... the volume of the earth. The asthenosphere is plastic like due to partial melting, unlike the lithosphere which is solid but semi-rigid and can flex. The lithosphere is capped by the crust, the final layer of the earth. This is a less dense layer and very thin in comparison to the core and mantle. There are two types of crust, being oceanic and continental. Continental crust is generally thicker and less dense than oceanic. Plate tectonics are concerned with the movement of lithospheric plates, which are chunks of lithosphere with their crustal caps. The earth's surface consists of seven major and thirteen minor plates. The boundaries between these plates can be described as divergent, convergent or transform. At divergent boundaries plates are moving apart, at convergent they are moving together and are moving laterally past each other. Lithospheric plate is destroyed at convergent plate boundaries when one plate is subducted ...

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