Without convection, there would be no volcanoes on Earth because
A) all the convecting material spurts out at the surface.
B) rising mantle material undergoes decompression melting.
C) molten outer-core melts the lower continental crust.
D) volcanoes sink down into Earth near down-going convention cells.

Question

Quizplus · Accepted Answer

Convection is the main process that drives plate tectonics and magma generation on Earth. Without convection, the mantle would cool and solidify, and there would be no melting or upwelling of material to form volcanoes. The rising mantle material undergoes decompression melting to form magma chambers, which eventually lead to volcanic eruptions at the surface. Therefore, choice B is the correct answer.

Without Convection, There Would Be No Volcanoes on Earth Because