基于徐州地震台四分量钻孔应变的区域应变场特征  

Studying the characteristics of regional strain field using four-component borehole strain observations from Xuzhou Seismic Seismic

作　　者：郝冉 立凯 何斌 董传磊 杨驰 刘冬冬 高明智 张岑 许炳 HAO Ran;LI Kai;HE Bin;DONG Chuanlei;YANG Chi;LIU Dongdong;GAO Mingzhi;ZHANG Cen;XU Bing(Xuzhou Seismic Station,Jiangsu Province 221008,China)

机构地区：[1]江苏省徐州地震台,江苏221008

出　　处：《地震地磁观测与研究》2024年第5期122-130,共9页Seismological and Geomagnetic Observation and Research

基　　金：连云港市科技局重点研发计划(社会发展)(项目编号:SF2326);江苏省地震局青年科研基金(项目编号:202412);江苏省地震局青年科研基金(项目编号:202413);中国地震局监测、预报、科研三结合项目(项目编号:3JH-202401039)。

摘　　要：利用徐州地震台四分量钻孔应变仪2009—2022年观测资料,基于力学转换和多尺度变化数据拟合,分析观测区域应力应变状态。结果表明,观测期间,该台测点附近区域呈稳定的受压状态,主应变变化速率稳定,最大和最小主应变年变化分别约为-4 132×10^(-10)和-6 788×10^(-10),面应变和剪应变年变化分别约为10 919×10^(-10)和1 328×10^(-10),应变变化主方向指向NE136°。结合潮汐调和分析法绘制潮汐因子响应图,发现四分量钻孔应变仪潮汐因子增大的长轴方向与最大主压应变方向基本一致,为准确判断区域应力状态提供了重要依据。选取GNSS数据分析江苏及邻区水平运动速度场,结果显示,江苏地区整体运动趋向SE,与四分量钻孔应变仪观测的应变变化主方向一致,进一步验证了徐州地震台钻孔应变观测数据的可靠性。Using the four-component borehole strainmeter data collected by the Xuzhou Seismic Station from 2009 to 2022,this study analyzed the stress-strain state of the observation area through mechanical conversion and multiscale data fitting.The research results show that the observation area near the Xuzhou Station exhibited a stable over-pressured state during the observation period,with stable rates of change in principal strain.The annual change rates of maximum and minimum principal strain were approximately-4132×10^(-10) and-6788×10^(-10),respectively,while the annual change rates of plane strain and shear strain were approximately 10919×10^(-10) and 1328×10^(-10).The principal strain change direction was 136°.By combining the tide harmonic analysis diagram drawn using the Venetikov tidal harmonic analysis method,it was found that the direction of the tidal factor increase in the four-component borehole strainmeter was consistent with the direction of the maximum principal compressive strain calculated through fitting,providing important evidence for accurately judging the regional stress state.To analyze the stress field characteristics from a broader perspective,this study also used GNSS data to analyze the horizontal velocity field in Jiangsu and its neighboring regions.The GNSS analysis results show that Jiangsu as a whole exhibits a southeastward movement trend,which is consistent with the principal strain change direction observed by the four-component borehole strainmeter,further verifying the reliability of the observation data collected by the Xuzhou Station.

关 键 词：应力应变特征 调和分析法 主应变方向 四分量钻孔应变仪 

分 类 号：P315.78[天文地球—地震学]