Dependence of gas emission from the sources undermined by stope mine workings on the rocks displacement parameters

Abstract

The parameters are established in the work of the stope mine workings and rocks displacement, which correspond to the maxima of gas emission into the gas drainage boreholes. The angular and linear parameters of the crustal movement and rocks displacement have been calculated with the use of empirical dependences. These parameters correspond to the maxima of gas emission into the gas drainage boreholes. The obtained positive results for determining the possible areas of maximum gas emission allow us to recommend the empirical dependences for calculating the angles of maximum subsidence and complete displacements at the stage of stope works development, as well as the dimensions of the stope mine workings, at which the processes of rocks displacement reach the earth surface. The established relations between the gas drainage boreholes location and the rocks displacement zones with discontinuity make it possible to design the optimal schemes of draining-out of gases from the gas-and-coal deposits. For the first time, three independent methods have been used to determine the changes in dimensions of rocks displacement zones with discontinuity after the primary main roof squeezing until the formation of stable upper boundaries of these zones.

On the relationship between gas emission from undermined coal-bearing stratum and the intensity of coal seam mining

“…In its absence, the gas content of the mine seemingly tends to infinity. The absolute gas emission when the clean face is stopped depends on the the location of sources in the undermined coal-bearing strata, which are no longer associated with coal mining [13,14].…”