rocks are compressed
... that as rocks are compressed, sinking down into an oceanic trench, they release water that causes volcanoes to form above?
... that as <b id="mwCQg"><a href="./Subduction_zone_metamorphism" id="mwCQk" rel="mw:WikiLink" title="Subduction zone metamorphism">rocks are compressed</a></b>, sinking down into an oceanic trench, they release water that causes volcanoes to form above?