Lithosphere is the outer covering or layer of a planet. We can also think of lithosphere as the outer surface of Earth where we live and where processes relevant to us takes place. In reality, lithosphere is composed of two parts: crust and topmost layer of mantle (which stays solid). These layers are underlain by hotter part of our planet (known as asthenosphere), including the mantle and the core. Heat conduction takes place through the lithosphere, while the underlying layers experience heat convection. The thickness of lithosphere ranges from 80-120 km. Lithosphere consists of both continental and oceanic lithosphere and is generally divided into a number of tectonic plates. The motion of these plates or plate tectonics results in the formation of mountains, earthquakes, volcanoes, etc.
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