Explain how the processes that occur at mid-ocean ridges and ocean trenches illustrate the cycling of matter.

Explanation:

This uplifting of the ocean floor occurs when convection currents rise in the mantle beneath the oceanic crust and create magma where two tectonic plates meet at a divergent boundary. The other process proposed to contribute to the formation of new oceanic crust at mid-ocean ridges is the "mantle conveyor".