Relationships between gas reservoir and the evolution of stope surrounding rock fracture at the process of mining the closed distance protection layer

Overburden rock movements and fracture developments occur during mining activities. Consequently, relief gas reservoirs and migration in coal seams being mined as well as in near distant coal seams appear. We considered a gas disaster management project and rules on stope relief of gas flows together and explored a gas reservoir and the evolution of stope surrounding rock fractures in the process of mining near distant protective layers by physical simulation, numerical simulation and field testing. Different techniques provide evidence of the rules of interaction of gas reservoirs and the evolution of surrounding rock fractures and are able to find accurately the gas-rich regions around the stope. Finally, we found that these rules can provide a basis for taking measures to prevent gas accidents in the protective layer of the coalface as well as for demonstrating and designing programs to drain high concentrations of gas from the gob.