The middle crust and the lower crust is in the ductile field.

上地壳表现为脆性变形，中、下地壳为韧性的流动变形。

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The metallogenic source material comes from the upper mantle and the lower crust.

成矿物质来源于上地幔和下地壳。

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The crust is multilayered and there exists a low velocity layer in the lower crust.

地壳由多层介质组成，在下地壳中存在着低速层。

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There were servants to address one's every material need, dinner in white tie and lavish gowns, and rules designed to keep the upper crust on top and the lower classes in their place.

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And those estimates are of what mining companies have concrete plans to get at numbers that are significantly lower than the colossal quantities of reserves buried throughout the Earth's crust.

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As exotic-auto makers redefine what a superluxury car can be, their executives are attempting a delicate balancing act: maintaining the exclusive cachet of their upper-crust brands while pursuing new wealthy customers that lower-end luxury rivals are currently scooping up.

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