Studies of the chemistry of rocks from arc volcanos indicate the main source of the magma is ________.
A)melting of subducted oceanic crust
B)melting of the subducted mantle lithosphere
C)melting of the asthenosphere above the subducting oceanic plate by frictional heating on the subduction interface
D)melting of the asthenosphere above the subducting oceanic plate by fluids acting as a flux to enhance melting

Question

Quizplus · Accepted Answer

Studies have shown that the main source of magma in arc volcanoes is the melting of the asthenosphere above the subducting oceanic plate. This melting is often enhanced by the presence of fluids, such as water, which act as a flux to lower the melting point of the rocks. This process is referred to as fluid-assisted melting or flux melting.

Studies of the Chemistry of Rocks from Arc Volcanos Indicate