基于Sato模型研究内蒙古赤峰及周边地区尾波Q值特征  

Q value Characteristics in Chifeng and Its Surrounding Area based on Sato Model

作　　者：李娟[1] 韩晓明[1] 裴东洋 王禄军 LI Juan;HAN Xiaoming;PEI Dongyang;WANG Lujun(Earthquake Agency of Inner Mongolia Autonomous Region,Hohhot 010010,China)

机构地区：[1]内蒙古自治区地震局,呼和浩特010010

出　　处：《华北地震科学》2022年第1期77-83,共7页North China Earthquake Sciences

基　　金：中国地震局“三结合”课题(3JH-202002006);中国地震局地震科技星火计划(XH20015Y);震情跟踪定向工作任务(2020010101);内蒙古自治区地震局局长基金课题(2019JP02)。

摘　　要：以赤峰及周边地区作为研究区域,选取2013年以来17个台站记录到的128次M_(L)≥2.5地震的波形记录,基于Sato模型计算分析了尾波Q_(C)值的时空变化特征。结果表明,赤峰及周边地区Q_(C)值与频率的关系为Q_(C)(f)=58.34±25.88f^(0.9118±0.0849),衰减参数Q0与对频率的依赖参数η值成反比;Q_(0)总体呈现西高东低的分布特征,且与断裂构造、地震活动性和基岩岩性密切相关;震例回溯检验结果显示,通辽5.3级地震前后,震源区的尾波Q值表现出了典型的“震前减小、临震升高、震后恢复”的变化过程,表明通过尾波Q值的时空变化可捕捉到震源区地壳介质体的非均匀性、衰减特征、介质应力状态和孕震信息。Taking Chifeng and its surrounding areas as the research area,the waveform records of 128 earthquakes with M_(L)≥2.5 recorded by 17 stations since 2013 are selected,and the temporal and spatial variation characteristics of coda Q_(C) value are calculated and analyzed based on Sato model.The results show that the relationship between Q_(C) value and frequency is Q_(C)(f)=(58.34±25.88)f^((0.9118±0.0849)).The attenuation parameter Q_(0) is inversely proportional to the frequency dependent parameterη;Q0 is high in the west and low in the east,and is closely related to fault structure,seismicity and bedrock lithology;The results of retrospective test show that before and after the Tongliao M_(S)5.3 earthquake,the Coda Q value in the focal area manifests a typical change process of"decrease before earthquake,rise before earthquake and recovery after earthquake".It shows that the heterogeneity,attenuation characteristics,medium stress state and seismogenic information of the crustal medium body in the focal area can be analyzed by the temporal and spatial variation of Coda Q value.

关 键 词：尾波Q值 SATO模型 赤峰及周边地区 

分 类 号：P315.31[天文地球—地震学]