印度—澳大利亚板块边界带强震活动与中国大陆西部强震活动的相关性研究

2001年以来全球8级地震呈现新的活跃态势, 7.5级以上强震在空间上呈优势分布, 强震相对集中在西太平洋地震带和欧亚地震带, 印度—澳大利亚板块的汇聚边界带上尤为突出。 2009年全球发生20次7级以上强震, 其中有15次发生在印度—澳大利亚板块, 近期仍具有延续全球强震活动优势空间分布。 本文在以往关于印度—澳大利亚板块运动方式以及相关地震活动研究基础上, 将印度—澳大利亚板块分为印度亚板块和澳大利亚板块, 依据强震应变释放资料分析中国大陆西部、 印度板块边界和澳大利亚板块边界之间强震活动可能的相关性。 结果表明, 中国大陆西部地区与印度板块边界的强震活动有较好的相关性, 印度板块边界与澳大利亚板块边界活动也有一定的相关性。 1914—1993年时段的中国大陆西部地区5个完整强震释放时段与印度板块地震活动表现出很强的相关性, 且中国大陆西部地区强震活动相对印度板块边界地区滞后0~5年, 这对于中国大陆地区强震趋势跟踪具有一定的参考意义。

Possible Impacts of Seismic Activity in Indian-Australian plate on the Western China Continent

Earthquakes with magnitude greater than or equal 8.0 has being active in the global world since 2001. From the distribution of M_S≥7.5 earthquakes, these strong earthquakes are relatively concentrated in the western Pacific Seismic Belt and the Eurasian Seismic Zone, especially the boundary belt of convergence of India-Australian plate. Under this background, there were two earthquake of M_S≥8.0 occurred in western China. During 2009 there were more than 20 earthquakes of M_S≥7.0 in the whole world (as up to November 15), of which 15 still occurred in the Indian-Australian plate. So the spatial distribution of strong earthquake worldwide is still in the case as before. In this paper, based on the movement pattern of the India-Australia plate and related seismic research, using strain releases of strong earthquakes, we analyzed the possible impacts of each other between the seismic activity in western China, Indian plate and the Australian plate. The results show that there is a good correlation between the seismicity in western China and those in the boundary of Indian plate. From1914 to 1993, five complete release time periods of strong earthquakes in western China have better correlations between the seismicity in western China and those in the boundary of Indian plate. And comparatively speaking, strong earthquake activities in western China is relatively impeded by a lag of 0~5 year, which maybe useful for tracking the trend of strong earthquakes in the China continent.