Geological and Environmental Sustainability

Volcanology & Plate tectonics

A volcano is a gap within the crust that permits molten rock from the mantle to effuse onto the surface as lava. Volcanoes also emit vast amounts of gas, primarily CO2, water vapor, and sulfur dioxide. The solid particles present in the atmosphere will remain for years. the good majority of seismicity on the earth occurs at plate boundaries, although intra-plate seismicity can occur also when stresses build up within the plate. Volcanism is related to two of the plate boundary types: divergent and convergent margins. the previous manifest themselves as long volcanic rifts mostly within the ocean basins whereas the latter typically make individual volcanoes on the plate that "wins out" within the collision process (i.e., doesn't subduct). Where two plates containing continental crust at their margins collide, there's little or no volcanism (such as at the Himalaya). Occasionally, plate boundaries where plates are mostly sliding by one another can experience small amounts of volcanism also if there's a component of extension across this boundary. Volcanism also can occur at intraplate volcanoes. These volcanoes are believed to possess sources deeper down within the Earth's mantle that remains during a relatively fixed location relative to the always migrating plate boundaries. Mauna Loa and Kilauea in Hawaii are the classic samples of intraplate volcanoes. Such volcanoes also can be seismically active, particularly when volcanic structures are built up rapidly. The crust must answer the additional load and relieves this stress through tectonic activity.