Characteristics of Gas Occurrence Based on Gradual Tectonic Control Theory in Pingdingshan No.13 Mine

To clarify the control mechanism of gas occurrence laws for predicting gas disaster and gas distribution situation, we adopted gas occurrence tectonic gradual control theory to research No.13 Mine. Combined with tectonic at all levels and gas data, we analyzed the control of the regional tectonic evolution, the structures in mining area and the structures in mine on the gas occurrence. The results show that the structures of different levels control the gas occurrence within corresponding ranges. Meanwhile, the gas occurrence regularity of high in the east and low in the west in No.13 mining area is established by the regional tectonic evolution; while the gas content increasing with the buried depth is controlled by Likou syncline. Moreover, the gas distribution is different in different region and different coal seams in one mine, and the gas occurrence is controlled by the structures in the mine area. F₁ and F₃ mining area controlled by folded structures is characterized by stress concentration, high gas content and coal and gas outburst concentration. F₂ mining area controlled by normal fault has low gas content.