What is the magma source for mid- ocean ridge basalt?
A) by spontaneous melting in mafic magma chambers within oceanic crust
B) along block faults by frictional heating deep in the oceanic lithosphere
C) It all comes from Hawaii then flows out laterally along the ridge system.
D) decompression melting in the shallowest part of the asthenosphere beneath the ridge

Question

Quizplus · Accepted Answer

Decompression melting in the shallowest part of the asthenosphere beneath the ridge is the primary source of magma for mid-ocean ridge basalt. This process occurs as tectonic plates diverge at mid-ocean ridges, reducing the pressure on the underlying mantle, which leads to melting without the addition of heat.

What Is the Magma Source for Mid- Ocean Ridge Basalt