Though unseen the ocean floor is a volcanic hot bed where the tectonic plates collide and spread apart. New research reveals that when two parts of the Earth’s crust break apart, this does not always cause massive volcanic eruptions. The study, published in the journal Nature, explains why some parts of the world saw massive volcanic eruptions millions of years ago and others did not. The Earth’s crust is broken into plates that are in constant motion over timescales of millions of years. Plates occasionally collide and fuse, or they can break apart to form new ones. When the latter plates break apart, a plume of hot rock can rise from deep within the Earth’s interior, which can cause massive volcanic activity on the surface (sort of like blood from a skin cut).
Volcanoes are generally found where tectonic plates are diverging or converging. A mid-oceanic ridge, for example the Mid-Atlantic Ridge, has examples of volcanoes caused by divergent tectonic plates pulling apart; the Pacific Ring of Fire has examples of volcanoes caused by convergent tectonic plates coming together. By contrast, volcanoes are usually not created where two tectonic plates slide past one another.
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