对143年甘谷西7级地震史料的新见解

A New Opinion about the West of Gangu M7.0 Earthquake in 143 A.D. in Gansu Province

摘要:

根据地震历史资料的考证分析,143年甘谷西地震可能由2次地震组成,其中陇西、汉阳(今甘谷)、武都三郡地震有感区为一次地震,称为南区;张掖、武威、北地(今吴忠)三郡地震有感区为另一次主震,称为北区。南区地震震中大致位于甘谷西,与原定震中位置大体相当,仍称为甘谷西地震,震级达714级左右,震中烈度约Ⅸ~Ⅹ度,发震构造为西秦岭北缘断裂带中段;北区的143年地震震中位于武威以东的腾格里沙漠边缘,震级达712级左右,震中烈度约Ⅹ度,推测其发震构造为祁连山-河西走廊活动断裂系东端的主干活动断裂之一。

Abstract:

According to the textual analysis of historical references, the earthquake of west Gangu in 143 A.D. can be divided into two main earthquakes. One earthquake feeling area include Longxi, Hanyang（now Gangu county） and Wudu counties is called south area. Another earthquake feeling area include Zhangye, Wuwei and Beidi（now Wuzhong city） counties is called north area. The earthquake epicenter of the south area is located at west of Gangu county, where con- sistence with the initial epicenter from by the earthquake catalogs, so the event can be called west Gangu earthquake. It＇s magnitude is about 71/4, and the intensity is about nine to ten, the causative structure is the middle segment of north margin active fault zone of Western Qinling. The ep- icenter of the north area is located at east of Wuwei, near the edge of Tenggeli desert. It＇s magnitude is about 71/2, the intensity is about ten, and the causative structure may be one of main fault zones in the east segment of Qilianshan-Hexi Corridor active fault system.