Rock Cycle/Igneous

Question 1

What is a rock?

Answer 1

Naturally occurring solid compound made up of an aggregate of minerals or a body of glass

Question 2

What is an igneous rock?

Answer 2

Rocks that form from the freezing of melt (magma/lava)

Question 3

What are sedimentary rocks?

Answer 3

Grains or other pieces of hard rock get glued together to form a coherent solid

Question 4

What are metamorphic rocks?

Answer 4

A pre existing rock undergoes solid state change in response to the modification of its environment at depth

Question 5

What is foliation?

Answer 5

Alignment of mineral grains

Question 6

What can all 3 types of rocks do?

Answer 6

Produce all 3 types of each other

Question 7

How do igneous rocks form? And what temps do they form?

Answer 7

From the freezing of melt and they form at around 650 to 1100 Celsius

Question 8

What is it called when melt is below and above surface?

Answer 8

Below=magma above=lava

Question 9

What are rocks when they form from the freezing of magma?

Answer 9

Intrusive Igneous Rocks

Question 10

What are rocks when they form from the freezing of lava?

Answer 10

Extrusive Igneous Rocks

Question 11

Where can melt form?

Answer 11

In special places where pre-existing rock is able to melt under high temps or pressure

Question 12

Define Geotherm

Answer 12

Curved line on a graph that compares temp, pressure and depth

Question 13

Describe decompression melting & what boundary is it associated with?

Answer 13

Temperature stays the same, pressure decreases (divergent boundaries)

Question 14

Describe flux melting and what boundary is it associated with?

Answer 14

Hot rocks mix with volatile minerals causing melting to occur (Convergent boundaries)

Question 15

Describe heat transfer melting

Answer 15

Heat from magma melts rocks around it

Question 16

What helps us describe melts?

Answer 16

oxides

Question 17

What are the 4 groups that we can describe igneous rocks in?

Answer 17

felsic, intermediate, magic, ultramafic

Question 18

Describe felsic rocks

Answer 18

Light, highest amount of silica, 66-76% S.O

Question 19

Describe intermediate rocks

Answer 19

Intermediate in color, 52-66% Silica

Question 20

Describe mafic rocks

Answer 20

dark, 45-52% S.O

Question 21

Describe ultramafic rocks

Answer 21

dark green in color, olivine, 38-45% S.O

Question 22

What do the 4 compositions reflect in a rock

Answer 22

Where it came from

Question 23

How much of a rock can melt to produce magma?

Answer 23

2-3%

Question 24

What happens to rocks that form from partial melting?

Answer 24

they become more felsic

Question 25

What would partial melting of an ultramafic source produce?

Answer 25

Mafic Igneous rocks

Question 26

How could magmas become more mafic?

Answer 26

Heat transfer melting

Question 27

How could melt become more mafic?

Answer 27

Iron+Mg rich materials enter

Question 28

How does magma rise

Answer 28

magma becomes less dense

Question 29

What happens when heavy rocks create pressure

Answer 29

magma is squeezed upwards

Question 30

What is viscosity

Answer 30

Resistance to flow

Question 31

Is felsic or mafic mage more viscous

Answer 31

felsic

Question 32

What does viscosity depend on

Answer 32

temp, silica count, gas content

Question 33

What happens if melt reaches the surface opposed to staying below

Answer 33

it cools faster

Question 34

Describe faster vs slower cool

Answer 34

Faster: lava, extrusive,smaller crystals Slower: Magma, Intrusive, Larger crystals

Question 35

what factors control cooling

Answer 35

size and shape, depth, water

Question 36

What are the first minerals to crystallize

Answer 36

mafic minerals (Iron-Mg-Rich)

Question 37

What is a dike?

Answer 37

tabular intrusion that cross cuts pre existing layers

Question 38

What is a sill?

Answer 38

tabular intrusion that is parallel to preexisting layers

Question 39

What is a Laccolith?

Answer 39

Blister shaped intrusion that domes up overlying layers

Question 40

What is a pluton?

Answer 40

Blob Shaped intrusion that extends for 10's of kilometers

Question 41

What is a batholith?

Answer 41

Blob Shaped intrusion that extends for 100's of kilometers