2019年广西北流—广东化州MS 5.2地震前活动性参数异常分析

2019年10月12日，广西北流—广东化州交界发生M_S 5.2地震，选取广西北流—广东化州区域2010年1月1日—2019年12月31日M_L≥2.0地震目录，对震前地震活动性参数进行时空扫描，并进行地震空区分析，发现部分地震活动性参数异常，且震前存在孕震空区。分析结果如下：震前b值时间扫描曲线长期位于均值线之上，持续时间一年以上；b、C、D值空间扫描均存在异常，其中震前b值异常范围为1.0—2.0，C值异常范围为0.04—0.32，D值异常范围为0.01—0.09；2016年4月至2019年9月，震中附近出现孕震空区，后在空区边缘发生此次M_S 5.2地震。

Anomaly analysis of pre-earthquake activity parameters of Guangxi Beiliu-Guangdong Huazhou MS 5.2 earthquake in 2019

An M_S 5.2 earthquake occurred at the border of Beiliu in Guangxi Province and Huazhou in Guangdong Province on October 12, 2019. The M_L ≥ 2.0 earthquake catalog of Guangxi Beiliu-Guangdong Huazhou from January 1, 2010 to December 31, 2019, was selected to carry out spatio-temporal scanning of seismicity parameters before the earthquake and conduct a seismic gap analysis. Some seismicity anomalies were found and there were seismogenic gaps before the earthquake. The analysis results are as follows:the time scan curve of b-value before the earthquake is above the mean value for a long time, lasting for more than one year; There were anomalies in the spatial scanning of b, C and D values. Before the earthquake, the abnormal ranges of b-value, C-value and D-value were 1.0-2.0, 0.04-0.32 and 0.01-0.09, respectively. From April 2016 to September 2019, there was a seismogenic gap near the epicenter and the M_S 5.2 earthquake occurred at the edge of the gap.