Metamorphism is driven by heat and pressure . High heat can cause rock minerals
ID: 152419 • Letter: M
Question
Metamorphism is driven by heat and pressure.
High heat can cause rock minerals to recrystallize in the process of metamorphism.
Rocks that are buried deep in Earth are subjected to equal pressure from all directions. This confining pressure can cause a phase chang e but does not fold rocks.
On the other hand, pressure from mainly one direction—as is the case of this metamorphic rock and like what happens at a convergent plate boundary—causes differential stress and often leads to folding.
Metasomatism is the process in which chemical-rich fluids can metamorphose rock by changing its chemical composition.
Most metamorphic rocks have the same chemical composition as their protoliths (the “parent rock,” or the original nonmetamorphosed rock from which a metamorphed rock was formed).
However, metasomatism actively changes their chemical composition, making it harder to determine the protolith.
Return to the Gigapan image. Closely examine the rocks for evidence of metamorphic agents. Determine the metamorphic agent(s), or main metamorphic process(es), of the dark metamorphic rock in the Gigapan image.
A). Heating and pressure in one main direction
B). Heating by the intrusion of light igneous rock only
C). Deep burial
A). Heating and pressure in one main direction
B). Heating by the intrusion of light igneous rock only
C). Deep burial
D). Exposure to chemical-rich fluids onlyExplanation / Answer
Going through the Gigapan images, the process for the metamorphic process is open B , i.e., the metamorphism has occurred due to heating by the intrusion of light igneous Rock only. The black Rock is an intrusion in the grey coloured Rock.
The black colored Rock is a clear result of a intrusion process.