Subduction zones are common sources of volcanoes. Explain the key details of the process of volcano formation along subduction zones
What will be an ideal response?
ANSWER: ?The subducting oceanic plate has a high water content. This water boils off as it descends and rises under the peridotite supporting the continental plate above. The water allows the magma to melt at a lower temperature. The peridotite melts to form basaltic magma, which is less dense than its surroundings and begins to rise. The rising basaltic magma can melt granitic rock to form rhyolite. Either the rhyolite, basalt, or intermediate andesite magma melts through to the surface to form a volcano.
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