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本文对比了1918—1976年发生的中国华北地震和日本列岛及其附近的较大地震,发现二者有比较好的对应关系。一般是,日本海沟先发生7—8级大地震序列,其后日本海西部发生h≥300公里的深源地震,最后我国华北地区发生M≥6的强烈地震。对1918年以来的十四个活动期进行了统计分析,得到复相关系数R=0.82,能够在很高的显著性水平上通过F检验。日本海沟地震约有30年左右的重复期。从1926年至今,日本海沟地震的活动中心向北漂移了3°—4°,与此同时,我国华北地震活动也以相同速率向北迁移。地震活动在时间和强度上的相关性、震中的相关迁移以及震源机制等方面的事实都表明,我国华北强烈地震可能受日本海沟板块俯冲运动的控制,上地幔中可能存在着某种物质流动的通道。
This article compares the earthquakes in North China during 1918-1976 with those in Japan and the nearby islands in Japan and finds that there is a good correspondence between the two. In general, the series of earthquakes of magnitude 7-8 preceded the trough in Japan, followed by a deep-source earthquake of h ≥ 300 km in the western part of Japan Sea. Finally, a strong earthquake with M ≥ 6 occurred in North China. A statistical analysis of the fourteen active periods since 1918 resulted in a complex correlation coefficient of R = 0.82, which passed the F-test at a high level of significance. Japan trench earthquake about 30 years of repetition. Since 1926, the active center of the Japan Trench Earthquake has drifted 3 ° -4 ° to the north. At the same time, the seismic activity in North China has migrated to the north at the same rate. The correlation between seismicity in terms of time and intensity, the related migration in epicenters, and the focal mechanism suggest that strong earthquakes in North China may be controlled by the subduction of the Japanese trench plateau, and some material flow may exist in the upper mantle aisle.