利用剖面浅析鄂尔多斯西南缘Q值与断层展布的关系  

Analysis of the Relationship Between the Profile Q Value and the Distribution of the Faults in the Southwest Edge of Ordos

作　　者：师海阔[1] 张立恒[1] 杨学锋 贺永忠[1] SHI Hai-kuo;ZHANG Li-heng;YANG Xue-feng;HE Yong-zhong(Earthquake Administration of Ningxia Hui Autonomous Region,Ningxia Yinchuan 750001,China)

机构地区：[1]宁夏回族自治区地震局,宁夏银川750001

出　　处：《防灾减灾学报》2018年第1期26-33,共8页Journal of Disaster Prevention And Reduction

基　　金：中国地震局三结合课题(CEA-JC/3JH-163003)

摘　　要：根据鄂尔多斯西南缘地区已知断层及地震分布,切出6条剖面。利用国家测震台网数据备份中心提供的2009年1月至2015年11月的地震波形数据,选取震级范围为M_L1.8~6.7,震中距小于800km的1820个地震事件的16156条Pg波到时数据,计算得到剖面Q值分布。结果表明:Q值分布与断层展布密切相关。在断层两侧,Q值会发生明显的横向梯度变化;Q值随深度变化也呈现出一定的不均匀性。推测香山—天景山断裂为一条浅部断裂,会宁—义岗断裂切割较深;岷县地区、清水—徽县一带均有一条隐伏断裂存在于中上地壳。According to the known fault and seismic distribution in the southwest edge of Ordos,six profiles were cut out.Using the cited seismic data from January 2009 to November 2015,which are supplied by Data Backup Center for China Seismic Network.1820 qualified seismic events and 16156 Pg seismic phases are selected,whose magnitude ranges from ML1.8 to ML6.7 and epicentral distances are all less than 800 kms,the distribution of profile Q value is obtained.The results show that,the distribution of Q value is closely related to the distribution of the fault zone.Obvious lateral gradient change of Q value will happen on both sides of the fault;the Q value,changing with the depth,shows a certain degree of inhomogeneity.Xiangshan-Tianjingshan fault maps a shallow one;The Huining-Yigang fault inserts deeply in the crust;There exist buried faults in the middle and upper crust of Minxian and Qingshui-Huixian region.

关 键 词：鄂尔多斯西南缘 Q值分布 断层展布 关系 

分 类 号：P315.3[天文地球—地震学]