Study guide Dynamic Earth Unit 3 Test
What happens to the crust when large amounts of sediment are deposited in a short amount of time?
The crust subsides due to the weight
What physical change takes place when igneous rock changes to sedimentary rock?
weathering
What part of the rock cycle helps form igneous rock but not other types of rock?
melting
What part of the rock cycle helps form sedimentary rock but not other types of rock?
erosion
How does acid rain affect different types of rock?
It dissolves some rock faster due to their different compositions
Define uplift
The rising of regions of the crust to higher elevations
Define weathering
Breaks down rocks into sediment
Define subsidence
The sinking of regions of crust to lower elevations.
How did the sedimentary rock in the Grand Canyon form?
Sand and other material being deposited over time
What happens to basalt or any other rock over time?
All rocks change over time.
Define deposition
The process by which eroded material is dropped
Give some examples of depostion
Falling of volcanic ash to earth, sediments being deposited into a delta or alluvial fan.
How does metamorphic rock change to sedimentary rock?
Metamorphic rock -> weathering -> sediment – > erosion -> deposition –> sedimentary rock
What change of state happens when magma turns into igneous rock?
Liquid to solid
Which cause more weathering acid rain or normal rain?
Acid rain
What causes rocks in a river to erode?
Flowing water
What is a rift zone?
An area where deep cracks form. This is common between tectonic plates
Where does foliated metamorphic rock form?
Deep below the surface
What condition changes the rock that is deep below the crust of the Earth?
High pressure
What is clastic sedimentary rock and where does it form?
Sedimentary rock that forms when sediments are buried, compacted and cemented / in deltas
What describes the rock that will eventually form at the surface after a volcano erupts?
Extrusive igneous rock
How does basalt form and what class of rock does it belong to?
Forms when lava cools at the surface / basalt is extrusive igneous rock
How does granite form and what class of rock does it belong to?
Forms when magma cools / granite is intrusive igneous rock
Define cementation
The cementing together of layers of clasts
What do conglomerate, sandstone and, siltstone have in common?
They are all clastic sedimentary rock
What is texture in relation to rocks? Give examples.
It describes size, shape , and position of grains
What effect does the rate at which magma cools have on the texture of igneous rocks?
The faster it cools the smaller the crystals
What is a direct source of material in the formation of metamorphic rock?
Existing rock
What is one difference between a mineral and a rock?
Rocks can be made of crystalline or non-crystalline material / minerals are always made of crystals
What type of rock is classified as chemical, clastic and organic?
Sedimentary rock
Define lava
Lava is magma that erupts onto the earth’s surface
Define magma
Magma a mixture of molten rock, volatiles and solids beneath the surface of the Earth
How can a rock’s texture give clues to its origin?
Looking at the rounded clasts that are cemented together in a sedimentary rock is one way
to identify through texture.
What type of change takes place when granite turns to gneiss?
Igneous rocks changes to metamorphic rock
What do basalt and granite have in common?
They are both igneous rocks
What type of rock is made when layers of material become compressed?
Sedimentary rock
What is the rock cycle? Be able to diagram it.
The series of processes in which rock changes from one type to another
Diagram – see textbook pages 160 - 161