Observation and research of deep underground multi-physical fields—Huainan–848 m deep experiment  

作　　者：Yun WANG Yaxin YANG Heping SUN Chengliang XIE Qisheng ZHANG Xiaoming CUI Chang CHEN Yongsheng HE Qiangqiang MIAO Chaomin MU Lianghui GUO Jiwen TENG 

机构地区：[1]School of Geophysics and Information Technology,China University of Geosciences,Beijing 100083,China [2]School of Geophysics and Measurement-control Technology,East China University of Technology,Nanchang 330013,China [3]Innovation Academy for Precision Measurement Science and Technology,Chinese Academy of Sciences,Wuhan 430077,China [4]Institution of Engineering Protection,IDE,AMS,PLA,Luoyang 471023,China [5]State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines,Anhui University of Science and Technology,Huainan 232001,China [6]Institute of Geochemistry,Chinese Academy of Sciences,Guiyang 550081,China

出　　处：《Science China Earth Sciences》2023年第1期54-70,共17页中国科学（地球科学英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos.62127815,42150201,U1839208)

摘　　要：Compared with the surface,the deep environment has the advantages of allowing“super-quiet and ultra-clean”-geophysical field observation with low vibration noise and little electromagnetic interference,which are conducive to the realization of long-term and high-precision observation of multi-physical fields,thus enabling the solution of a series of geoscience problems.In the Panyidong Coal Mine,where there are extensive underground tunnels at the depth of 848 m below sea level,we carried out the first deep-underground geophysical observations,including radioactivity,gravity,magnetic,magnetotelluric,background vibration and six-component seismic observations.We concluded from these measurements that(1)the background of deep subsurface gravity noise in the long-period frequency band less than 2 Hz is nearly two orders of magnitude weaker than that in the surface observation environment;(2)the underground electric field is obviously weaker than the surface electric field,and the relatively high frequency of the underground field,greater than 1 Hz,is more than two orders of magnitude weaker than that of the surface electric field;the east-west magnetic field underground is approximately the same as that at the surface;the relatively high-frequency north-south magnetic field underground,below 10 Hz,is at least one order of magnitude lower than that at the surface,showing that the underground has a clean electromagnetic environment;(3)in addition to the highfrequency and single-frequency noises introduced by underground human activities,the deep underground space has a significantly lower background vibration noise than the surface,which is very beneficial to the detection of weak earthquake and gravity signals;and(4)the underground roadway support system built with ferromagnetic material interferes the geomagnetic field.We also found that for deep observation in the“ultra-quiet and ultra-clean”environment,the existing geophysical equipment and observation technology have problems of poor adaptability and insu

关 键 词：Multi-physical fields RADIOACTIVITY GRAVITY GEOMAGNETIC Electromagnetic EARTHQUAKE Observations deep underground 

分 类 号：P631[天文地球—地质矿产勘探]