煤矿隐伏地质异常体地孔瞬变电磁法三分量探测技术  

Three-component detection technology of down-hole TEM for hidden geological anomalies in coal mines

作　　者：高小伟 GAO Xiaowei(CCTEG Xi’an Research Institute(Group)Co.,Ltd.,Xi’an 710077,China)

机构地区：[1]中煤科工西安研究院(集团)有限公司,陕西西安710077

出　　处：《煤炭科学技术》2025年第1期237-245,共9页Coal Science and Technology

基　　金：国家重点研发计划资助项目(2022YFC3005601);国家自然科学基金面上资助项目(42374176)。

摘　　要：为了满足煤矿隐伏地质异常体精细探查的需求,实现钻孔周围隐伏水害的精细刻画与解释,提出了煤矿地孔瞬变电磁法三分量孔旁地质异常体定位技术,该方法通过地面大功率发射异常场信号、地面垂直钻孔中接收关断后的二次场三分量信号来探测钻孔周围地质异常体。首先采用Max-well软件分别计算了钻孔不同方位异常体的三分量响应,发现地孔瞬变电磁法接收探头离异常体近,三分量异常响应明显,且组合形态不同,可依此定性判断异常体所在钻孔的方位;进一步对煤矿上常见的含导水陷落柱、含水断层和积水采空区模型的异常三分量响应进行数值模拟,发现不同异常体由于规模、异常体姿态不同,其产生的三分量异常响应曲线幅值形态不同,依此可以定性推断异常体类型;然后采用了电流环反演技术对理论含导水陷落柱、含水断层和积水采空区模型进行了异常体空间定位。结果表明:利用地孔瞬变电磁三分量异常响应能实现钻孔周围含导水异常体的空间定位,并能获得异常体的空间位置、规模和姿态等参数。最后在内蒙古某矿针对三维地震圈定的疑似陷落柱开展了地孔瞬变电磁探测,试验采用2个方位的发射源进行了激发,并对采集的数据进行了异常三分量反演,成功实现了疑似陷落柱的空间定位,并获得了疑似陷落柱的规模和姿态,探测结果在后期巷道掘进过程中得到了超前探测钻孔的验证。理论模型与试验数据表明地孔瞬变电磁法三分量异常定位技术可作为煤矿地面垂直钻孔中探查钻孔周围地质异常体的有效手段。To meet the geological requirements for detailed exploration of concealed anomalies in coal mines and to accurately delineate and interpret hidden water hazards around boreholes,a three-component geological anomaly localization technique using borehole transi-ent electromagnetic methods is proposed.This technique detects geological anomalies around boreholes by transmitting high-power abnor-mal field signals from the surface and receiving secondary three-component field signals from the vertical borehole after shut-off.First,the Maxwell software is used to calculate the three-component responses of anomalies at various orientations around the borehole,showing that the transient electromagnetic method produces stronger three-component anomaly responses when the probe is closer to the anomaly,with different combined response patterns.This enables the qualitative determination of the anomaly’s orientation relative to the borehole.Additionally,numerical simulations of three-component responses are conducted for common anomalies in coal mines,such as water-bear-ing collapsed columns,water-bearing faults,and flooded goaf areas.The simulations reveal that the amplitude and shape of the three-com-ponent anomaly response curves differ due to the varying sizes and orientations of the anomaly bodies,allowing for the qualitative identi-fication of the anomaly type.Next,the current loop inversion technique is applied to spatially localize the anomaly bodies in theoretical models of water-bearing collapsed columns,water-bearing faults,and flooded goaf areas.The results demonstrate that the three-compon-ent anomaly responses from borehole transient electromagnetic surveys can effectively localize water-bearing anomaly bodies around the borehole and provide information on their location,size,and orientation.Finally,borehole transient electromagnetic detection is conduc-ted on a suspected collapsed column identified by three-dimensional seismic data at a mine in Inner Mongolia.Two transmitting sources at different orientations

关 键 词：地孔瞬变电磁法 陷落柱 断层 采空区 三分量 异常定位 

分 类 号：P631[天文地球—地质矿产勘探]