Analysis of inducing factors for gas outburst accident in Tian’an No.13 Mine, Henan Province

Coal and gas outburst is one of the most severe dynamic disasters restricting safe and efficient mining in deep coal mines. Taking Tian’an No.13 Mine in Pingdingshan, Henan Province as the research object, this study adopts theoretical analysis, field measurement and geological spatial modeling to systematically reveal the geological inducing factors and control mechanisms of gas outbursts. The results show that geological structures are the primary qualitative control factor for gas enrichment and outburst occurrence. Compressional faults, syncline axes and anticline limbs form stress-concentrated gas accumulation zones, while tensional normal faults provide channels for gas escape;. Gas content exhibits clear zoning thresholds specific to this mine: areas with gas content > 9 m³/t are high-gas zones where all outburst points are located, and outburst risk rises sharply when gas content exceeds the mine-specific critical value of 15 m³/t. The mine is divided into three outburst risk zones by coupling geological structure, coal thickness and gas content indicators, including strong-coupling high-risk areas (coal thickness > 5 m, gas content > 12 m³/t), medium-coupling medium-risk areas (coal thickness 3 ~ 5 m, gas content 6 ~ 12 m³/t) and weak-coupling low-risk areas (gas content < 6 m³/t). This study clarifies the geological genesis of regional gas outbursts and provides targeted theoretical and technical references for gas disaster prevention in deep folded outburst coal mines with similar geological conditions.