Ch. 4 Notes (ig. rocks)

Question 1

What makes an intrusive ig. rocks?

Answer 1

Cooled magma in a magma chamber

Question 2

What makes an extrusive ig. rock?

Answer 2

lava

Question 3

What is an example of an ig. rock?

Answer 3

Mount Rushmore

Question 4

Magma

Answer 4

comprised on liquids, solids, and gas compnents

Question 5

generation of liquid in magma

Answer 5

melting

Question 6

crystallization

Answer 6

formation of solid crystal

Question 7

gaseous components

Answer 7

volatiles

Question 8

felsic

Answer 8

feldspar and silica- minor iron and magnesium

Question 9

Mafic

Answer 9

magnesium and iron

Question 10

Fine- grained

Answer 10

aphanitic (not visible)

Question 11

Phaneritic (visible)

Answer 11

coarse- grained

Question 12

coarse and fine-grained

Answer 12

Porphyritic

Question 13

Groundmass

Answer 13

the fine grained component of a porphyritic rock

Question 14

phenocryst

Answer 14

large crystals

Question 15

texture w/ spherical gas pockets

Answer 15

vesicular

Question 16

Pumice

Answer 16

ejected magma; cools quickly in the air

Question 17

glassy

Answer 17

cools v rapidly

Question 18

Breccia

Answer 18

angular fragments

Question 19

What are three ways to melt a rock?

Answer 19

decrease in pressure(bring towards surface)
add water
temp. increase (rare)

Question 20

Example of a mafic volcano

Answer 20

Hawaii

Question 21

example of a fasic volcano

Answer 21

mt. st. helens

Question 22

changing magma composition through incorporation of surrounding rocks

Answer 22

Assimilation

Question 23

along sed. bedding

Answer 23

sills

Question 24

across. sed bedding

Answer 24

Dikes

Question 25

inflated sed. rocks make a shallow dome

Answer 25

Laccolith