Chapter 7 Flashcards
Metamorphism
When a rock changes due to heat and pressure. It is distinctly different from its mother rock.
Metamorphic Rock
A rock produced by metamorphism
Parent Rock (protolith)
What a metamorphic rock morphs from.
Ductile (Plastic)
Capable of being molded and bend under stress.
What is the parent rock of Marble
Limestone it can also be calcite.
How are metamorphic rocks brought to the surface?
because of erosion and the uplift of mountain belts
Confining Pressure
Pressure applied equally on all surfaces of a body.
What is the pressure gradient under the earths crust?
1 Kilobar for every 3.3 meters of burial in the crust.
stress
A force that applies pressure and usually changes the shape of the object.
Differential Stress
When pressure on a body are not of equal strength in all directions.
What is Shearing?
Movement in which parts of a body slide relative to one another and parallel to the forces being exerted. In simple terms, think of shearing a bolt.
How important is Hot Water(as vapor) in the creation of metamorphic rocks?
It is the most important.
What is Foliation
Parallel alignments of textural and structural features of a rock. It’s kind of like those videos were they fill a tree stump full of epoxy and then they plain it and everything is thin and stretched.
What is Foliation
When a metamorphic rock forms sheets or layers from the direction of pressure that was applied.
Slate
A fine Grained rock that splits easily along flat parallel planes.
Phyllite
A metamorphic rock in which clay minerals have recrystallized into microscopic micas, giving the rock a silky sheen.
What are the characteristics of Schist? (Mr. Mosers favorite rock)
A metamorphic rock characterized by coarse grained minerals oriented approximately parallel. It has crystals that are visible to the naked eye. Its chemical composition is relying on the parent rock as well as the temperature it was formed at and pressure.
Gneiss
A metamorphic rock that was created under intense heat and pressure. You can visibly see the foliation.
What are the characteristics of slate?
Fine grained formed from shale under low heat and pressure.
What are the three types of metamorphism?
- Contact
- hydrothermal
- reginal