Hydrogeological supplementary exploration and safety evaluation of pressurized coal mining in low seam formation

In order to have the hydrogeological conditions of the aquifer and seam to meet the requirements of the pressurized coal mining in the low seam formation, based on the previous hydrogeological information as the basis,the ground geophysical exploration,hydrogeological drilling exploration,water pumping test,hydrclogic loggi ng,water quality analysis and other survey means were comprehensively applied to the detection study on the hydrogeological condition,watery and the hydraulic relationsh ip between the Taiyuan formation limestone and the underlying Ordovician limestone karst water. The results showed that a water inrush coefficient of No. 9 seam floor was less than 0.06 MPa 1 m,the whole block was in a safety block and No. 9 seam could be safely mined. Based on the water inrush coefficient,the danger of No. 10 ands No. 11 seam floors could be divided into two blocks. With the water inrush coefficient less than 0.06 MPa 1 m,the normal section of the seam could be safely mined. In the wate r inrush danger block,the effective water prevention and control measures could be conducted for the safety mining.