What process links the deep water cycle to surface phenomena like volcanism?

Answer

Dehydration melting

As water-heavy ringwoodite descends, it transforms into silicate perovskite, which cannot retain the water. This forces the H2O out, triggering partial melting of the rock, a process known as dehydration melting, which generates magma.

What process links the deep water cycle to surface phenomena like volcanism?
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