巴颜喀拉块体周缘几次强震对甘肃地区地震形势的影响  

Effect on Seismic Situation of Gansu Region from Several Strong Earthquakes around the Bayan Har Block

作　　者：杨兴悦 陈连旺[2] 杨立明[3] 李玉江[2] 

机构地区：[1]甘肃省地震局天水中心地震台,甘肃天水741020 [2]中国地震局地壳应力研究所(地壳动力学重点实验室),北京100085 [3]中国地震局兰州地震研究所,甘肃兰州730000

出　　处：《地震》2013年第3期77-89,共13页Earthquake

基　　金：国家科技支撑计划子专题(2006BAC01B03-04-05)资助

摘　　要：以青藏高原为目标,采用黏弹性体本构关系建立3D有限元模型,模拟了在印度板块持续向北推进、挤压下,巴颜喀拉块体周缘强震对邻近地区的影响。通过降低强震发生位置处单元弹性模量的方法模拟了2001年昆仑山口西MS8.1、2008年汶川MS8.0、2010年玉树MS7.1地震,计算了发生这3次MS7.0以上强震后50年内每5年的黏弹性调整过程,讨论了3次强震对祁连地震带及甘东南地区地震形势的影响,尝试开展依据区域应力调整特征判定未来强震危险区的探索试验。In this paper,we used the viscoelastic constitutive relation to build the 3D finite element model,and to simulate the effect in the neighborhood of strong earthquakes around Bayan Har Block,which is in the everlasting northward propulsion of the Indian plate.By reducing the element elastic modulus in the earthquake location to simulate the Kunlun Mountain Pass MS8.1 earthquake in 2001,the Wenchuan MS8.0 earthquake in 2008 and the Yushu MS7.1 earthquake in 2010,we calculated the process of the adjustment of the viscoelasticity of the coseismic equivalent stress in the next 50 years caused by three strong earthquakes,And we discussed the effect on seismic situation of the Qilian seismic belt and the southeast of Gansu Province from 3 strong earthquakes around Bayan Har Block,trying to do the exploratory experiment of judging risk area based on the characteristics of the adjustment of regional stress.The preliminary conclusion is that the adjacent zone of the southeast of Gansu province and Qinghai province and the adjacent zone of Gansu province and Qinghai province and Sichuan province are the risk areas of strong earthquakes.

关 键 词：巴颜喀拉块体 黏弹性有限元模型 强震 甘肃地区 

分 类 号：P315.7[天文地球—地震学]