Control of geological factors on gas occurrence in Songhe Coal Mine

Mastering the characteristics of coal seam gas occurrence can provide theoretical guidance for coal seam gas resource development and gas disaster control. In order to reveal the controlling geological factors on the gas occurrence in Songhe Coal Mine, the characteristics of structure of mine area, mine structure and small structure are analyzed by geological statistics method and structure control theory, combined with the characteristics of tectonic location, tectonic evolution and regional tectonic stress field, and their controlling effect on gas occurrence is discussed. The results show that the coal seam of Panjiang Mining Area is mainly affected by Yanshan Tectonic and Himalayan Movement, the sedimentary environment of alternating marine facies, tectonic uplift and weathering denudation in the later period lead to weathering denudation of anticlinal coal seam and preservation of gas in synclinal coal seam, and the gas in coal seam increases gradually from the synclinal flank to the core. The “triangle arc system” tectonic stress field controls the tectonic deformation and tectonic coal development in the mining area. The top corner of the “triangle arc system” structure has strong tectonic deformation and serious coal deformation, and the gas content is relatively high, while the side of the “triangle arc system” structure has weak tectonic deformation and less tectonic coal, and the gas content is relatively low. Songhe Coal Mine is located in weak tectonic deformation area of the Tucheng-N-wing on the edge of the “triangle arc system” structure, resulting in little tectonic damage to the coal seam, low degree of tectonic coal development as a whole, only compression or compression-torsion fracture developed in local coal seam. It is determined that the buried depth of coal seam is the main control factor of gas occurrence in Songhe Coal Mine. The area near compressive or compressive torsion fracture is the focus of local gas disaster control. It is of guiding significance for Songhe Coal Mine and other coal mines with similar geological conditions to implement accurate gas control.