摘要
简要介绍地电阻率交流观测的原理及方法,并在江宁台开展井下地电阻率交流观测实验。初步观测结果表明,井下地电阻率交流观测的抗地铁干扰效能优于井下直流观测,且5 Hz的观测要优于1 Hz;井下地电阻率1 Hz、5 Hz交流观测与直流观测反映的相对变化一致性较好,其数值差异不影响地震观测;连续降雨使得交流地电阻率出现下降变化,交流5 Hz比1 Hz更明显,最大下降幅度约0.92%,且连续降雨可能会对地铁干扰起到一定的放大作用;地电阻率交流观测使用趋肤深度来探讨探测深度,由于趋肤深度仅与频率有关,尚需做进一步研究。
This article introduces the principles and methods of AC resistivity observation and conducts an experiment on AC resistivity observation in underground environment at Jiangning Station.The preliminary results show that the anti-interference effect of AC resistivity observation in underground environment is better than that of DC observation,and 5Hz observation is better than 1Hz observation.The relative consistency between the AC resistivity observation and DC observation of underground resistivity at 1Hz and 5Hz is good,and the numerical difference does not affect seismic observation.Continuous rainfall causes a decrease in AC resistivity,and the decrease at 5Hz is more significant than that at 1Hz,with a maximum decrease of about 0.92%.Continuous rainfall may also amplify subway interference.The depth of exploration using AC resistivity observation is discussed using the skin depth,which is only related to the frequency and needs further study.
作者
樊晓春
高可伟
单友磊
FAN Xiao-chun;GAO Ke-wei;SHAN You-lei(Nanjing Earthquake Monitoring and Warning Center,Nanjing,Jiangsu 210008;Nanjing Emergency Management Bureau,Nanjing,Jiangsu 210008;Suqian Seismological Bureau,Suqian,Jiangsu 223800)
出处
《山西地震》
2023年第1期24-29,36,共7页
Earthquake Research in Shanxi
基金
中国地震局地震科技星火计划(XH19015YSX)。
关键词
地电阻率
交流
直流
井下观测
地铁干扰
Ground resistivity
AC
DC
Underground observation
Subway interference
