Trends of 'incipit'. Used Rarely. incipit is in the lower 50% of commonly used words in the Collins dictionary.
At the MOR, molten rock is carried upward towards the surface via convection, where new oceanic lithosphere is generated (usually as an fine-grained igneous rock known as basalt) and the plates are further pushed away from the spreading center.
Subduction boundaries occur where oceanic lithosphere is pushed beneath continental or oceanic lithospheres. Where two plates converge at an oceanic trench a subduction boundary is formed as cold oceanic lithospheres are pushed back down into the mantle. This happens because the oceanic plate is denser than the continental plate so, as they move together, the oceanic plate is forced underneath the continental plate. In this case, one plate overrides, or subducts the other, pushing it slowly downward into the mantle where it melts to form magma.