临汾地震台地电阻率异常变化特征与盆地内地震关系分析

Analysis on relationship between variation characteristics of earth resistivity anomaly and earthquakes in basin

主要以临汾盆地及周边地区近20年来所发生的6次4.5级以上地震为例,通过对这几次地震前临汾地震台地电阻率观测数据的分析,总结出临汾地震台地电阻率对应中强地震的中短期异常变化特征,特别是盆地内发生的3次地震,每次震前两测向曲线均统一表现为各向异性的变化特征,为判定该地区的震情趋势提供了信度较高的依据。

Taking 6 earthquakes with magnitude above 4.5 occurred in Linfen basin and surrounding areas in recent 20 years for examples, and through observation data analysis of Linfen earth resistivity just before these earthquakes, the anomaly variation characteristics of Linfen earth resistivity with medium-short period corresponding to moderate-strong earthquakes are summarized in this paper. Especially, for 3 earthquakes happened in basin, both curves with two direction measurement display anisotropic variation characteristics before each earthquake. This provides evidence with high reliabilities for judging earthquake situation trend in this area.