Application of Gas-geology Law Method in Prediction of Coal Seam Gas Content

The prevention and control technology of gas disaster in coal mine is based on the distribution characteristics of the coal seam gas content. In this paper, it analyzed the control effect of the fault for the coal and gas distribution in the study area, and discussed the law of gas accumulation in the two fault walls from the mechanical analysis point by the fault mode of Anderson, which revealed the law of gas geology in the study area. It was thought that Aishan fault presented as sealing property under the subduction of Guodishan fault, and the coal in the two walls of which sheared and damaged seriously. Coal seam permeability decreased sharply in the failure zone, so it was difficult for the gas to dissipate. The coal seam gas content nearby the two walls of fault was relatively high, which enriched the gas. It presented that the coal seam gas content declined and tended to be stable condition from the near to the far at a distance from the fault. It selected the east wing of Ji′er mining block of JI_16-17 Coal Seam in No.11 Mine of Pingdingshan Coal Mine as the application area, established the quantitative relation of the burying depth and the distance from the fault with the gas content, and predicted the distribution of coal seam gas content in the unmining areas. Then it contrasted predictive values with measured values in the production, the relative error was under 5%, which verified the reliability of this method.