_angledi

I a.3 thrust fault = gompression; _hanging wall has moved up, relative to ihe footwail,; row-angred 1so" oi +6"i'-',

b- strike-slip faurts = raterar faurts; high-angre faurts in which thedisplacement is ho.rizontal, parallel to the stit<e of the fault plane,with little or no vertical movement.

b.1 right lateral stike-slip faulUdextral

b.2 left lateral strike-slip faulUsinisiral

c. Oblique slip faults

EARTHQUAKES AND REL

trernbling cf the earthEarthquake 'sudden motion or

- vibration in the earfh "ur.u-d

by ihe rapicl release of energy

*Most often are caused by slippage along faulis

Elastic Rebound TheorY:

oFl.f:. Reid, Johns Hopskins University

- slour deformation of the crust (creep) until strength of rock is

exceeded. Then, ruptttre cccurs' Start over'

- 1906 San Francisco Earthquake adhquake,

a. in the 50 y"u" before the 1906 san francisco e

surveys takln in the area recorcled an offset by creep over 3

, il:l"Ji,*nt during the 1906 eafthquake was 6 m, this movement

took plaiu in +O ieconds as opposed to 50 years

Focus - the poirrt at which vibrations of an earthquake originate

Epicenter-pointonsurfac*ot"",-tr.'irnmediatelyabo'vefocus

Rupturesurface-areaonafaultplanethatexperiencesmovementcluring an earlhquake event

^^,r atqcri, vels through rock, produced$eismic Waves .- any elastic waves that tra

by an earthquake or exPlosion

Whenanearthquakeoccuts,seismicWavesaregivenoff.Thisissimiiar to throwing a stone tntol quiet body of water' Wives are created

which move out fiom the point of impact

; and as it movesEnergy is being propagated along these paths

some of the energy is lost'

The farther the wave travels the lower its energY'

Seismograph - iirstrurnent that records seisrnic wav.es

Seismogram - record made by the seisnrograph

Types of seismic waves:

. 'i- Body waves - radiate outward from the focus in concentric spheresand travel through the Earth's intericr

a. P-waves - Primary waves, Longitudinal waves, CompressionWAVCS

- involves alternating compression and expansion of thematerial through which it passes

- similar to sound waves, like ihe nrotion of a spring or slinky, apush-pull rnotion

- movement of rock particles is parallel to the direction of wavepropagation

- fastest waves, travel 5 to 15 km/s- may pass through any kind of solids, liquids, or ga.ses

b. S-waves - Secondary waves, Shear waves, Transverse waves- inVolves oscillation of rock particles perpendicular to the

directionof propagation

- like sending a "wave' through a rope- slower than p-waves, 4-7 km/s- may pass through solids onlY

2. $urface waves - Long waves, L-waves- radiate outward from the epicenter and travel along the outer part

of the earth; generally slower than body waves- greater amplitude and longer period- cause the greatest destruction

a. Rayleigh vJaves - rock particles move in a vertical rolling(orbital) motion, something'like ocean waves

b. Love waves - rock particles move side to side in a horizontalplane

- very destructive and travel faster than Rayleigh waves

Pvelocit.v' } Syeto city > Lvelocity

Locatine an earthqrrake

- in orCer to locate an earthquake, at least three seismograph stationsare needed

- if only one station: distance to epicenter, along a radius from station- if two stations: two possible epicenter .

- three stations: unique point

Measurement of Earthquake Strenqth

a. lntensity - an indication of the destructive effects of an eartlrquake ata particular place

- affected by: distance to tire epicenter, total amount of energyreleased and nature of surface materials

- Mercalli scale (lflodified Mercalli Intensity Index)o qualitative and subjectiveo measure of damage and 'felt' intensityo determined by site'examination and interviews

b. Magnitude - total arnount of energy released during an earthquake- based on direct measLlrements of the size (amplitude) of seismicWAVES

- total ener$y reieased - calculated fi'om the amplitr-rde of the wavesand the distance from the epicenter

- Richter scaleo quantitativeo open ended, <1 to infinityo logarithmic (a magnitude 2 is 10 times more powerful than a

magnitude 1)

Effgcts of earthquakes1^ ground shaking and rupture2. landslides3. iiquefaction

4. tsunamis (seismic sea waves)

o originate when water is verticaily clisplaced during:earthquakes

' uncjersea landslides (turbidite fiows)undersea,rolcanic eruptions (e, g Krakatoa, 1683)

u6'F{ r rc\f Eo. rr, r- ,,'*rF I - lr r*a- t@ds. 4te4+_gAgrfih€4r&rmCoC,ffin tfic gm&rs sititace,charrging their positicns relaiive to one another

* ocean floor remains stationary as ihe contirrents ptowe( thror_rgh it

-- t'lot nev/:a. Buffon - sirnilarity in fossils

b. Snider-Pelligrini - similarity in coasilines*"l'lorth Arnerica and Europe

--'Alfred Wegener - Father of Continental Dr-iftcontinents had been united into a vast superccntinent calledPangaea (Pangea)

; a. Laurasia (northern) _ North America, Eurasia

i b. Gondwana (southern) - lndia and the rest of the continents

ii - driving mechanism: rotational and tidal forces

i -- Wegener's lines of evidence:'l

i a. ligsaw puzzle fit of the continents

,i b. distribution of fossil plants and animals

i examotes:

i b ] G/cs opteris sp. and Gangamopfe4rs sp.

, b.2 Lystrosaurus.sp. - found in Antartica, Inclia anc.l

I South America; land dwelleri (Why not North Arnerica? Distribution of fauna is

"r:::5X,.,,:uJ;:':'3 : )u,n

Arr e ri ca and s o u tir Arrica,i aquatic reptile:.li c. continuity of geotogic structures

- lndia, Africa, South America, Australia and Antartica . tillites'.

' j fossils

)l, i - identical patterns oi'scratches and grooves fornred in the,. rocks

I d. nt*terhs trf pateoclfn"atgs ard qlc"tehby,, rn +he Soratho-rn l-te.rrrsphere

,'1 ' - pr*,.r*I. ; r.,[.-*o, -+"r*otrt";

rn ftr*artica ,;;;;;;-'", once near tfie aqua*or

' .i.iFters v:. *i:rers - (tqao) cpiii-.aa< due rnainry io -rhe onc,r.0.,:t,ur,.,

ltlrrf

t' l

o in oPen ocearl: ^^^ , -,,^-a tlr?V travei uP to 700-800 km/hr

" wavelength >100-200 knt

r wave height <1 m)hing a coastlineo approacnlng d :"i:-'l:'^*^^^-r wavelengih decreases

. h;;;iintruu*", to compensate for low velocity (up to

30m) : '

' velocitY is reduced to < 60 km/hr

5. seiches (oscillating waves on surface of lakes' bays' rivers etc')

6. fire7. t"gionalbhanges in iand elevaiion

.Seismichazardmaps'hqyearthquaKeriskinaparticulararea.-indicateprobabilityofanevent,andprobabi|ityofacertainamount of ground shaking

- Short term Prediction

}some=u""",'byJapaneseandChinesebyuslng|u|eslother data

F factors considered useful: 3

'/ o"toimation of ground surface:";il;i**i tune connecst two .water-fill:: "::tuinersD gravimeters - measures changes in -.-graviiational

strength brought ab,out ,nV liting or falling land; of

;;iles in deisitY of rrnderlYing rock

' cf€e PrTleter u ' :-.. proton precession magnetometer - detects changes tn

[t"'* "u'ift's

magnetic fielcj

" lasers/ sesismic gaPs along faults r, -..'/ puiiurn= ind frequJn"y of earthquakes : :-,:1.'

",',' ,':,'.,,'.'',''',ir-..;':",-'

'/ uno*uf"tts animalbehavio l.. ,,

", :x1"#:3?".#Tl,o*r ,."=irliyily. . ,-----,-^li..a,^ n*i' 16 '-,-{CI. ,/, changes in wateri#;iltb'Jity' t**pe.rature in deep *ullt ',,ti,

.,,i.,,.tt,

, r .,,..

)> rocks contain minute amounts of magnetic minerals that align with the

earth's magnetic field

}.directionofalignmentandinclinationfromthehorizonta|indicatestheposition of the magneiic Pol"

within the rocks

the time and place the rocks formed

n studies show that poles were in.different positions relative to a continent

at various times in the geologic past

t "-o'",1it';:,'", had moved

(2) continents had moved

- continents stationary, poles had moved: paleomaqnetibally determinedpole positions for a particular time should be the same or all

continents

- continents had moved, poles stationary: pole positions slrould differ

among the continents

SEA FLOOR READIF,IG

-- Hess,oroposed that the sea-floor mighi,:l

fYlr)i/rn^I I rv v il ty

crest of the MOR doivn the flanksto disappear finally'by plunging

,- spreading'center = ridge crest- subduction = sliding of the sea

- Driving force of sea floor spreading:

neath a continent

a. Hess: SFS was clriven by ntle convection+ Meinesz and'Holmes hy earth's internal heat

r beneath the crest,

b' uplift of the spreading,ridge j jlstuoiunt formed simpry permits sridingv'rithout the help of conveltion curid:itll:

c' subductecJ slab is rnore dense b;g.urr" it is coid -;

tends to pullthe slab along as it dives .ri;i:ii,ii

Objections. : "

a. viscosity of the magma il ,

b. rocks are very weak under tensi.bn

iiliEvidence for SFS: iii ',

1' thickening of the sedimentary r3x,"r away from the ridgeItl

2 the age of the sediment restiilgi on the ocean floor increases awayfronr the ririge .:ii-,l'1..3.stripesofmagneticanomati"s,.i.:i,

" normar earth fierd - a!_ditir13,and str'ng magnetic intensity" reverse _ subtracts from tfleipr*="ni-ragnetic intensity.leaving elow vatue :ii . '

:'i:r '.:

eAding (1eo8)- "".1':;lT,$JLi.',-nit'ffi';iol;uu; reatures or the ocean r'1or

plus o'tit'nttt; ;i '' ea4hhuakes; mountain ranges'

volcanoes, etc illlil:l;l I i

Plate = large, mobile slab of rocf t{{Xt is part of the earth's surfacei:l1l i i

= large, mobile slab of rocf ii{dt is part of the earth's surface

: entirely "t idl#;oceanic crust' the continental

crust or both ifli\

= assumed to be rigid - t*o'$[drus on the same plate are not

- -r:^^ .^la*irro th each Othgnl

p uqrr. rrcrotrtigs rHEOnv

ilii

l'

: entirely "t idi& oceanic crust' the continental

in motion relative tb each othe;fii

iiiin/linot Plates:Major plates: il;,'--

,,.it.: li r. Southeast Asian-

1. American ,rli z. Nur"u2. Eurasian :ii' 3. CarriC"an3. African ::'

i. inJiun-Arlstralian ''ii 4' Arabta

5. pacific Lrqr'6'

ti ,5 Philippine

6. A.ntartic "l..^, iirr

L.iihosphere = earth's rigid outer shetli!

Astenosphere = Low Velocity Zonei rlue to an incre

=azonetrratnerr.au*$.pr"='icaltyduetoanincreasein Pressure and terRberature

= acts as a runritliilS iuv"t allowing the plates to

.lmove I 'ii

distinit unit' all maior interactions

between p\ates'occur along plate b 'oundariesI " t,:i ' - ^!: 'r" -rnd mountain building*

seismic activitY' volcanlsm a ,!i:'

a' divergent nouhdaiiS:- : where plates ff'.v,:

upu*,i"=iift'*g tt tllupyvellin$ of maierial from n

t; create new sea floor:r'

:,

b. conver-gent beundai-ies = wnere

together, causing orte of the slabs of the

be consumed into tHe mantle as it

. plates Inoveliihosphere todescends an

;r 11..,

A. Divergent Boundaries 'iii: :

a. oceanic divergence - mif,1ked by the crest of the MOR

and basaltic voicanoes :i'ii:

ex. Boun'dary behrueerili\azca and Pacific plates

'1,

b. continental divergence * niarked by rift valleys

ex. East African rift vallqys' Red Sea'

.t,:

B. Convergent boundaries :''

a. oceanic-oceanic' .onuBrg"n.* : ?, 9::alit plates

converge, one plaie subducts under the other

Features:

tVr:fe.

overriding plate

c. transform biundaries = whet'e plates slide

past eactr other creating or destroying lithospherei

::.

.;i.

a.1 Wadati-Benioff zones of earthquakesa.2 volcanoes I.

a.3 island arcs (Philippines, Japan, Tonga, Mariana)

a.4 inner wall of the"trench consists of a subduction

complex and fore-arc basin

Marianas type; fensioiip/ environment,' sfeep-ang/ed

st.rbducfiorr ',

oceanic-continental cohvergence - plate capped . by

oceanic crust is subducutecl under the continental piate

t:

b.1 subduciion complex,'fore-arc-basin, back-arc basin

b.2 edges of the continent become deformed into

young mountain ranbe I "

b.3' volcanic/magmatic.a.rc within the continental crust

continental-continental,Qonvergence - collision of ilvo

corrtinents ' .::

b.

'I

i

li

,l

':llen{:j11.1. :l ,: l:,

' ' : rrii":ii. ,' r'nl.iil;tu':'l:i:'i

, .,1:. r

,: :

r., :lr,:':it i

c.1 rnar-l<ed by sutr-rre zones (olci sites of subduction)c.2 majestically high mountain ranges in the interior'of

.aneWlargercontinerr:t(e.g.lndiaandAsia)c.3 marked by broad belt of shallow focus earthquakes

ali-,,1-l g the n u me[ousi:far-r lts

i':

3. -fransforil Bounrdaries iiiit::

marked by shailow focus eatfhqLiakes,rl:l:

- first motion studies indicateiil$trike-slip movement

ifi

What Causes ptate motions? 'itiilll

a. mantle convection - involves nCiO'con\ielJtion cells anr:i hotmantle rock ii'

,, due to: ilio a.1 magrna intrusionri on the ridge brest.prrshing tlre

plates ,.o a-? currents mov-ing away carry the plates

*"Push i-iypothesis" :1.

:

"difficurlt to account for the ve'pical.cracks in the rift zonei

b. sitbdt-rction pulls the plates :

*"Pull Flypothesis"

Ir\.

"nan account.for the tensional cracks but in.some ridgesthere are no trenches

i'r1....plurnes and hotspots ll*plumes - narrow colLtmns of hot mantle rock that rise anci

spreacl radially outwald formiiig hotspots of active volcarrismex. plurne under Hawaii

C.

, i{i,,,t$ii:jr

$'.i$,,$,

.ii:'. ,$',

,i it'',:' ii

iii,:

$ii

i;,,,.;,,',tr' :',j':.',:'.:.: t,

. , ,iri)lli

r:.l.1,:l

..