Rocks and minerals 3 sedimentary

Se dime ntary Roc ks... • Co al is fo rmed from the co mpres s io n Co al of dead plants... 3 Kinds of Se dime ntary Roc ksClas tic Clas tic s edimentary rocks form from the compactio

Se dime ntary Roc k

• Se dime ntary ro c k is roc k that is

formed from the ac cumulatio n and

c ons olidation of s ediments (weathe re d particle s of o the r ro cks ).

• Lithific atio n is the pro c es s by whic h

s edime nts be co me roc k.

– Ex: s ands tone , s ands tone s hale , s hale cong lomerate

tog ethe r, drive out any wate r, and

co mpact the s e diments into ro c k.

A g oo d example is s hale s hale

Shale s

Ce me ntation

Ce m e ntation

Ce m e ntation oc c urs as the additio n o f

mine rals , s uc h as s ilic a, lime , or iro n oxide , te nds to “glue ” ro c k partic le s toge the r to fo rm s o lid ro c k.

Example s are s ands tone and s ands tone

c onglom e rate

c onglom e rate , whic h are c o mpo s e d

of partic le s o f s and, pe bble s and

s mall ro c ks

Se dime ntary Roc ks

Formation by Che mic al Proc e s s

So me s edime ntary roc ks fo rm as the

re s ult o f che mic al proc e s s e s s uc h as evapo ratio n and pre cipitatio n.

Ro c ks fo rme d b y the e v apo ratio n o f

w ate r are c alle d e v ap o rite s

w ate r are c alle d e v ap o rite s

Example s are limes tone lime s tone , rock s alt roc k s alt and

ro c k g yps um

Example s of Se dime ntary Roc ks Forme d by Chemic al Proc e s s e s

Formation by Biolog ic al Proc e s s e s

• Some s edimentary rocks form as a

re s ult o f pro ce s s es acting o n the

re mains o f o nce living org anis ms

• Co al is fo rmed from the co mpres s io n Co al

of dead plants

• Lime s to ne is formed fro m the Lime s to ne

re maining s he lls o f de ad s e a-life

Fo s s ils

Se dime ntary ro c ks als o form and als o fo rm and

c o ntain re mains o r impre s s io ns

of plants and animals The s e

impre s s io ns are c alle d fos s ils fo s s ils

Fos s ils

More Fos s ils

3 Kinds of Se dime ntary Roc ks

Clas tic

Clas tic s edimentary rocks form from the

compaction and cementation of frag ments

of other rocks

Che mic al

Che mic al s edimentary rocks form from

mineral grains that precipitate out by

evaporation or other chemical action.

Organic

Organic s edimentary rocks form from the

remains of plants and animals

Prope rtie s of Se dime ntary

Roc ks

Roc ks may have one o r all o f the s e pro pe rtie s at the s ame time :

• Dis c re te laye rs

• Fragme ntal partic le s

• Organic c o mpo s itio n

• Range o f partic le s ize s , or

– Predominance of one particle s ize

Se dime ntary Sample s

fo rme d by the trans fo rmatio n o f pre e xis ting ro c ks into dis tinct ne w ro cks

• Metamorphic rocks form as a res ult of the

re c ry s talization of unmelted material under

conditions of extremely hig h temperature and pres s ure over long periods of time.

Clas s ific ation of Me tamo rphic Ro c ks

Te xture refe rs to the appe aranc e and

mine ral arrang eme nt of metamorphic

ro c ks

Fo liate d ro cks have minerals that

pre s s ure has alig ned into lay e rs that are eas y to s plit.

Banding o cc urs when the re are thin

lay e rs o f alte rnating m ine rals

Me tamorp hic roc ks are in many w ay s

s im ilar to the ir pare nt mate rial.

How Doe s Morphis m Oc c ur?

Me tamo rphic ro c ks form as a res ult fo rm as a re s ult

o f:

– Hig h te mpe ratures

– Hig h pre s s ures

– Co mbinatio n of both

– BUT without the rock melting in without the roc k m e lting in

the proc e s s

Type s of Me tamorphis m

Contac t Me tamorphis m occurs when molten rock comes in contact with s urrounding rocks

The heat from the mag ma alters the rock

in contact with it.

Re gional Me tamorphis m accounts for the

greates t amount of metamorphis m and

occurs when larg e areas of rock are under intens e heat and pres s ure.

Me tamorphis m

Me tamorphic Roc ks

Me tamorphic Roc ks

What is the Ro c k

Cyc le ?

• The rock cycle The roc k c yc le is a the ory

re lating to various roc k

forming proc e s s e s of the

c ommon roc k type s

The Roc k Cyc le

Roc k Cyc le Trans ition Zone s

• The proces s that creates a trans ition

zo ne be twe en ro c k type is co ntac t

me tamo rphis m