Hydrogeological characteristics and their control on coalbed methane in Binchang mining area

Hydrogeological conditions are critical factors of coalbed methane accumulation, which play an important role in the migration and conservation of coalbed methane. This paper took a detailed discussion on the hydrogeological characteristics in Binchang mining area. Combined with the characteristics of measured gas content, the methane enrichment controlled by hydrogeological conditions in the area was studied. The results show that the structure of the study area is simple and there's no significant hydrodynamic contact between the aquifer in coal measure of Yan'an Formation and other aquifers, which is favorable to the accumulation of coalbed methane, and the groundwater replenishment of the coal strata can only come from the lateral provision of areas outside the study area. According to the hydrodynamic intensity the study area is divided into three parts:lateral runoff recharge area, runoff area and the relative stagnation area. The relative stagnation area located in the southeastern area is also the low-lying area of potential hydro-energy, which is favorable to the accumulation of coalbed methane. Meanwhile, the gas content of the southeastern coal bed is the highest, which indicates that hydrogeological conditions do play a key role in coalbed methane reservoirs.