Geodynamics and gas release from mined-out space in the Vorkuta coal mines

Abstract

The results of the analysis of the character of the growth with depth of methane content in beds and host rocks of coal deposits in the Pechora basin and the factors affecting it are presented. On the basis of field measurements of methane emission dynamics in the mine workings of a number of mines of the Vorkuta coal field and their statistical processing the effect of the increase in the relative methane emission by increasing the size of the mined-out space - the number of the waste pillars and the distance of the working face from the cut mine working is shown. The efficiency of the degassing schemes used to reduce gas release from the surrounding rock masses under development is analyzed. Geomechanical and gasdynamic models of a complexly structured undermined rock mass are proposed, allowing to justifiably calculate parameters of permeability distribution over its volume, air leakage fluxes from the cleaning face and gas-air mixture in the mined-out spaces.