摘要
根据对常德1631年地震事件的史料鉴别,尤其是江陵为典型七度震害这一事实,运用震声传播方向和地光物理场以及地震烈度衰减关系,拟合推断此地震事件的序列主要由安乡北6 3/4级地震、常德北太阳山7级地震、澧县6级地震、大庸6级地震和澧县—安乡6 1/2级地震组成,相应的地震地质背景是江汉—洞庭地区晚更新世以来的剩余形变呈四象限分布。若考虑地震-构造相关分布为“Z”字型,则该地震事件的主控构造——太阳山断裂带东断裂具左旋走滑的力学机制。根据区域地震—构造相关发展过程,常德大震事件可视为1668年郯城8 1/2级地震的前震序列组成部分。
On the basis of distinguishing the history data of the Changde seismic event in 1631 year, particularly paying attention to fact of typical intensity Ⅶ in the Jiangling city, and making use of seismic sound propagation and seismic light field as well as statistical relation of intensity attenuation, it is inferred fittingly that sequences of the Changde great seismic event consist principally of the North Anxiang earthquake (M= 6 3/4), the North Changde earthquake (M= 7), the Lizhou earthquake (M=6), the Dayong earthquake (M=6) and the Lizhou--Anxiang earthquake (M= 6 1/2). The seismogeological background related with this event is a four quadrant distribution of residual deformation field in the Jianghan-Dongting region since Epipleistocene. If corresponding distribution between seismicity and structure is considered as 'Z' type, then east fault of the Taiyangshan fault zone that controlling mainly the event has be characterized by a left-lateral slip mechanism. In addtion, the Changde great seismic event has been probably one of preseismic sequences of the Tancheng great earthquake (M=8 1/2), in term of development process of seismicity associated with tectonic zone.
出处
《地壳形变与地震》
CSCD
1993年第4期17-23,共7页
Crustal Deformation and Earthquake
关键词
多场点群发
断裂带
地震活动性
Changde great seismic event
multi-site swarm
four quadrant residual deformaiton
Taiyangshan fault zone
