the upper mantle below the earth's crust is known as the
Mantle (geology) Two main zones are distinguished in the upper mantle: the inner asthenosphere composed of plastic flowing rock of varying thickness, on average about 200 km (120 mi) thick,[16] and the lowermost part of the lithosphere composed of rigid rock about 50 to 120 km (31 to 75 mi) thick.[17] A thin crust, the upper part of the lithosphere, surrounds the mantle and is about 5 to 75 km (3.1 to 46.6 mi) thick.[18] Recent analysis of hydrous ringwoodite from the mantle suggests that there is between one[19] and three[20] times as much water in the transition zone between the lower and upper mantle than in all the world's oceans combined.[21]
Crust (geology) The continental crust has an average composition similar to that of andesite.[9] The most abundant minerals in Earth's continental crust are feldspars, which make up about 41% of the crust by weight, followed by quartz at 12%, and pyroxenes at 11%.[10] Continental crust is enriched in incompatible elements compared to the basaltic ocean crust and much enriched compared to the underlying mantle. Although the continental crust comprises only about 0.6 weight percent of the silicate on Earth, it contains 20% to 70% of the incompatible elements.