青藏高原西北于田地区强震后地震迁移图像与活动构造关系讨论

A Study on Seismic Migration and Active Tectonics after Earthquakes in the Northwest Region of the Tibetan Plateau

本文通过整理和分析青藏高原西北于田地区强震后,地震迁移的空间分布,迁移特征,同时整理和分析与迁移地震相关的青藏高原主要活动构造的结构和地震活动,分析两者之间的关系。得到以下结论：1迁移地震空间分布具有不均匀性,主要分布在活动地块边界,受大型活动构造带控制;2迁移路径主要有三条,第二条路径更为重要,主要沿着昆仑山脉向唐古拉山、巴颜喀拉山及阿尼玛卿山,在若尔盖盆地东北侧折向东南,向岷山、龙门山迁移;3未来5年内在青藏高原西北于田地区可能发生1~2次6.5级左右地震,在龙门山南段等地震空区内可能发生迁移强地震;41900年以来发生的地震沿先前存在的地震空区分布。

Based on spatial distribution and characteristics of seismic migration after the earthquakes in the northwest region of the the Tibet plateau, we discussed the main active tectonic structures and seismic activity, which related to seismic migration. By analyzing the relationship between active tectonics and seismic activity, the following conclusion- sareobtained： （1） Migration earthquakes are unevenly distributed in the border of active blocks, controlled by the large active tectonic zones; （2） There are three migration paths, dominated by the second path; （3） Within the next five years in the west area of the Altun fault zone, there will be one or two earthquakes of magnitude 6.5; （4） Earthquakes hap- pened after 1900 are mainly distributed along the empty areas; （5） Within the next three to six months, strong migration earthquakes may occur in seismic empty areas, such as the south section of Longmenshan.