Metamorphic Rocks Flashcards
How are metamorphic rocks changed?
By heat, pressure, or chemically active solution
How are metamorphic rocks classified?
By texture, mineral assemblages, and grade
Where would most metamorphism occur at?
Near convergent or former convergent plat boundaries
What are the agents of metamorphism?
Heat, pressure, and chemically active solutions
What are the 3 types of metamorphism?
Regional, Contact, and Dynamic
What helps form regional metamorphism rocks?
Pressure, heat, and stress (convergent) at great depth
What helps form contact metamorphism rocks?
Heat along intrusions
What helps form dynamic metamorphism rocks?
Faulting, pressure, and stress (transform) near the surface
What does metamorphic textures refer to?
Size, shape, and arrangement of grains
What are the 2 types of metamorphic textures?
Foliated & Nonfoliated
Where are most foliated metamorphic rocks?
Convergent plate boundaries and subduction zones
What’s foliation?
Layered structure, parallel alignments of flattened mineral grains and pebbles
What kind of stress do rocks before and after metamorphism?
Before: Uniform
After: Differential
What’s the metamorphism process for shale?
Shale -> Slate -> Phylite -> Shist -> Gnesis -> Granite
What are some examples of nonfoliated metamorphic rocks?
Marble and Quartzite
What’s regional metamorphism?
Foliated metamorphic rocks and changes in texture with increasing heat and pressure
What’s dynamic metamorphism?
Crushing, grinding, and reorganization of rock along fault zones
What’s another words for word for fault zones?
Mechanical deformation
What’s fault breccia?
Dynamic metamorphism shallow in the crust
What’s mylonite?
Dynamic metamorphism deep in the crust
Where does low temperature and high-pressure zone occur on convergent plate boundaries?
Very close to the oceanic crust
Where does high temperature and high-pressure zone occur on convergent plate boundaries?
Between the low temperature and high-pressure zone and the high temperature and low-pressure zone
Where does high temperature and low-pressure zone occur on convergent plate boundaries?
Near the middle of the formation of a volcano
What is the setting for regional metamorphism?
Regional metamorphism
What is the metamorphic process for limestone?
Limestone -> marble
What is the metamorphic process for sandstone?
Sandstone -> Quartzite
What are the characteristics of nonfoliated metamorphic rocks?
Grains stay oriented and are most hornfels
What’s breccia?
Broken up, angular rock debris cemented together
What’s another word for contact zone?
Hornfels that are baked
What’s the dark sill intruded in hornfels?
Mafic
