摘要
选取甘—青地区地球物理台网钻孔应变2021年1月至2022年1月数据计算其面应变相关系数、主应变、主方位角并进行投影,以面应变相关系数和数据精度进行质量控制,以主应变、主方位角及其地图投影分析甘—青区域钻孔应变的空间分布特征和时间变化特征。分析发现2021年主应变、主方位角及其地图投影变化能清晰地映证该区域构造运动,2022年1月8日门源6.9级地震时钻孔应变主方位角、最大主应变投影同震变化与此次地震地表同震位移场、应变场变化一致。上述发现为研究区域地质构造变化,对该地区地震危险性跟踪及短临跟踪提供参考。
In this paper,the correlation coefficient of surface strain,the principal strain,and the principal azimuth were calculated and projected by using the borehole strain data from Gansu-Qinghai geophysical network from January 2021 to January 2022.The correlation coefficient of surface strain and the data precision were used for data quality control.On this basis,the spatial distribution and temporal variation characteristics of borehole strain in Gansu-Qinghai area were analyzed.The results showed that the changes of principal strain,principal azimuth,and map projection in 2021 can clearly reflect the tectonic movement in the study area.The coseismic changes of the principal azimuth and maximum principal strain projection are consistent with the changes of surface coseismic displacement field and strain field caused by the Menyuan M_(S)6.9 earthquake on January 8,2022.The above results can benefit the investigation of geological structure changes,and provide support for the seismic risk tracking and imminent earthquake prediction in the study area.
作者
闫勋
高曙德
姜振海
李娜
武善艺
柴源
曹喜
YAN Xun;GAO Shude;JIANG Zhenhai;LI Na;WU Shanyi;CHAI Yuan;CAO Xi(Lanzhou Institute of Seismology, CEA, Lanzhou 730000, Gansu, China;Lanzhou Geophysics National Observation and Research Station, Lanzhou 730000, Gansu, China)
出处
《地震工程学报》
CSCD
北大核心
2022年第2期488-500,共13页
China Earthquake Engineering Journal
基金
甘肃省地震局地震科技计划青年基金(2020Q03)
国家自然科学基金重点项目(U2039206)
中国地震局兰州地震研究所创新团队专项(2019TD0203)。
关键词
钻孔应变
主方位角
主应变
同震响应
构造变化
borehole strain
principal azimuth
principal strain
coseismic response
tectonic change
