Crustal attenuation characteristics of S-waves beneath the Eastern Tohoku region,Japan

作     者：Muhammad Adeel Arshad 

作者机构：Department of Civil EngineeringUniversity of Engineering & TechnologyPeshawar 

出 版 物：《Earthquake Science》 (地震学报（英文版）)

年 卷 期：2016年第29卷第5期

页      面：259-269页

核心收录：

学科分类：0709[理学-地质学] 0819[工学-矿业工程] 07[理学] 070801[理学-固体地球物理学] 0707[理学-海洋科学] 0708[理学-地球物理学] 0818[工学-地质资源与地质工程] 0815[工学-水利工程] 0816[工学-测绘科学与技术] 0813[工学-建筑学] 0814[工学-土木工程] 0825[工学-航空宇航科学与技术] 0704[理学-天文学] 

基　　金：a part of author’s M.Sc Research under the project:‘‘Strengthening of Earthquake Engineering Center’’ funded by Higher Education Commission Government of Pakistan 

主　　题：Tohoku Generalized inversion technique Non-parametric attenuation function Seismic quality factor S-wave 

摘      要：An inversion method was applied to crustal earthquakes dataset to find S-wave attenuation characteristics beneath the Eastern Tohoku region of Japan. Accelerograms from 85 shallow crustal earthquakes up to 25 km depth and magnitude range between 3.5 and 5.5 were analyzed to estimate the seismic quality factor Qs. A homogeneous attenuation model Qs for the wave propagation path was evaluated from spectral amplitudes, at 24 different frequencies between 0.5 and 20 Hz by using generalized inversion technique. To do this, non-parametric attenuation functions were calculated to observe spectral amplitude decay with hypocentral distance. Then, these functions were parameterized to estimate Qs. It was found that in Eastern Tohoku region, the Qs frequency dependence can be approximated with the function 33 f 1.22 within a frequency range between 0.5 and 20 Hz. However, the frequency dependence of Qs in the frequency range between 0.5 and 6 Hz is best approximated by Qs （f） = 36 f 0.94 showing relatively weaker frequency dependence as compared to the relation Qs （f） = 6 f^ 2.09 for the frequency range between 6 and 15 Hz. These results could be used to estimate source and site parameters for seismic hazard assessment in the region.