Detection of Coal Seam Floor Failure Depth Through Borehole Direct Current Resistivity Monitoring

Accurately monitoring the mining-induced floor failure depth during coal seam extraction remains a critical technical challenge for preventing water inrush disasters. To address the limitations of existing methods, including low efficiency in borehole observation and insufficient resolution in geophysical detection, this study proposes a novel floor failure depth monitoring technique based on borehole direct current electrical method. By deploying electrodes within boreholes, this approach directly acquires high-resolution resistivity profiles along vertical sections. Numerical simulations were first conducted to reveal the dynamic evolution patterns of apparent resistivity in mining-disturbed floor failure zones. Subsequently, field implementation at a typical coal mine demonstrated the methodology's effectiveness through monitoring electrical property variations in floor strata during pre-mining, active mining, and post-mining stages. This research breakthrough overcomes the technical limitations of conventional methods in real-time monitoring and detection accuracy, providing a reliable risk assessment tool for water inrush prevention in deep coal mining operations..