四川西部发生7级大震危险性分析

Risk Analysis of M7.0 Earthquake Occurring in the West of Sichuan

四川西部地处青藏高原东部，是我国强震多发地区之一。1976年松潘7．2级大震后至今已近20年无大震发生，超过本世纪发生7级大震的最长间隔时间，加之川滇7级大震有对迁特点，1996年2月3日丽江7．0级大震后，四川发生大震的危险更为增大。另外，结合其它条件分析，认为四川西部地区，尤其是马边与冕宁二地未来1—3年内有发震危险。

The west of Sichuang situated in the east of Qing-Zang plateau is one of the regions where strong earthquakes often occur. But any strong earthquake has not occurred near 20 years since the 1976 M7. 6 Songpan earthquake. The interval time has surpassed the longest interval time between adjacent strong earthquakes in the century. And there is the feature that M7.0 earthquakes migrate alternately between Sichuan and Yunnan. The risk that any strong earthquake can occur in Sichuan increases further after the Feb. 3, 1996 M7. 0 Lijiang earthquake. Combining analysis of other factors, in addition, we consided that there is seismogenic risk in the future 1～3 years in the west of Sichuan, particularly the Mabian and the Mianning regions.