Preliminary Study on Water Richness Evaluation Methods of Coalbed Methane Reservoirs and Their Main Water-filled Aquifers
Based on the existing regional hydrogeology,surface geological mapping,drillhole construction and recording data,the waterrichness evaluation was carried out in three sets of different formations of Changxing Formation,Longtan Formation and Maokou Formation.In each set of Formation,a total of six evaluation indexes were selected,including the rate of drillhole water level rise and fall,core recovery rate,drilling fluid consumption,drillhole water gushing,core fracture development degree and core karst development.Each index is divided into three levels:Ⅰ,Ⅱ and Ⅲ.According to the previous research results on the waterrichness evaluation of rock formations and the provisions of the waterrichness classification of aquifers in the Code for Hydrogeological Engineering Geological Exploration of Mining Areas(GB/T 12719-2021),the three levels of each index are calculated and assigned weights one by one according to the analytic hierarchy process and comprehensive index method.The value range is divided into three levels:strong,medium and weak water richness by using isocontour method,which provides scientific basis for the rational development of coalbed methane.
万方数据
维普
