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本文初步研究了全球某些岛弧海沟构造系统中浅源强震的震中位置和地球自转速率变化的相关关系(简称ER关系)。汤加—克马德克、印尼爪哇、日本和阿拉斯加—阿留申等的岛弧海沟地段的ER关系表明,在海沟及其附近的重力负异常地区内,地震多在地球自转加快的年份中发生;而在岛弧及其附近的重力正异常地区内,地震主要发生在自转相对减慢的年份中。这种特征可能不仅和海洋与大陆板块汇聚边界的岛弧海沟上的基本应力状态有关,而且与自转速率不均匀产生的附加应力状态有关。
In this paper, the relationship between the epicenter position of shallow-strong earthquakes and the change of Earth’s rotation rate in some island arc trench structural systems in the world (ER relationship for short) has been preliminary studied. The ER relationship between Tonga-Kermadec, Indonesia, Java, Japan and Alaska-Aleutian shows that in the trenches and the negative gravity anomalies near the earthquakes, earthquakes happen frequently in the years when the Earth rotates autonomously. In the area where the gravity is anomalous around the island arc and its vicinity, the earthquakes mainly occur in the relatively slow rotation years. This feature may be related not only to the fundamental stress states on island arc trenches along the convergence boundary of the ocean and continental plates, but also to the additional stress states resulting from the non-uniform rate of rotation.