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一、前言众所周知中国西部及毗邻地区,从1897年印度阿萨姆8.6级地震到1957年蒙古阿尔泰大震,这六十年内发生了一系列强烈地震,形成了中国西部地区地震活动高潮期,以后便进入了相对平静,甘肃河西地区正是在这个背景下发生了1927年古浪8级大震,1932年昌马7.5级大震,1954年山丹7(1/4)级地震和同年民勤7级大震。此后地震活动很快平静下来,近三十年来5级和5级以上地震都很少发生,既使在六十年代至七十年代,我国华北、西南大震频
I. Preface It is well known that in western China and its adjacent areas, a series of strong earthquakes occurred during the 60 years from the 1897 Assam of India in 1897 to the Altai earthquake in Mongolia in 1957, which formed the climax of the seismic activity in the western part of China. It entered into a relative calm. It is in this background that Gushu M8 earthquake occurred in 1927, Changchun M7.5 earthquake in 1932, 7 (1/4) magnitude earthquake in 1954 and same age people Qin 7 earthquake. Since then, the earthquakes have quickly calmed down. In the recent three decades, earthquakes of magnitude 5 and above rarely occurred. Even in the 1960s and 1970s, the frequency of major earthquakes in North China and Southwest China