That the cyclical change of the shape of the mantle produces potential energy force in earth's crust results in crustal movement.

地幔圈形状周期性变化使地壳产生势能（位能）力导致地壳运动。

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The Earth's crust being molten and differentiated from the mantle has long been the foundation of geology and also has been taken as the fundamental cause of plate movement.

地壳从地幔中熔融出来是地质学立论的基础，也是板块构造运动的基本原因。

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"The recent earthquakes in Manchester and Italy have highlighted our need to better understand the movement of the Earth's crust in England, " said Dr Matt King of Newcastle University's School of Civil Engineering and Geosciences.

BBC: Satellite technology aids quake research