What is the process called when different minerals in rock melt at different temperatures?

What is the process called when different minerals in rock melt at different temperatures?

• A. Crystallization
• B. Weathering
• C. Metamorphism
• D. Partial melting

Answer: (D)

Partial melting is the process where a rock made of several minerals starts to melt only in part because each mineral has its own melting temperature. As heat rises, minerals with lower solidus temperatures melt first while higher-temperature minerals stay solid. The liquid that forms is a partial melt and is enriched in the components that melt early, leaving behind a solid residue depleted in those components. This explains how magma can originate from solid rocks and why magmas often have different compositions than their source rock. Other processes are different: crystallization is the formation of crystals from a melt as it cools; weathering breaks down rocks at the surface; metamorphism changes minerals under heat and pressure without melting.

Partial melting is the process where a rock made of several minerals starts to melt only in part because each mineral has its own melting temperature. As heat rises, minerals with lower solidus temperatures melt first while higher-temperature minerals stay solid. The liquid that forms is a partial melt and is enriched in the components that melt early, leaving behind a solid residue depleted in those components. This explains how magma can originate from solid rocks and why magmas often have different compositions than their source rock. Other processes are different: crystallization is the formation of crystals from a melt as it cools; weathering breaks down rocks at the surface; metamorphism changes minerals under heat and pressure without melting.