含水采空区全空间瞬变电磁响应分析  

Whole-space transient electromagnetic detection of water-bearing goaf

作　　者：陈健强 李雁川[3] 田浩 李汉超 CHEN Jian-Qiang;LI Yan-Chuan;TIAN Hao;LI Han-Chao(Mine Safety Technology Research Branch of China Coal Research Institute,Beijing 100013,China;State Key Laboratory of Coal Mining and Clean Utilization,China Coal Research Institute,Beijing 100013,China;Jincheng Anthracite Mining Group Technology Research Co.,Ltd.,Jincheng 048006,China)

机构地区：[1]煤炭科学技术研究院有限公司安全分院,北京100013 [2]煤炭资源高效开采与洁净利用国家重点实验室(煤炭科学研究总院),北京100013 [3]山西晋煤集团技术研究院有限责任公司,山西晋城048006

出　　处：《物探与化探》2021年第2期546-550,共5页Geophysical and Geochemical Exploration

基　　金：煤科院科技发展基金项目技术创新基金(2019CX-II-14);国家自然科学基金青年科学基金项目(51704162)。

摘　　要：针对含水采空区全空间瞬变电磁响应信号识别问题,采用有限元数值模拟及现场实测方法,基于电动势—视电阻率及对应时深转换关系,获取了全扇面视电阻率随深度变化的空间分布规律,提取了低阻异常区测点感应电动势衰减曲线,得出了测点随探测角度变化的电动势量化变化规律。基于上述研究,开展了井下钻探验证及钻孔窥视,并对现场钻孔出水水样进行了水质分析。结果表明:含水采空区的瞬变电磁响应横向角度对应一致性高于纵向深度;其感应电动势升幅与感应电动势差值变化趋势相反,呈现出在二次场观测初期急剧增大而后趋缓的特征,最大升幅可达10倍以上。钻探工程及化探分析进一步验证了物探成果。Aiming at tackling the problem of whole-space transient electromagnetic response signal identification in water-bearing goaf and based on induced electromotive force(EMF)-apparent resistivity and time-depth conversion relationship,the authors obtained the spatial distribution law of apparent resistivity with depth variation of the whole sector by using the finite element numerical simulation and field measurement method,extracted the EMF attenuation curve of the measuring point in the low resistance abnormal area,and calculated the voltage rise amplitude of the measuring point varying with the detection angle.Based on the above research,the authors carried out the drilling verification and borehole peeping,and analyzed the content of the drilling water samples.The results show that the transverse angle consistency of transient electromagnetic response of water-bearing goaf is higher than that of vertical depth,and the rising amplitude of EMF in the abnormal region of low resistance is opposite to the difference of induced voltage,which shows a sharp increase in the initial stage of secondary field observation followed by slowing down,reaching more than 10 times on the whole.Drilling engineering and geochemical exploration analysis further verify the geophysical exploration results.

关 键 词：含水采空区 全空间瞬变电磁法 有限元模拟 电动势升幅 钻探 化探 

分 类 号：TD166[矿业工程—矿山地质测量]