An analysis of the detection effect of cross-well electromagnetic wave CT in coal mine goaf
ZHAO Xu-Chen1(), LI Xue-Jian2, CAO Fang-Zhi3, LEI Xiao-Dong1(), LI Chen1, HAN Yu-Da1
1. Beijing Institute of Geo-exploration Technology, Beijing 100120, China 2. Shenhua Baorixile Energy Co., Ltd., Hulun Buir 021025, China 3. CNBM Geological Engineering Exploration Academy Co., Ltd., Beijing 100102, China
In an open-pit coal mine in Hulun Buir of Inner Mongolia, the main mining coal seams are buried in depths ranging from 39m to 90m. Before coal mine integration, predatory mining has left many mined areas with unknown geological data, and the existence of mined-out areas has brought huge safety hazards to open-pit mining stripping. In order to find out the specific location and connectivity of the underground goaf, the authors used the cross-hole electromagnetic wave CT method to probe into the inside of the goaf in detail, and obtained a lot of real and reliable geophysical data. The analytical result shows that relatively complete rock formation electromagnetic wave absorption coefficient is in the range of 0.44~0.51Nper/m, and no water-filled goaf electromagnetic wave absorption coefficient is in the range of 0.29~0.40 Nper/m. According to the difference of electromagnetic wave absorption coefficient between goaf and surrounding rocks, the authors drew the morphological interpretation map of the goaf, and the results are basically consistent with the drilling data.
赵旭辰, 李雪健, 曹芳智, 雷晓东, 李晨, 韩宇达. 井间电磁波CT在煤矿采空区探测效果分析[J]. 物探与化探, 2021, 45(4): 1088-1094.
ZHAO Xu-Chen, LI Xue-Jian, CAO Fang-Zhi, LEI Xiao-Dong, LI Chen, HAN Yu-Da. An analysis of the detection effect of cross-well electromagnetic wave CT in coal mine goaf. Geophysical and Geochemical Exploration, 2021, 45(4): 1088-1094.
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