【摘要】 以研究区的构造块体为背景,对山西大同1989年MS6.1、1991年MS5.8及1991年忻州MS5.1地震前地壳形变、地下流体、电磁及测震学科的异常图像进行分析,明确了各项异常在时间、空间上的关联、组合及其与地震过程的内在联系。得出,山西北部发生MS5.0以上中强地震前的异常时间达3 a左右,震中区会形成比较明显的闭锁区域或空段,前兆异常与小震活动异常的起始时间和空间分布是比较一致的。更多还原

【Abstract】 Taking tectonic block of the investigated region as background,the abnormal imagine of crustal deformation,underground fluid,electromagnetism and earthquake observation before the 1989 Datong earthquake of M6.1,the 1991 Datong earthquake of M 5.8 and the 1991 Xinzhou earthquake of M5.1 are analyzed.The relation and combination of each item of anomalies in time and space are figured out and the inner link of them to the seismic process are confirmed.The results show that the abnormal time before medium-strong earthquakes of M5.0 in north Shanxi is nearly three years,with quite obvious locked area or empty segment formed in epicenter area.The starting time and space distribution of precursor anomaly are quite accordant the anomaly of small earthquake activity.更多还原