What kind of texture does igneous rock have when magma cools slowly?
Coarse-grained
100
What kind of rock is formed from lava that cools on the surface of the earth?
Extrusive igneous rock
100
If wind in a desert suddenly blew all the time, what kind of rock would not be able to form?
Sedimentary, silly!
100
The process in which sediment is dropped and comes to rest is.__________
Deposition
200
What is a natural occurring solid mixture of crystals of one or more minerals?
A rock.....what did you think it was?
200
What does all igneous rock begin as?
Magma
200
Name one way magma is formed.
Change in pressure, change in temperature or change in composition
200
What is erosion?
Erosion is the process in which sediments are carried away from their source.
200
When sedimentary rock is exposed to heat and pressure, what does it change into?
Metamorphic
300
What are the 3 main classes of rocks?
Igneous, sedimentary and metamorphic
300
Name a coarse-grained rock that you have seen in this class.
Granite
300
What is the largest of all intrusive igneous rock formations?
Batholiths
300
What kind of sedimentary rock is made from fossils?
Organic
300
Partially decomposed plant material forms this sedimentary rock
Coal
400
Name the 4 processes that help shape Earth's surface.
Weathering, erosion, deposition and uplift
400
What is a fissure?
A fissure is a long crack in the earth's crust through which lava erupts and flows.
400
Mud cracks form when fine grained sediments are exposed to the air and do what?
Dry out
400
What are the main categories of sedimentary rock?
Clastic, chemical and organic
500
What is the difference between composition and texture?
Composition is the minerals the rock is made of and texture is the appearance of the rock based on the arrangement of the minerals from which it is made.
500
You are walking on land where a volcano was once active. You pick up a rock that is smooth and appears to have no crystals. How do you think this rock was formed? (full answer, please)
The rock is an extrusive igneous rock that was made from lava and cooled very quickly.
500
How does the rate at which magma cools affect its texture?
The more time magma takes to cool, the larger the crystals. If magma cools quickly, the crystals are very small or not there at all.
500
How is clastic sedimentary rock different from chemical sedimentary rock?
Clastic--formed from rock fragments that are cemented together
Chemical--made of dissolved minerals that eventually recrystallize