Oceanic-Continental Convergence
When an oceanic plate moves together with a continental plate, it falls and sinks underneath the continental plate and causes the plate to rise and create a mountain range. Even though this happens the very deepest part breaks into smaller pieces, which cause those pieces to break into tinier pieces. After all these broken pieces are locked in one place for a long time. It is then starts to cause earthquakes. There is a zone that is called the subduction zone. It is an area where an oceanic plate moves down under another plate into the mantle. Subduction zones that are along an oceanic-continental boundary to create deep-sea trench, they are: a long narrow, deep depresion in the sea floor. A lot of trenches occur all around the margin of the Pacific Ocean, because subduction. Sometime high temperatures can cause rock to melt all around the oceanic plate as it goes underneath the continental plate.
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