利用断层活动协调比方法分析云南现今地壳应变积累  

Analysis of Current Crustal Strain Accumulation in Yunnan with the Fault Motion Coordination Ratio Method

作　　者：徐东卓[1] 塔拉[1] 罗三明[1] 朱文武[1] 王世进[1] 尹海权[1] XU Dongzhuo;TA La;LUO Sanming;ZHU Wenwu;WANG Shijin;YIN Haiquan(The First Monitoring and Application Center, CEA, Tianjin 300180, China)

机构地区：[1]中国地震局第一监测中心,天津300180

出　　处：《地震工程学报》2021年第1期43-49,共7页China Earthquake Engineering Journal

基　　金：地震科技星火计划项目(XH20077Y);科技部基础性工作项目(2015FY210400)。

摘　　要：断层活动协调比方法在分析云南地区的地壳应变积累上具有适用性。利用区域11处跨断层流动监测场地的三十余年观测资料,首先计算跨断层场地的三维活动量,进而得出场地的断层活动协调比参数,结果显示:(1)丽江、永胜、剑川、石屏、建水场地在对应6~7级地震上,历史映震效果良好;云南地区近期存在异常的跨断层监测场地有剑川、石屏和建水场地,存在应变积累、断层活动出现异常的断裂有剑川断裂和石屏-建水断裂;(2)结合跨断层原始观测数据和三维活动量时序曲线,综合认为云南地区地壳形变异常区域分布在滇西北地区的剑川、下关和永胜以及滇中地区的峨山、石屏和建水附近;(3)结合地震活动性资料,综合认为四川九寨沟7.0级地震后,南北地震带南段应力可能会加速积累,应重点关注云南地区的中强震危险性。The fault motion coordination ratio method can be applied to analyze the crustal strain accumulation in Yunnan area.Based on the observation data of 11 cross-fault flow monitoring sites for more than 30 years,the three-dimensional activities on the sites were first calculated,and then the coordination ratio parameters of fault activity were obtained.The results showed that:(1)The sites of Lijiang,Yongsheng,Jianchuan,Shiping,and Jianshui have good reflecting effect to historical earthquakes with magnitude 6-7.There are anomalies in the sites of Jianchuan,Shiping,and Jianshui recently,and the strain accumulation and abnormal fault activities are show along the Jianchuan and Shiping-Jianshui faults;(2)Combined with the original cross-fault observation data and the three-dimensional activity time series curve,it is considered that the crustal deformation anomalies are distributed in Jianchuan,Xiaguan,and Yongsheng of northwestern Yunnan,and near Eshan,Shiping,and Jianshui of central Yunnan;(3)It is considered that after the Jiuzhaigou M7.0 earthquake in Sichuan Province,the stress accumulation in southern part of the North-South seismic belt may be accelerated,so more attention should be paid to the risk of moderate and strong earthquakes in Yunnan.

关 键 词：云南地区 跨断层监测 断层活动协调比 应变积累 

分 类 号：P315[天文地球—地震学]