紫坪铺水库地区尾波Q_C值研究

利用Sato模型研究了汶川 M_S8.0地震前位于震源区的紫坪铺水库地区尾波 Q_C值特征. 结果表明,库区 Q_C值与频率有很强的依赖关系,4个台站的平均 Q_C=21.6 f~(1.211),尾波 Q_0值较小,平均为21.6. 离震群最近的MZP台 Q_0最大,为29.0,离震群最远的BAJ台 Q_0最小,为13.9. 这种尾波 Q_0值的差别可能与尾波 Q 值所反映的介质深度存在一定的关系,而较小的流逝时间可能是这里η值偏高的原因之一.

Coda Wave Q_C Values in the Zipingpu Reservoir Area,Sichuan Province

Using Sato model, this article studied the characteristics of coda wave Q values varied with time near the Zipingpu reservoir located at the hypocenter region of the 2008 Wenchuan M_S8.0 earthquake. The results show that Q_0 of coda waves recorded by the 4 stations near the Zipingpu reservoir is relatively small and η is relatively big. Q_0 of the MZP station which is the nearest station to the earthquake swarm is the biggest, and has a value of 29.0. On the other hand, Q_0 of the BAJ station which is the farthest station to the earthquake swarm is the smallest, and has a value of only 13.9. The difference of Q_0 can be attributed to the medium′s depth reflected by the coda wave Q values and small elapse time could be one of the reason for the relatively big η value.