广西北流-广东化州5.2级地震前粤桂琼地区重力变化特征  

The Characteristics of Gravity Variations in Guangdong,Guangxi and Hainan Regions before the Beiliu-Huazhou MS 5.2 Earthquake in the Junction of Guangxi and Guangdong

作　　者：李盛[1] 胡久常[1] 廖桂金[2] 王志成[1] 江蕾[1] LI Sheng;HU Jiuchang;LIAO Guijin;WANG Zhicheng;JIANG Lei(Hainan Earthquake Agency,Haikou 570203,China;Guangdong Earthquake Agency,Guangzhou 510070,China)

机构地区：[1]海南省地震局,海口570203 [2]广东省地震局,广州510070

出　　处：《华南地震》2020年第2期50-59,共10页South China Journal of Seismology

基　　金：中国地震局震情跟踪定向工作任务(2019010202、2020010213);中国地震局监测、预报和科研三结合课题(3JH-201901038);中国地震局地震科技星火计划(XH21024Y)联合资助。

摘　　要：收集了粤桂琼地区4个台站的连续重力观测资料和雷琼地区的流动重力观测资料,研究了广西北流-广东化州5.2级地震前粤桂琼地区重力变化特征。其中连续重力观测资料的分析从重力扰动和重力M2波潮汐因子变化两个方面进行;流动重力观测资料的分析从重力场差分动态和累积动态变化两个方面进行。连续重力观测资料的研究表明震前粤桂琼地区连续重力观测资料无异常现象;雷琼地区流动重力观测资料的研究结果表明,广西北流-广东化州5.2级地震前,震中附近地区存在重力场变化异常,异常持续时间约2年,异常范围约100 km,异常量级约50x10^-8m·s^-2,地震发生于重力场变化的高梯度带上。This paper collected the continuous gravity observation data of 4 seismic stations in Guangdong,Guangxi and Hainan,and mobile gravity observation data in Leizhou-Hainan area,and studied the characteristics of gravity changes in the Guangdong,Guangxi and Hainan area before the Beiliu-Huazhou MS5.2 Earthquake.The analysis of continuous gravity observation data is carried out from two aspects of the gravity disturbance and the tide factor change of gravity M2 wave.The analysis of mobile gravity observation data is carried out from two aspects of the differential dynamics and cumulative dynamics of gravity field.The study of continuous gravity observation data shows that the continuous gravity observation data don’t have abnormal.The results of the mobile gravity data in Leizhou-Hainan show that before the Beiliu-Huazhou MS 5.2 earthquake,there was an abnormal change in the gravity field near the epicenter.The anomaly lasted about 2 years,of which the range was about 100 km and the magnitude was about 50x10^-8m·s^-2,and the earthquake occurred on the high gradient zone of gravity field change.

关 键 词：连续重力 流动重力 重力累积变化 重力变化异常 地震 

分 类 号：P315.7[天文地球—地震学]