综合定点前兆异常推测地震危险区域的一种途径  

One Approach for Predicting Earthquake Risk Area from Synthesizing Fixed-point Precursory Anomalies

作　　者：张希[1] 李瑞莎[1] 唐红涛[1] 贾鹏[1] 

机构地区：[1]中国地震局第二监测中心,陕西西安710054

出　　处：《地震研究》2012年第1期1-5,157,共5页Journal of Seismological Research

基　　金：中国地震局地震科技星火计划项目"青藏块体东北缘前兆系统结构分析与异常识别"(XH12072);陕西省科学技术发展计划项目"汾渭断裂带地壳运动的非均匀负位错模拟与应变积累研究"(2011JM5016)联合资助

摘　　要：1998年张北6.2级地震前,山西、河北及其附近地区出现的定点形变、流体前兆异常,具有随时间推移从震区外围大范围区域向震区附近迁移、集中的趋势特性。通过构建异常信号传播函数,借助网格搜索—拟牛顿最小二乘法反演汇聚区域即推测可能的地震危险区,所得汇聚区域边缘距实际震中仅25～51km、汇聚时刻与发震时刻仅差数天,且震前中短期阶段汇聚速度加快。Precursory anomalies of deformation and fluid measured in fixed-point appear the trend features of moving and concentrating from distance areas to the near of seismic area before the Zhangbei MS6.2 earthquake in 1998.Constructing abnormal signal spreading function,and using grid searching-quasi Newton least square method,we inverse the converged region of precursory anomalies which is the predicting possible risk region.The result shows that the distance between the margin of calculated converged region and the real epicenter is only 25-51 km.The difference between the converging time and the original time is only several days.Moreover,the converging rate speeds up at the middle-short term before Zhangbei MS6.2 earthquake.

关 键 词：定点前兆异常 传播函数 反演 地震危险区 

分 类 号：P315.72[天文地球—地震学]