How are metamorphic rocks made?
1 Answer
Metamorphic rocks arise from the transformation of existing rock types, in a process called metamorphism.
Explanation:
The original rock or protolith, when subjected to heat and pressure, results in profound physical or chemical change. The protolith maybe sedimentary, igneous, or existing metamorphic rock.
They can form from tectonic processes such as continental collisions, which cause horizontal pressure, friction and distortion.
They are also formed when rock is heated by the intrusion of hot molten rock called magma from the Earth's interior.
Due to the action of plate tectonics, compression, stress and shearing forces over long periods of time, rocks can be essentially warped and deformed, causing them to be compacted into a smaller volume of space. As a consequence, metamorphic rocks are always more dense than their original materials, and also much less susceptible to erosions like breakdown.
