Question

The two most important sources of heat for metamorphism are:

1) intrusive magma bodies and deep burial.
2) intrusive magma bodies and heat from the core.
3) deep burial and volcanism.
4) radioactive decay and volcanism.
5) radioactive decay and deep burial.

Answer 1

The two main sources of heat for metamorphism are heat from intrusive magma bodies and the geothermal gradient. Option number 1 is correct.

Step-by-step explanation:

The two most important sources of heat for metamorphism are heat from intrusive magma bodies and the geothermal gradient. Intrusive magma bodies, like magma chambers, provide localized heat that can metamorphose surrounding rocks, a process referred to as contact metamorphism.

The geothermal gradient represents the overall increase in temperature with depth in the Earth, which, along with increasing pressure, leads to regional metamorphism typically seen in mountain belts. These two sources of heat are critical in driving metamorphic processes, alongside pressure and the presence of chemically reactive fluids.