利用Aki模型对宁夏及邻区尾波Q值分布特征的研究

Distribution Characteristics of QValue of Seismic Coda in Ningxia and Neighboring Areas Based on Aki Model

从2008年1月至2013年12月宁夏地震台网记录的665次ML≥2.0地震的数字地震波形资料中,选取波形记录清晰、噪声水平满足计算条件的数字地震波形记录,利用Aki模型,计算宁夏及邻区各区域尾波Q值,并与前人已有结果进行对比,得到该区尾波Q值的分布特征。结果表明:宁夏及邻区尾波Q值整体呈北高南低分布;吴忠、灵武地区该值相对较高,与该区域存在高速区相对应;阿拉善左旗西南该值较低;中卫、海原及附近地区该值相对较低,认为与该区域地壳深部的高温度与高热流值有关。

In this study,we analyze the distribution characteristics of Qvalue of seismic coda in Ningxia and neighboring areas by considering 665 digital wave data points of earthquakes with ML≥2.0from January,2008 to December,2013 recorded by the Ningxia Earthquake Network using the Aki model.The selected waveform records are clear,and the noise levels satisfy the requirements.By comparing the Qvalues of seismic coda in each area of the Ningxia Province and its adjacent region with existing results,the distribution characteristics of Qvalue of seismic coda are obtained.The results show that the Q value of seismic coda is higher in the north than in the south.The Q values of seismic coda in Wuzhong and Lingwu areas are relatively high,corresponding to the high-speed zone.The Qvalues of seismic coda in the region southwest of Alashan Zuoqi and those in Zhongwei,Haiyuan,and their adjacent regions are relatively low.These results may be associated with the high temperatures and heat-flow values in the deep crust of those areas.