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地震对当地地质地貌的塑造具有很大的作用,通过研究阿拉斯加中南部的地震特征有助于进一步了解中南阿拉斯加的地质构造。在梳理重要地震及其相关知识的前提下,对阿拉斯加中南部地区的地震特征进行了分析。指出:(1)中南阿拉斯加的地震频繁且常常能量巨大,太平洋板块俯冲及其向形成阿拉斯加南部的地体上施加的压力是促成中南阿拉斯加发生地震的原因;(2)发生在1964年的美好星期五大地震的震中位于威廉王子湾北部的阿奈奎克湾东岸的地下,瓦尔迪兹以西大约40英里的地方,地面大约12英里以下的浅源区,这次地震的震级为里氏9.2级。在这次大地震中,不同的位置发生了不同的沉降和隆升,这种规模的地震在中南阿拉斯加平均大约每600~950a会发生一次;(3)德奈利断层是个平移断层,断层的一盘相对于另一盘做平移移动。发生在2002年的德奈利断层大地震记录到的震级为里氏7.9级,在门塔斯塔湖和帕克森之间的断层附近,地面水平位移达到最大,为29英尺。此次地震只发生在3英里多一点的深度,是北美洲对地面破坏最严重的地震,这种规模的地震再经过600a的扭力积聚后还会发生。
The earthquake plays an important role in shaping the local geology and geomorphology. It is helpful to further understand the geological structure of Alaska in central and southern China by studying the seismic characteristics in south-central Alaska. Based on the analysis of major earthquakes and their related knowledge, the seismic characteristics in central-southern Alaska are analyzed. Points out that: (1) the frequent and often massive energy quakes in Central and Southern Alaska have caused the earthquake in Central and Southern Alaska, caused by the Pacific plate subduction and the pressure exerted on the land forming southern Alaska; (2) the fantastic Friday that occurred in 1964 The epicenter of the devastating earthquake lies on the eastern bank of the Gulf of Aynique in northern Prince William Bay, about 40 miles west of Valdez and about 12 miles below the surface. The magnitude of the earthquake was 9.2 on the Richter scale . During this large earthquake, different subsidence and uplift occurred in different places. This type of earthquake occurs once every 600 to 950 years in Central South Alaska. (3) The Denali fault is a translatory fault and a fault One plate moves in translation relative to the other. The magni- tude recorded in the de Nalei earthquake in 2002 was 7.9 on the Richter Scale, and the ground level reached a maximum of 29 feet near the fault between Lake Manta and Paxson. The earthquake occurred only a little more than three miles and was the most devastating earthquakes in North America on the ground, and earthquakes of this magnitude took place again after 600 years of torque build-up.