古交区块煤层气井产能特征及主控因素分析OA

Coalbed methane(CBM)resources are abundant in Gujiao Block at the central part of Xishan Coalfield,where the pro-duction capacity of the regional single well varies greatly due to multiple factors,and the large-scale development of CBM faces severe challenges.Aiming at the problems such as insufficient understanding and unclear main control factors of the productivity characteristics of gas well No.8+9 in Gujiao Block,based on the analysis of regional CBM reservoir formation geological back-ground,developing dynamic data and productivity factors,grey correlation analysis was carried out on regional CBM wells from six aspects of burial depth,resource abundance,permeability,sealing condition,coal structure and skin coefficient based on the average daily gas production of a single well,and the correlation degree was sorted.Finally,the main controlling factors of coalbed methane well productivity in Gujiao Block are determined.The research results indicate that the productivity of CBM wells shows strong het-erogeneity,with average of daily gas production in range of 80-1 900 m3/d;the high production wells are mainly distributed in Zhongshe slope zone,Nanshan syncline zone and Longzigou slope zone,while the relative poor production wells distributed in nose-shaped structural zone;the main controlling factors for the productivity of CBM wells include sealing condition,resource abundance and coal structure.Sealing conditions affect the preservation of CBM,resource abundance controls the material basis of CBM,and coal structure affects the permeability conditions of coal reservoirs.Finally,a regional CBM enrichment and high-yield model based on high resource abundance,strong sealing condition and complete coal structure is proposed.This model shows that the key to real-izing the high yield of coalbed methane production wells in Gujiao Block is to find the productive potential area under rich material foundation,favorable cover layer conditions and good seepage channel.