芦山7.0级、汶川8.0级地震与巴颜喀拉地块东缘区域历史地震  

The M 7.0 Lushan,the M 8.0 Wenchuan earthquakes and the history earthquakes in the eastern border area of the Bayan Har block

作　　者：杜方[1] 苏有锦[2] 龙锋[1] 赵小艳[2] 吴江[1] 

机构地区：[1]四川省地震局,成都610041 [2]云南省地震局,昆明650224

出　　处：《地球物理学进展》2015年第4期1569-1579,共11页Progress in Geophysics

基　　金："十二五"国家科技支撑计划项目课题(2012BAK19B01)-07;01专题;中国地震局M 7工作专项资助

摘　　要：2013年4月20日在龙门山断裂南段发生的芦山M7.0级地震已过去近1年.本文根据四川省地震台网资料和收集的国内外相关历史资料,研讨了巴颜喀拉地块东缘区域龙门山断裂、岷江断裂、虎牙断裂等历史地震活动;分析了龙门山断裂带2008年5月12日汶川8.0级和2013年4月20日芦山7.0级地震余震时空、震源机制及破裂扩展等特征;讨论了巴颜喀拉地块东缘区域的能量释放特征等.结果表明:(1)芦山7.0级地震西南的龙门山断裂南段仍存在尚未破裂的背景性破裂空段;(2)芦山7.0级地震与汶川8.0级地震两余震区之间的空段区存在能量待释放;(3)龙门山断裂中北段(在汶川余震区内)的北川附近存在能量释放不充分的局部区域.It is almost one year since on 20 April 2013 the M7.0Lushan Earthquake occurred on the southern segment of the Longmenshan fault in the Sichuan.According to the data of the telemeter seismographic network in Sichuan and the correlative historical earthquake information from internal and overseas, we research the historical seismicity along the Longmenshan,the Minjiang and the Huya faults in the eastern border area of the Bayan Har block. We analyze the characteristics of the aftershock distribution, the focal mechanism and the extended rupture along the Longmenshan fault zone of on the 12 May,2008 an M 8.0 Wenchuan earthquake and on the 20 April,2013 an M 7.0 Lushan earthquake.We discuss the features of energy release in the eastern border area of the Bayan Har block.Our results show that：（1）There is still a background blank part of the south segment of the Longmenshan fault on the southwest of the M7.0Lushan earthquake.（2）There is a short segment of energy possibly to be released soon between two aftershock areas of the M 7.0 Lushan earthquake and the M 8.0 Wenchuan earthquake.（3）The energy released in a local area near the Beichuan is not sufficient（in the aftershock area of the M 8.0Wenchuan earthquake）.

关 键 词：芦山7.0级地震 汶川8.0级地震 巴颜喀拉地块 龙门山断裂带 震源力学机制 

分 类 号：P315[天文地球—地震学]