1573年甘肃岷县地震史料考证与发震构造探讨

Textual Reasearch on the Historical Data of the 1573 AD Minxian Earthquake in Gansu Province and Disscussion on Its Seismogenic Structure

通过对1573年甘肃岷县地震的历史资料考证和发震构造的综合研究表明：在1573年岷县地震中遭受破坏最为严重的地区位于如今的岷县县城一带（当时为岷州府所在地）。综合各种资料确定1573年甘肃岷县地震震级为6％，极震区烈度为Ⅷ-Ⅸ度，震中位于北纬34．40，东经104．0°，震中精度为2类，震中位置偏差小于或等于25km。该地区构造上位于东昆仑断裂带和西秦岭北缘断裂带的应变传递和构造转换的中间过渡区，其中的临潭-宕昌断裂带活动特性差异明显，只有部分地段表现出全新世活动特征，地震极震区一带分布有不同程度的滑坡和基岩崩塌等。综合分析认为，临潭-宕昌断裂带的岷县-宕昌段是甘肃岷县1573年6％级地震的发震构造。

According to the detail research of the historical earthquake records and causative structure on the Minxian M6Y2 earthquake, we have found that the most grievous disaster area nearby Minxian city（Minzhou county at that time）. So, we have concluded that the extremely seismic area of the 1573 AD Minxian M61/2 earthquake located in Minxian city, the intensity is Ⅷ-Ⅸ, the epicenter is 34.4° N, 104.0°E, its precision is Ⅱ and the error of the place is less than and equal to 25kin. Tectonically, this area lie tothe transition region of stress transfer and structural transform between the east Kunlun fault and the northern segment of west Qinling fault. Activity of the Lintan-Dangchang fault zone has obvious difference, only the partial segment put up the activity of Holocene. There are different size coasts and rock breakdown at the extremely seismic area. By general analysis, we consider that the Minxian-Dangchang segment of the Lintan-Dangchang fault is causative structure of the 1573 AD Minxian M61/2 earthquake, in Gansu Province.