Convergent Boundary

A convergent boundary is when the plates come together. The cause of plates coming together is called a collision, when that happens the density decides which one comes on top. The ocean curb cools and spreads away from mid-ocean ridge. When the two plates carrying ocean crust meet trench, the plates with more pressure sink under the other. The less pressure continental crust can not sink under more pressure. Subductions happen as ocean plate sink beneath the continental plate. When two plates take continental crust collide, subduction does not happen. None of the pieces of the crust’s pressure sinks very far into the mantle. The mantle pushes the crust into mountain range.
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                                                Divergent Boundary

When two plates go away from each other, it happens along the mid-ocean ridge where sea-floor spreading happened too. When it happens on land the two plates slide apart. A deep valley is rift valley from around the divergent boundary.

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                                                Transform Boundary

Transform Boundary is when the plates slip past each other moving opposite direction. Earthquake often happen around transform boundary, but crust is none created or destroyed.
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