中强地震形变前兆异常时空分布综述

以形变观测资料为基础, 对地球物理场区域形变测量和定点形变测量资料中的震前异常现象的时空分布特征进行了统计分析, 得到以下认识: 对于大范围的地球物理场区域形变, 异常发生时间较早, 范围相对较小, 适合于中长期地点的判定; 定点形变观测, 异常发生距发震时间较近, 但范围分布则较广泛, 适合于短期地震的预测, 发震地点需要结合大范围的区域形变测量资料来判断。 本工作对认识前兆异常现象的时空分布特征和加强实际预报效能都有积极的意义。

A Review of Temporal-spatial Distribution of Precursory Deformation Anomalies before Moderate to Strong Earthquakes

Based on crustal deformation observations, we counted and analyzed space-time distribution characteristics recorded by regional deformation of geophysical field and fix-site deformation observations. The results show that the anomalies in regional deformation of geophysical field occurred early and the anomaly range is narrow, which is more suitable for estimating the long-term location of future earthquake occurrence. For the fix-site deformation observations, the occurrence of precursory anomalies are usually close to earthquakes and the anomaly locations distribute in a big range, which is suitable for short-term earthquake prediction with the location estimated by combining the regional deformation of geophysical field. This work has positive meaning on understanding the space-time distribution of precursory anomaly and improving the effectivity of earthquake prediction.