Abstract:
The efficient and intelligent production in coal mining necessitates more precise detection of hidden underground disaster-causing factors. Rapid excavation faces challenges in the accuracy and efficiency of detecting coal-rock interfaces, geological structures, and water-bearing anomalies ahead of the working face. To address issues such as limited construction space, strong electromagnetic interference, and long distance detection anomalies, this study proposes an integrated advanced borehole detection system combining drilling and geophysical methods for areas ahead of tunneling. To enhance radial long distance detection range and anomaly imaging precision, a virtual wavefield full-waveform inversion algorithm for pseudo-acoustic media based on wavefield inverse transformation and a three-component spatial positioning algorithm were developed. These enable borehole Transient Electromagnetic (TEM) methods to achieve intelligent inversion and 3D imaging of concealed water-bearing anomalies near the borehole. Innovative techniques were also introduced for borehole radar, including an in-situ method for determining coal-seam radar wave velocity and a spatially constrained migration imaging method guided by borehole trajectory, significantly improving the identification accuracy of coal-rock interfaces and geological structures. To overcome the limitations of single-method detection, a multi-parameter, multi-component integrated borehole detector was developed, combining borehole TEM, radar, and natural gamma methods. The compatibility of simultaneous multi-frequency electromagnetic wave detection was verified. A multi-source data fusion and interpretation platform with multi-borehole comparison and multi-parameter linkage analysis functions was established. This platform enhances geological interpretation accuracy and lithological resolution through collaborative data inversion, reducing interpretation ambiguity and forming a complete intelligent borehole advance detection and identification system. Field applications demonstrate that this technology is suitable for rapid excavation in coal mining. It enables precise detection within a radial range of 30 meters over advance distances exceeding
1000 meters in a single drilling run. This effectively resolves the conflict between exploration and excavation sequences, significantly improves roadway driving efficiency and safety, and provides robust geological support for the green and high-efficiency development of coal mines.