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mantle
The main bulk of a planet or large moon, lying between the crust and the core and differing in composition from both. Earth's mantle extends from about 7 km (beneath the continents) or 30 km (beneath the oceans) to 2,900 km below the surface. It makes up 84 percent of the Earth by volume and 67 percent by mass, and consists of silica, plus iron-, magnesium-, and other metal-rich minerals. The Gutenberg discontinuity separates the Earth's mantle from the outer core; the Mohorovicic discontinuity separates the uppermost portion of the mantle from the crust.
The hot plastic asthenosphere, part upper mantle and lower crust, separates the more brittle crust-mantle lithosphere above from the mesosphere below. The more solid mesosphere, located below the asthenosphere, includes part of the upper and all of the lower mantle.
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