What is/are thought to be the main mechanism(s)for generating basaltic melts from hot peridotite near its melting point in the upper mantle?
A)conductive heating of basaltic ocean crust subducted into the mantle
B)frictional heating of basaltic ocean crust as it slides down subduction zones
C)intrusion of hotter solid mantle rocks from below
D)drop of confining pressure or introduction of water

Question

Quizplus · Accepted Answer

The drop of confining pressure or introduction of water is thought to be the main mechanism for generating basaltic melts from hot peridotite near its melting point in the upper mantle. This can occur due to processes such as decompression melting or hydration melting, which result in the release of volatiles (e.g. water) and a reduction in the melting temperature of the mantle rocks. In contrast, options A, B, and C involve heating of pre-existing basaltic rocks rather than peridotite, and are not considered to be primary mechanisms for generating basaltic melts from peridotite.

What Is/are Thought to Be the Main Mechanism(s)for Generating Basaltic