It is composed of rocks, mostly, and the upper mantle. The name 'lithosphere' comes from the Greek 'lithos', meaning rocky, and 'sphaeros', meaning sphere.
The lithosphere is the earth's outermost layer, composed of rocks and the upper mantle.
The parts of the crust that contain the world’s oceans are very different from the parts that form the continents. The continental crust is 10-70 km thick, while oceanic crust averages only 5-7 km in thickness.
The lithosphere is broken up into plates that the underlying mantle supports. When new crust is formed, it is formed when plates are moving away from each other. When plates collide, old plates are recycled into the mantle.
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