Research on coupling mechanism of mine structure and gas occurrence

Taking south and east Suzhou mining areas as an example, the coupling mechanism of mine structure and gas occurrence is further discussed. The results show that the regional tectonics have a distinctly control over the distribution of gas content. East Suzhou mining area, located in the overlying system of Xu-Su thrust nappe structure, has good sealing conditions to preserve gas, which leads to a well developed high-gas coal reservoir. Relatively, south Suzhou mining area lies in the underlying system, showing a low gas content. Meanwhile, mine structures also control the heterogeneity of gas distribution. For example, relatively large scale mine fractures are always the demarcation of adjacent gas division and the shear fractures is the main basis for division of relatively closed tectonic units. Moreover, shear sliding faults often change the thickness of coal seam rapidly, resulting in dangerous zones of high gas content and outburst.