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| gen. |
petrosphere |
| agric. |
earth's crust; terrestrial crust |
| desert. |
crust of earth |
| el. |
earth's mantel |
| eng.geol. |
crust of the earth; earth’s crust |
| environ. |
earth's crust The outer layers of the Earth's structure, varying between 6 and 48 km in thickness, and comprising all the material above the Mohorovicic Discontinuity (a seismic discontinuity occurring between the crust of the earth and the underlying mantle; the discontinuity occurs at an average depth of 35 km below the continents and at about 10 km below the oceans). The earlier idea of a cool solid skin overlaying a hot molten interior has now been replaced by a concept of a crust composed of two shells: an inner basic unit composed of sima (oceanic crust) and an outer granitic unit composed of sial (continental crust) (地球结构的外层，厚度为6公尺至48公尺，包含莫霍(洛维奇)不连续面(一个引起地震的不连续面，出现在地壳及其下的地幔之间；这不连续面出现在陆地下平均35公里和海洋下大约10公里处)以上的所有物质。 以前认为一个冷却坚固的表层覆盖着热熔融内部的想法，现在已被地壳是由两层外壳组成的概念所取代，一个是硅镁组成的内部基本单元(大洋地壳)，一个是由硅铝组成的外部花岗石单元(大陆地壳)。) |
| geol. |
shell |
| hydroel.st. |
crust; earth crust |
| met. |
lithosphere |
| space |
earth shell |
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地壳根据地震波速度、密度和组成划分出来的地球最外面的壳层。其下为莫霍不连续面，厚度〈深度〉平均为 30hn,主要由结晶岩组成。大陆地壳又以康拉德不连续面分出上面的硅铝层和下面的硅镁层, 大洋地壳以广泛发育硅镁层为特点。它占有地球总容积的1%弱 dìqiào | |
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| expl. |
crust |
