Study On The Development Characteristics Of Gas Migration Channel Under High Magmatic Rock And The Law Of Gas Reservoir

Hard and thick magmatic rocks are widely distributed in China's mining areas,and the hard and thick rock formations play an important role in controlling the development and distribution of gas migration channels.The rupture of the main key layer of the hard thickness can cause the change of the gas migtation channel and the supporting stress of the working face,and induce the gas outburst resulting in a series of mine power disasters.By similar material simulation experiments,studied the development and distribution of gas migration channel under the condition of high magmatic rocks;according to the UDEC numerical simulation and theoretical analysis,studied the stress of the key layer and the working face,and the rationality of the simulation experiment is verified;an engineering example was carried out to verify that the gas outbust occurred in 10414 working face of Yangliu coal mine in Huaibei city,the following conclusions:(1)Under the condition of magmatic rocks,the development of gas migration channels is controlled by high level magmatic rocks.Before the fracture of the magmatic rocks,the height of the separation and fracture fracture is highly advanced,and it stops at the bottom of the magmatic rock,in which the transverse span of the abscission fracture gradually increases,and the fracture fracture moves forward.(2)The maximum vertical and pressure range of the key layer increases with the working surface.When the critical layer breaks,the vertical stress begins to decrease;the maximum supporting stress and pressure of the working face increases with the advancing of the working surface.When the critical layer breaks,the bearing stress of the working face increases significantly.The existence of the key layer has great influence on the supporting stress of the working face,and the rupture of the key can provide a strong dynamic impact,which poses a great threat to the coal mine safety production.(3)Room key strata formed under large area abscission layer,and cause the mine a large number of gas accumulation in the delamination of space,form the abscission layer gas,when the key layer breaking,strong shock causing abscission layer gas outburst,and cause the gas rush accident.(4)According to the formation conditions of the ionospheric gas and the mechanism of gas outburst,the ionospheric grouting and the drainage gas extraction method were used to control the gas outburst.