福建地区的非弹性衰减和台站场地响应研究  

Research oninelastic attenuation and site response of seismic station of Fujian area

作　　者：段刚[1] 张丽娜[1] DUAN Gang;ZHANG Li-na(Fujian earthquake administration, Fujian Fuzhou 350003, Chin)

机构地区：[1]福建省地震局,福州350003

出　　处：《地球物理学进展》2017年第5期1886-1892,共7页Progress in Geophysics

基　　金：福建省地震局青年基金专项"福建台网接入的台湾台站场地响应研究"(Y201601)资助

摘　　要：福建台网共建有88个速度型观测台站,利用这些台站记录的50个地震波形资料,用Atkinson方法反演了福建地区的非弹性衰减,其非弹性衰减Q(f)=483.6f^(0.352),这与福建地区构造活动较为稳定,介质的均匀程度相对较高,对频率的依赖较少的理论相符.用Moya方法计算台站的场地响应,大部分台站在1~2附近波动,说明其台基良好;部分台站在高频部分出现放大效应,说明台基存在一定的风化;部分台站则在高频出现衰减,说明台基存在一定的松软沉积层.经过本文的研究,为下一步福建台网产出地震的震源参数建立数据基础,丰富了福建台网的数据服务内容.对震级校正、台站场地选点及评价、地震工程和灾害评估有一定的参考意义.Fujian seismic network has built 88 speed-type observation stations,and takes use of 50 seismic waveform data recorded by these stations, in order to invert the inelastic attenuation in Fujian region by using Atkinson method. The inversion results indicate that the inelastic attenuation is Q（ f） =483. 6 f（0.352）. There is consistent with the theory that the tectonic activity in Fujian is relatively stable,medium uniformity is relatively high and less reliance on frequency.We use the Moya method to calculate the site response of the stations. Most of them are around 1 - 2, indicating that the stylobates are good. Some of them has an amplification effect in high frequency part,showing that there is a certain degree of weathering.While some others have an attenuation in high frequency,indicating that there are some soft sediments in the stylobates. However,in order to obtain relatively reliable observation datas,we need to constantly correct the actual observation datas that the keys are the propagation path effects and site response. Propagation path effects include geometric diffusion and inelastic attenuation which is an important physical parameter of the Earth＇s media. It describes the attenuation of the seismic waves in the medium due to the noncomplete elasticity and heterogeneity of the medium. And it is usually described by Q value. It is a sensitive indicator of the change in crystal structure due to temperature and phase change. It is important value to obtain the inelastic properties and thermodynamic states of the internal media. Through the above analysis and research,this paper establishes a data base for the source parameters of earthquakes output by Fujian seismic network,and also enriches the service content of Fujian seismic network.Furthermore, it has some reference significance for correcting earthquake magnitude, selecting and evaluating station site,assessing earthquake engineering and disaster.

关 键 词：福建地区 地震台站 非弹性衰减 场地响应 

分 类 号：P315[天文地球—地震学]