Dynamic Variations of the Gravity Field before and after the M5. 1 Wen’an Earthquake in Hebei Province  

作　　者：Wang Wuxing Shi Yaolin Zhang Jing Shi Yanhua 

机构地区：[1]Institute of Earthquake Science, China Earthquake Administration, Beijing 100036, China [2]Laboratory of Computational Geodynamics, Graduate University of the Chinese Academy of Sciences, Beijing 100049, China [3]B aoding Observation Team of Earthquake Administration of Hebei Province, Baoding 071000, China

出　　处：《Earthquake Research in China》2010年第1期22-30,共9页中国地震研究（英文版）

基　　金：Supported by the Technology Research and Development Program of Institute of Earthquake Science, CEA;the National Key Technology R&D Program(2006BAC01B02-02),China

摘　　要：In order to explore the abnormal variations before and after the Wen＇an MS. 1 earthquake on July 4, 2006, the gravity data observed by the Wenba Gravity Observation Network before and after the earthquake was analyzed. The relationships between gravity change and vertical displacement and shallow groundwater level were discussed, and elevation correction of the gravity was preliminarily performed. The results show that there were abnormal gravity changes before the MS. ! earthquake, which appeared as gravity rising in the whole observation network, especially in the south part. A high gradient of gravity variation appeared around the epicenter before the MS. 1 earthquake, especially during the short period between October 2005 to April 2006. The boundary of the positive and negative gravity variations gradually deflected and began to recover from October 2007.In order to explore the abnormal variations before and after the Wen'an M5. 1 earthquake on July 4,2006,the gravity data observed by the Wenba Gravity Observation Network before and after the earthquake was analyzed. The relationships between gravity change and vertical displacement and shallow groundwater level were discussed,and elevation correction of the gravity was preliminarily performed. The results show that there were abnormal gravity changes before the M5. 1 earthquake,which appeared as gravity rising in the whole observation network,especially in the south part. A high gradient of gravity variation appeared around the epicenter before the M5. 1 earthquake,especially during the short period between October 2005 to April 2006. The boundary of the positive and negative gravity variations gradually deflected and began to recover from October 2007.

关 键 词：Wen＇an earthquake Wenba Gravity Observation Network Dynamic gravity change 

分 类 号：P315.7[天文地球—地震学] P312.1[天文地球—固体地球物理学]