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弄清楚全球背景下的区域地质特征,有利于理解阿拉斯加复杂的地质现象。在梳理地质体形成的基础上,对阿拉斯加中南部地区的地质体、断层以及地壳情况进行说明。指出:中南阿拉斯加绝大部分的地质体起源于遥远南方的火山岛弧及其侵蚀沉积物。在中南阿拉斯加,最古老的地质体位于北部更靠近北美克拉通的地方。通常情况下,距克拉通越远,地质体的地质年龄就会越年轻。威廉王子地质体和亚库塔特地质体是本地区最年轻的地质体;阿拉斯加南部地区地断层有许多种成因。在古俯冲区中、地质体内、裂谷带沿线以及两个板块侧面相对运动滑擦的地区,皆可发现断层;中南阿拉斯加的地质情况相当复杂。
Understanding the regional geological features in a global context is conducive to understanding the complex geological phenomena in Alaska. Based on the formation of geologic bodies, the geological bodies, faults and the crust in the central-southern Alaska are described. Pointed out that most of the geological bodies in Central and Southern Alaska originate from volcanic island arcs and their erosion sediments in the far south. In Central South Alaska, the oldest geological body is located in the North closer to the North American craton. In general, the farther away from craton, the geologic body will be geologically younger. The Prince William and Yakutti geologic bodies are the youngest geologic bodies in the region; there are many causes of faults in southern Alaska. Faults can be found in the area of ancient subduction areas, in the geological body, along the rift zone and in the areas where the relative motion between the two plates is sliding. The geological situation in Alaska, Central China is rather complicated.