新疆南天山西段地区介质衰减特征研究  

STUDY OF MEDIUM ATTENUATION CHARACTERISTICS IN SOUTHERN TIANSHAN

作　　者：尼鲁帕尔.买买吐孙 阿衣仙姑.买买提 夏爱国[1] 海仁沙.司拉木 

机构地区：[1]新疆维吾尔自治区地震局,新疆乌鲁木齐830011 [2]新疆维吾尔自治区地震局喀什基准地震台,新疆喀什844000

出　　处：《内陆地震》2016年第1期41-48,共8页Inland Earthquake

基　　金：新疆地震科学基金课题(2013201)

摘　　要：利用新疆数字地震台网记录的15个台站的720条地震波形资料,用Atkinson方法联合反演得到南天山西段Q值随频率f的关系式为Q（f）=313.4f0.548;在400 km的震源距范围内,研究区地震波的几何衰减满足三段衰减模型;研究区的Q值小于天山中东段、北天山和柯坪地区的Q值,说明该区域构造活动强烈。其次根据S波衰减记录得到观测振幅谱,采用Moya遗传算法得到了新疆南天山西段15个台站的场地响应。结果显示,大多数台站的场地响应在1附近,西克尔台（XKR）、塔什库尔干台（TAG）、乌什台（WUS）和神木园台（SMY）的场地响应在1~4 Hz之间均大于2,表现出一定的放大效应,岳普湖台（YPH）呈现余弦波动,可能与台基岩性和仪器的工作状态有关。区域的选择对台站场地相应计算结果影响不大。720 waveform data recorded by 15 seismic stations were used in this research for southern Tianshan. Writers used Atkinson methods to inverse,Moya methods to inverse site response of 15 digital seismic stations,and deducted transmitting path,site response from seismic wave. Study showed that inelastic attenuation,geometric spreading patterns of southern Tianshan as well as site responses of each station were investigated. Result showed that tri-liner geometrical spreading model was available on study. Frequency-dependent Q value in this region was estimated as Q（ f） = 313. 4f0. 548,and Q value in this region was smaller than that of eastern Tianshan and Keping,which were consistent with seismic activities. Site effects of 15 seismic stations were obtained. Site response of XKR,TAG,WUS and SMY stations were greater than 2 between 1 ~ 4 Hz,and YPH appeared cosine fluctuation which may connect with LMH and equipments working status. Compared with previous research results,regional options on site corresponding calculation results had little effect. Study results provided basic data in seismology,engineering seismology using digital seismic observation data in source spectrum and simulation of strong ground motion.

关 键 词：南天山西段 非弹性衰减 几何衰减 介质品质因子 

分 类 号：P315.7[天文地球—地震学]