When the ocean plates sink deep enough, portions are melted by the intense heat generated within the mantle, turning the solid rock into molten magma.

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They are also trying to understand the role that deep seas trenches play in earthquakes - these cracks in the sea floor are formed at the boundary of two tectonic plates and some believe the push and pull taking place deep underwater could be the cause of major earthquakes, such as the 2011 quake that resulted in such devastation in Japan.

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But it was only three years ago that vents were first detected in the Cayman Trough, a deep trench formed by the boundary between two tectonic plates.

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