Who was James Hutton and what is uniformitarianism?
A rock is a group of minerals bound together in some way.
Formed by the cooling and hardening of hot molten rock inside the earth (magma).
There are two types of Igneous Rock!
Plutonic - (INTRUSIVE) Rocks that form underground from cooled magma.
These rocks are seen as the surface wears away.
Have a distinct mineral composition.
Volcanic - (EXTRUSIVE) Rocks that form when the lava cools
Lack distinct mineral composition.
There are two different types of magma!
Felsic magmas form light-colored, silica rich rocks.
Such as granite
Mafic magmas form dark-colored, ferromagnesian-rich rocks.
Such as basalt
Texture depends on the rate at which magma cools.
The slower the magma cools, the coarser the texture.
A porphyry is a rock with two distinct textures.
Formed by the hardening and cementing of layers of sediment.
Why did Chef Purnell make pancakes and call them metamorphic rocks?
What is the rock cycle?
Grouped by kind of sediment!
Clastic
Chemical
Organic
Clastic - sorted by water action before pressure and mineral cements turn them into rock.
Sometimes layers are evident because of the different sediment types on top of each other.
Examples of sedimentary rocks with layers...
Fossils
Ripple Marks
Mud Cracks
Nodules
Concretions
GeodesMetamorphic Rocks (Pancakes!!! WooHoo)
They are formed when heat or pressure or both change the density, mineral, and structure of existing rocks.
2 types of metamorphic Rocks
Regional metamorphism results from the heat and pressure of mountain-building and affects large areas.
Contact metamorphism results when hot magma is in contact with rock; it affects small areas.The Rock Cycle
You should be able to draw the cycle for the test!
The rock cycle shows how the formation of igneous, sedimentary, and metamorphic rocks are interrelated.
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