用叠加谱比法研究四川地区Lg尾波Q值的区域性变化  

Regional variation of Lg coda Q in Sichuan regionusing stack spectral ratio method

作　　者：毛燕[1] 徐彦[1] 胡家富[1] 丛连理[1] 王彬[2] 

机构地区：[1]云南大学地球物理系,云南昆明650091 [2]云南省地震局,云南昆明650041

出　　处：《云南大学学报（自然科学版）》2005年第2期123-128,共6页Journal of Yunnan University(Natural Sciences Edition)

基　　金：国家自然科学基金资助项目(49974012和40274030);云南省自然科学基金资助项目(99D0013M).

摘　　要：运用单台叠加谱比法,分析了成都台网4个台站的29个地震记录的垂直分量,反演得出与各射线路径相对应的Lg尾波的Q0值.结果表明:Q0值的分布特征与构造活动性密切相关.在构造活动剧烈的龙门山断裂、鲜水河断裂和安宁河断裂,尤其是在这三大断裂的交汇处,Q0值呈现出相当低的值,约在150～210的范围内.在四川盆地的大部分地区,随着构造活动的减弱,Q0值有所抬升,约为240～270.在四川盆地的东部,Q0值可达300.在离开断裂区的四川北部,Q0值在250～300的范围内变化.The vertical components of 29 earthquake records received by 4 stations of Chengdu Network were analyzed with the single station stack spectral ratio method,and inverted the Lg coda Q_0 for each path.Results indicate that the distribution characteristics of Q_0 correlates with geotectonics closely.In tectonical active regions including Longmenshan fault,Xianshuihe fault,and Anninghe fault,especially in the junction of the three faults,Q_0 exhibits very low values varying from 150-210.In most areas of Sichuan Basin,Q_0 somewhat increases,with the decreasing of tectonics whose values being from 240-270.In the east part of Sichuan Basin,Q_0 can arrive at 300.In the north part of Sichuan away from fault regions,Q_0 varies from 250 to 300.

关 键 词：叠加谱比法 LG尾波 Q 四川 

分 类 号：P315[天文地球—地震学]