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S e dime ntary Ro c k • S e dime ntary ro c k is ro c k that is fo rme d fro m the ac c umulatio n and c o ns o lidatio n o f s e dime nts (we athe re d partic le s o f o the r ro c ks ) • Lithific atio n is the pro c e s s by whic h s e dime nts be c o me ro c k – Ex: s ands to ne , s hale , c o ng lo me rate Co mpre s s io n Co m p re s s io n o c c urs as the pre s s ure c re ate d by wate r and o ve rlying s e dime nts be c o me s g re at e no ug h to fo rc e partic le s o f s e dime nt c lo s e to g e the r, drive o ut any wate r, and c o mpac t the s e dime nts into ro c k A g o o d e xample is s hale S hale s Ce me ntatio n Ce m e ntatio n o c c urs as the additio n o f mine rals , s uc h as s ilic a, lime , o r iro n o xide , te nds to “g lue ” ro c k partic le s to g e the r to fo rm s o lid ro c k Example s are s and s to ne and c o ng lo m e rate , whic h are c o mpo s e d o f partic le s o f s and, pe bble s and s mall ro c ks S e dime ntary Ro c ks Co ng lo me rate S ands to ne Fo rmatio n by Che mic al Pro c e s s S o me s e dime ntary ro c ks fo rm as the re s ult o f c he mic al pro c e s s e s s uc h as e vapo ratio n and pre c ipitatio n Ro c ks fo rm e d b y the e v ap o ratio n o f w ate r are c alle d e v ap o rite s Example s are lime s to ne , ro c k s alt and ro c k g yps um um Example s o f S e dime ntary Ro c ks Fo rme d by Che mic al Pro c e s s e s Fo rmatio n by Bio lo g ic al Pro c e s s e s • S o me s e dime ntary ro c ks fo rm as a re s ult o f pro c e s s e s ac ting o n the re mains o f o nc e living o rg anis ms • Co al is fo rme d fro m the c o mpre s s io n o f de ad plants • Lime s to ne is fo rme d fro m the re maining s he lls o f de ad s e a-life Fo s s ils S e dime ntary ro c ks als o fo rm and c o ntain re mains o r impre s s io ns o f plants and animals The s e impre s s io ns are c alle d fo s s ils Kinds o f S e dime ntary Ro c ks Clas tic s e dime ntary ro c ks fo rm fro m the c o mpac tio n and c e me ntatio n o f frag me nts o f o the r ro c ks Che m ic al s e dime ntary ro c ks fo rm fro m mine ral g rains that pre c ipitate o ut by e vapo ratio n o r o the r c he mic al ac tio n Org anic s e dime ntary ro c ks fo rm fro m the re mains o f plants and animals Pro pe rtie s o f S e dime ntary Ro c ks Ro c ks may have o ne o r all o f the s e pro pe rtie s at the s ame time : • Dis c re te laye rs • Frag me ntal partic le s • Org anic c o mpo s itio n • Rang e o f partic le s ize s , o r – Pre minanc e o f o ne partic le s ize S e dime ntary S ample s Me tamo rphic Ro c k • Any kind o f ro c k c an be c o me a me tamo rphic ro c k • Me tamo rphic ro c k is ro c k pro duc e d by m o rp his m – Mo rp his m me ans to c hang e , s o the s e ro c ks are fo rme d by the trans fo rmatio n o f pre e xis ting ro c ks into dis tinc t ne w ro c ks • Me tamo rphic ro c ks fo rm as a re s ult o f the re c ry s taliz atio n o f unme lte d mate rial unde r c o nditio ns o f e xtre me ly hig h te mpe rature and pre s s ure o ve r lo ng pe rio ds o f time Clas s ific atio n o f Me tamo rphic Ro c ks Te xture re fe rs to the appe aranc e and mine ral arrang e me nt o f me tamo rphic ro c ks Fo liate d ro c ks have mine rals that pre s s ure has alig ne d into lay e rs that are e as y to s plit Band ing o c c urs whe n the re are thin lay e rs o f alte rnating m ine rals Me tam o rp hic ro c ks are in m any w ay s s im ilar to the ir p are nt m ate rial Ho w Do e s Mo rphis m Oc c ur? Me tamo rphic ro c ks fo rm as a re s ult o f: – Hig h te mpe rature s – Hig h pre s s ure s – Co mbinatio n o f bo th – BUT w itho ut the ro c k m e lting in the p ro c e s s Type s o f Me tamo rphis m Co ntac t Me tam o rp his m o c c urs whe n mo lte n ro c k c o me s in c o ntac t with s urro unding ro c ks The he at fro m the mag ma alte rs the ro c k in c o ntac t with it Re g io nal Me tam o rp his m ac c o unts fo r the g re ate s t amo unt o f me tamo rphis m and o c c urs whe n larg e are as o f ro c k are unde r inte ns e he at and pre s s ure Me tamo rphis m Me tamo rphic Ro c ks Me tamo rphic Ro c ks What is the Ro c k Cyc le ? • The ro c k c yc le is a the o ry re lating to vario us ro c k fo rming pro c e s s e s o f the c o mmo n ro c k type s The Ro c k Cyc le Ro c k Cyc le Trans itio n Zo ne s • The pro c e s s that c re ate s a trans itio n zo ne be twe e n ro c k type is c o ntac t me tamo rphis m [...]... ils Mo re Fo s s ils 3 Kinds o f S e dime ntary Ro c ks Clas tic s e dime ntary ro c ks fo rm fro m the c o mpac tio n and c e me ntatio n o f frag me nts o f o the r ro c ks Che m ic al s e dime ntary ro c ks fo rm fro m mine ral g rains that pre c ipitate o ut by e vapo ratio n o r o the r c he mic al ac tio n Org anic s e dime ntary ro c ks fo rm fro m the re mains o f plants and animals Pro pe... unde r c o nditio ns o f e xtre me ly hig h te mpe rature and pre s s ure o ve r lo ng pe rio ds o f time Clas s ific atio n o f Me tamo rphic Ro c ks Te xture re fe rs to the appe aranc e and mine ral arrang e me nt o f me tamo rphic ro c ks Fo liate d ro c ks have mine rals that pre s s ure has alig ne d into lay e rs that are e as y to s plit Band ing o c c urs whe n the re are thin lay e rs o f alte... ks The he at fro m the mag ma alte rs the ro c k in c o ntac t with it Re g io nal Me tam o rp his m ac c o unts fo r the g re ate s t amo unt o f me tamo rphis m and o c c urs whe n larg e are as o f ro c k are unde r inte ns e he at and pre s s ure Me tamo rphis m Me tamo rphic Ro c ks Me tamo rphic Ro c ks What is the Ro c k Cyc le ? • The ro c k c yc le is a the o ry re lating to vario us ro