2019年10月12日广西北流-广东化州5.2级地震特征分析

Characteristics of Huazhou-Beiliu MS 5.2 Earthquake on October 12^th,2019

2019年10月12日,在广东省化州市与广西壮族自治区北流市交界地区发生5.2级地震,这是华南地区进入20世纪以来第Ⅴ活跃幕之后发生的第3次5级以上地震,也是粤桂交界地区第Ⅴ活跃幕以来第2次5级以上地震。此地震发生北西向巴马-博白-茂名断裂带的陆川-高州段上,属6级潜在震源区,基本烈度为Ⅵ度区。震中区在历史上属于少震弱震区,但从2014年以来,地震活动出现间歇性增强,多项地球物理观测数据也时有异常表现。广东省地震局在2018年度地震会商时把此区域确定为2019年度地震危险重点注意地区。10月12日5.2级地震的发生验证了年度地震危险重点注意地区的判定,为以后的地震预测工作提供了可参考的分析依据。

On October 12^th,2019,an Ms5.2 earthquake occurred at the junction of Huazhou City,Guangdong Province and Beiliu City,Guangxi Zhuang Autonomous Region,which is the third earthquake with Ms≥5 after the South China region entered the second active period and the fifth active scene,and is also the second earthquake with Ms≥5 since the fifth active scene in the border area between Guangdong and Guangxi.This earthquake occurred on the Luchuan-Gaozhou section of the Bama-Bobai-Maoming fault zone in the northwest direction,which is a potential source of magnitude 6 with a basic intensity ofⅥ.The epicentral area is a weak earthquake areahistorically,but since 2014,seismic activity has increased intermittently,and many geophysical observations also have anomalous performance.The Guangdong earthquake agency identified the area as a keyearthquake hazard area in 2019in the annual earthquake conference(2018).The occurrence of the Ms5.2 earthquake has verified the judgment of the key earthquake hazard areaof the year and provided a reference for the future earthquake prediction.