基于多源探查的FD7逆断层含导水性判别及煤柱留设可行性分析

Identification of Water-Bearing and Conducting Properties of FD7 Reverse Fault Based on Multi-Source Exploration and Feasibility Analysis on Coal Pillar Setting

摘要: 断层防隔水煤(岩)柱留设是煤矿防治水工作的核心问题之一。传统规范按断层落差分级留设煤柱，但未充分考虑断层实际含导水性，常导致煤炭资源压滞。以朱集西煤矿东翼系统大巷掘进过FD7逆断层及11405工作面FD7断层为工程背景，提出基于地面三维地震、地面钻探、井下瞬变电磁、井下钻探及巷道实揭的多源探查信息融合方法，判别FD7逆断层含导水性，并评价断层影响下采掘水害威胁程度。结果表明：FD7逆断层为压扭性逆断层，研究区落差10~55 m，倾角40˚~60˚；断层带充填糜棱岩、泥岩及构造煤，瞬变电磁未发现低阻异常，钻探无涌水漏水，巷道实揭干燥无水，与上覆第四含水层及下伏太原组灰岩含水层无水力联系，综合判定为不含(导)水断层。水害评价显示：11405工作面导水裂缝带最大高度38.3 m，防水煤岩柱高度50.3~63.0 m，远小于煤层与“四含”间距555~661 m；底板采动破坏深度19.93~30.06 m，远小于煤层至太灰间距257 m；突水系数0.046 MPa/m，低于《煤矿防治水细则》构造破坏块段临界值0.06 MPa/m。基于上述判别与评价，论证了东翼系统大巷及11405工作面过FD7逆断层可不留设断层防隔水煤柱。研究成果为逆断层煤柱留设提供了“含导水性判别–水害评价–规范适用性分析”的系统方法，对类似条件矿井具有参考价值。

Abstract: The setting of waterproof coal (rock) pillars for faults is one of the core issues in coal mine water prevention and control. Traditional specifications set pillars according to fault throw, but often neglect the actual water-bearing and conducting properties of faults, resulting in resource sterilization. Taking the east wing main roadway crossing the FD7 reverse fault, and the FD7 fault in the 11405 working face of Zhujixi Coal Mine as the engineering background, a multi-source exploration information fusion method based on surface 3D seismic, surface drilling, underground transient electromagnetic, underground drilling, and roadway exposure is proposed to identify the water-bearing and conducting properties of the FD7 reverse fault and evaluate the water hazard threat under fault influence. The results show that the FD7 reverse fault is a compressive-torsional reverse fault, with a throw of 10~55 m in the study area and a dip angle of 40˚~60˚. The fault zone is filled with mylonite, mudstone, and tectonic coal. Transient electromagnetic exploration found no low-resistivity anomaly, drilling showed no water inrush or leakage, roadway exposure was dry, and there was no hydraulic connection with the overlying fourth aquifer or the underlying Taiyuan Formation limestone aquifer. It is comprehensively determined as a non-water-bearing and non-conducting fault. Water hazard evaluation shows that the maximum height of the water-conducting fracture zone in the 11405 working face is 38.3 m, and the waterproof coal-rock pillar height is 50.3~63.0 m, far less than the distance of 555~661 m between the coal seam and the fourth aquifer. The floor mining-induced failure depth is 19.93~30.06 m, far less than the distance of 257 m from the coal seam to the Taiyuan limestone. The water inrush coefficient is 0.046 MPa/m, lower than the critical value of 0.06 MPa/m for structural damage blocks specified in the Detailed Rules for Coal Mine Water Prevention and Control. Based on the above identification and evaluation, it is demonstrated that the east wing main roadway and the 11405 working face can cross the FD7 reverse fault without setting fault waterproof coal pillars. The research results provide a systematic method of “water-bearing and conducting property identification - water hazard evaluation - specification applicability analysis” for reverse fault coal pillar setting, which has reference value for mines with similar conditions.