In contact metamorphism - a nearby magma melt.
In regional metamorphism - the geothermal gradient from the mantle/core
In mylonites, the heat of friction across the fault plane.
In astroblemes, the kinetic energy of the impactor.
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The origin of the heat that creates metamorphic rock can be from friction caused by colliding plates, but by far the vast majority of the heat has originated in Earth's interior, caused by radioactive decay, remnant heat from Earth's formation, and pressure.
Contact metamorphism results from contact with or proximity to an igneous intrusion. Most of the heat for contact metamorphism is supplied by magma.
Most of the heat for contact metamorphism is supplied by a nearby mass of magma. Heat is the primary agent for contact metamorphism.
Heat is generated by the friction of sliding along the zone, and the rocks tend to crushed and pulverized due to the sliding.
A nearby mass of magma.
A nearby mass of magma
Geotharmal gradient
Heat and pressure causes Metamorphic Rocks to form.
Melting of the bulk of the metamorphic rock, then solidification from cooling, will form an igneous rock.
intense heat and pressure.
Metamorphic rocks are often found deep under the earth's surface because metamorphic rocks form from heat and pressure. Therefore, they form while they are under the earth's surface.
Heat, Pressure, and Chemically active fluids.
Heat, for sure, and most often a combination of heat and pressure is needed for metamorphic rock creation.
Metamorphic rocks form from heat and pressure.
Heat and pressure causes Metamorphic Rocks to form.
Heat
Metamorphic rock
Metamorphic rock is not formed directly from magma. Igneous rock is formed from the solidification of magma and lava.
Melting of the bulk of the metamorphic rock, then solidification from cooling, will form an igneous rock.
Heat and pressure.
You need to increase heat and / or pressure for a metamorphic rock to form.
Earths hot interior
Earths hot interior
Metamorphic Rocks are rocks that have changed form due to heat and pressure.