【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。更多还原

【Abstract】 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.更多还原