Background  Borehole geophysical prospecting technology for coal mines integrates the advantages of both drilling and geophysical prospecting. Accordingly, multiple critical advances have been achieved in its applications to the technologies and equipment for intelligent coal mining in recent years, enabling long-distance, relatively high-precision geological exploration. This technology plays an increasingly important role in a range of fields, including deep mineral resource exploration and the reconnaissance surveys of hidden disaster-causing factors, providing robust support for safe and efficient coal mining.

Advances  This study systematically reviews the development history of borehole geophysical prospecting technology, elaborating advances in research on the methodology, theories, and inversion imaging of various techniques, including borehole transient electromagnetics (TEM), borehole radar, borehole direct current resistivity, cross-hole electrical resistivity tomography, borehole seismology, borehole natural gamma-ray logging, and multi-source borehole data fusion. These techniques offer distinct advantages in terms of the identification of low-resistivity anomalies, the detection of high-resolution interfaces, lithological classification, and the detection of hydraulically conductive structures. In combination with the demand for practical applications in coal mines, these techniques have achieved significant results in the detection of goaves, faults, collapse columns, and water yield anomalies, as well as the evaluation of grouting effects.

Prospects  This study proposes future prospects for the development of borehole geophysical prospecting technology, presenting three major development directions. First, it is recommended to establish a technical system of multi-field coupling coupled with coordinated exploration. To this end, it is necessary to develop self-adaptive denoising algorithms for strong interference environments and construct accurate full-space field propagation models. These efforts will improve the detection accuracy from a meter to a decimeter scale while also promoting the collaborative observation and coupling analysis of multiple fields, such as electromagnetic and wave fields. Second, it is advisable to conduct R&D of intelligent equipment for borehole geophysical prospecting technology. To achieve this, full-data acquisition should be adopted to enhance weak signals, and omnidirectional 3D detection should be developed. Furthermore, it is necessary to address key technical bottlenecks, such as drill rode materials, noise suppression, and data transmission, and to advance the R&D of equipment for measurement while drilling. Third, fine-scale inversion imaging and multi-method integration should be strengthened. Specifically, it is necessary to achieve rapid, joint inversion based on big data; build multi-parameter, dynamic monitoring and early-warning platforms; deepen the application of artificial intelligence algorithms in data processing, and enhance the adaptability and accuracy of borehole geophysical prospecting technology under complex geological conditions. The results of this study will provide more robust support for efficient coal exploration, along with the prevention and control of mine disasters.