【摘要】 回溯2018年12月至2019年11月期间广西及邻区出现的5次显著的地磁日变化预测指标异常，以及期间异常阈值线附近发生的多次M_S≥4.2地震，探究广西及邻区地磁日变化预测指标异常和显著地震的关系，并尝试探讨地磁日变化预测指标在类似广西这种少震区的适用性。结果显示，广西及邻区出现的地磁加卸载响应比、逐日比和地磁低点位移异常与发生在异常阈值线附近的4.9级以上地震存在较好对应，地震“时空强”参数基本满足现行地磁预测指标的预测规则。考虑地磁观测台站密度和构造背景差异，地磁加卸载响应比和逐日比指标在广西及邻区的预测时间为12个月内，预测地点重点关注阈值线附近200±50 km的区域，存在1次地磁日变化预测指标异常对应多个地震和1个显著地震前出现多次地磁日变化预测指标异常的情况。更多还原

【Abstract】 From December 2018 to November 2019, there are five significant anomalies of prediction index of geomagnetic diurnal variation in Guangxi and its adjacent areas, and several earthquakes with Ms≥4.2 occurred near the threshold line of the prediction index anomaly. Its internal relationship is worth exploring. This paper study their relationship and discusses the applicability of these prediction index in less seismicity areas similar to Guangxi. The results show that the anomalies of geomagnetic load-unload response ratio, geomagnetic daily ratio and geomagnetic low-point displacement in Guangxi and its adjacent areas are well corresponding to earthquakes with Ms≥4.9 occurring near the anomaly threshold line recently. The seismic parameters of original time, epicenter and magnitude basically meet to the prediction rules of current geomagnetic prediction indexes. In consideration density of geomagnetic observation and tectonic background, it is reasonable to appropriate relax the prediction rules for weak seismic region in practice sometimes. The prediction time of geomagnetic loading-unloading response ratio and daily ratio index in Guangxi and its adjacent areas is within 12 months, and the prediction location focuses on the area 200±50 km near the threshold line. These phenomena of one abnormal prediction index of geomagnetic diurnal variation corresponding to several earthquakes and one significant earthquake corresponding to several abnormal prediction index of geomagnetic diurnal variation are existing.更多还原