Metamorphic source rocks, the rocks that experience the metamorphism, are called the parent rock or protolith, from proto - meaning first and lithos- meaning rock. Most metamorphic processes take place deep underground, inside the Earth’s crust.
Metamorphic rocks form one of the three great divisions of rock types. They are distinguished from igneous rocks, which form from molten magma, and sedimentary rocks, which form from sediments eroded from existing rock or precipitated chemically from bodies of water. [8] Metamorphic rocks are formed when existing rock is transformed physically or chemically at elevated temperature, without ...
Learn about metamorphic rocks in geology. Discover how they form, the types, examples, and how to identify them.
Metamorphic rock, any rock that results from the alteration of preexisting rocks in response to changing conditions, such as variations in temperature, pressure, and mechanical stress, and the addition or subtraction of chemical components. The preexisting rocks may be igneous, sedimentary, or other metamorphic rocks.
Metamorphic rocks start as one type of rock and—with pressure, heat, and time—gradually change into a new type of rock.
Metamorphic rocks started out as some other type of rock, but have been substantially changed from their original igneous, sedimentary, or earlier metamorphic form. Metamorphic rocks form when rocks are subjected to high heat, high pressure, hot mineral-rich fluids or, more commonly, some combination of these factors. Conditions like these are found deep within the Earth or where tectonic ...
Metamorphic rocks form when high temperatures and pressure act on a rock to alter its physical and chemical properties (metamorphism means 'to change form'). These conditions often stretch, twist and fold the rock as it cools. In metamorphic rocks some or all of the minerals in the original rock are replaced, atom by atom, to form new minerals.