Metamorphic Rocks Flashcards
rocks that have experienced change as a result of a change in conditions
Metamorphic Rocks
3 agents of metamorphic rock
Heat
Pressure
Fluids
Number one agent of metamorphism; speeds up chemical reactions and breaks down old minerals;
Heat
lines of same temperature
Isotherms
Increases with depth
Pressure
How much rock is above the given point in earth
Lithostatic Pressure
Not equally applied; stronger stresses in one direction; common in plate collisions
Differential Pressure
increase the speed of metamorphism
Fluids
Changing a protolith
Starter rock changes
Changes the texture
Creates layers
Bends crystals
Two types of metamorphic rocks texturally
foliated and nonfoliated
alignment of crystals
compositional layers
Foliated
No layering massive looking
crystalline appearance
nonfoliated
What controls what the metamorphic rock will look like
The protolith
minerals that make up a rock that can determine its grad3
index minerals
Shallow pressures; occurs in ocean basins; burial and compression of marine sediments; low intensity
Burial Metamorphism
