Plate Tectonics

板块构造

The rocky mountains seem high and solidly fixed, but their height is a tiny fraction of the Earth's radius, and they sit atop a likewise thin solid crust on the Earth. Evidence has mounted that sections or "plates" of this solid crust move with time and have made dramatic movements during the time that life has existed on the Earth.

罗基山脉看起来高大而稳固，但其高度只是地球半径的极小一部分，它们位于地球同样薄而坚固的地壳之上。证据表明，这一固态地壳的某些部分或‘板块’随时间移动，并且在地球上有生命存在的这段时间内发生了显著的移动。

Below is a set of sketches of continent outlines modeled after the USGS site, giving a view of the postulated movements of the continental plates. A major work called The Dyamic Earth is available through the U.S. Geological Survey : http://pubs.usgs.gov/gip/dynamic/dynamic.html . The names Pangaea for the supercontinent and Laurasia and Gondwanaland for the stage after breakup date back to the time of Wegener.

以下是一些根据USGS网站绘制的大陆轮廓图，展示了大陆板块的假想运动。通过美国地质调查局可获得一部名为《动态地球》的著作：http://pubs.usgs.gov/gip/dynamic/dynamic.html。 Pangaea 作为超大陆的名称，以及 Laurasia 和 Gondwanaland 作为分裂后的阶段，其名称可追溯到 Wegener 的时代。

Developing the Picture of Plate Tectonics

板块构造的图像

The idea of plate tectonics was resisted strongly when it was first suggested by Frank B. Taylor in 1910. But it had a persistent advocate in Alfred Wegener who argued in favor of it from 1912 until his death in 1930. Wegener pointed to the similarity of separated coastlines and the presence of similar fossils in coastal areas that are presently widely separated.

当弗兰克·B·泰勒于1910年首次提出板块构造理论时，这一观点遭到强烈反对。但阿尔弗雷德·韦格纳则是坚定的倡导者，他从1912年一直坚持支持这一理论，直到1930年去世。韦格纳指出，分离的海岸线具有相似性，且目前相距很远的沿海地区存在相似的化石。

It was not until the 1960s that plate tectonics began to be widely accepted. Geologist Arthur Holmes proposed the existence of convection cells in the upper mantle with hot material rising, carrying the thin crustal skin with it parallel to the Earth's surface and then sinking as it cooled. The model of plate movement was reinforced by the study of magnetic alignment of rock and the study of the dynamics of the ocean floor.

直到20世纪60年代，板块构造理论才开始被广泛接受。地质学家阿瑟·霍尔姆斯提出了上地幔中存在对流细胞的假说，热物质上升，携带薄的地壳表层平行于地球表面移动，随后冷却下沉。该模型通过岩石磁性对齐的研究和海底动力学的研究得到了加强。