Geological Characteristics And Co-production Evaluation Of Multi-coal Seams Gas Of Nanyanzhu A2 Coalbed Methane Block In Shouyang,Qinshui Basin

Aiming at the feasibility of combined mining of the main coal seams 3#,9# and15# coal of the Taiyuan Formation in Shanxi Taiyuan Formation,Nanyanzhu A2 Block,Shouyang North District,Shanxi.Based on the interpretation of basic geological parameters and reservoir pressure logging data,analysis of reservoir physical properties and lithology / water abundance of roof and floor,analysis of main control factors and mechanism of multi-layer coalbed methane co production,optimization of main parameters and prediction of feasible area of multi-layer coalbed methane co production.This paper evaluates the feasibility of combined mining of 3 #,9 #,and 15 #,and puts forward some suggestions for the next exploration and development in this area.Log interpretation results show that the main coal seam in the area is 15# coal with thick thickness;3# coal seam and 9# coal seam are locally thicker and thinner overall.The gas content of different coal seams is medium;the permeability shows a downward trend with depth,among which the permeability of the structural high point is higher,basically about 1m D;the overall reservoir pressure gradient of different coal seams is basically 0.5?0.7MPa/100m;3#,9 The roof lithology of # Coal is mainly mudstone and sandy mudstone,and the roof lithology of # Coal is mainly limestone and argillaceous limestone.Based on the comparative analysis of various parameters,it is believed that the potential of CBM in the area to obtain high production is average.Based on the consistency of coal seam thickness and permeability,the distribution of main aquifer and the drainage and water production of existing multi-layer commingled mining wells in the study area,through the numerical simulation analysis of geological influencing factors of multi-layer commingled mining,it is considered that the study area is not suitable for large-scale multi-layer commingled mining,and only local areas can try,The three sets of coal seam combined mining feasible areas in the recommended area are mainly located in the northern structural high point area,the middle part of the north is mainly 3 and 15 coal seam combined mining feasible area,and the south is mainly 15 coal seam single mining area.