新疆库拜煤田铁列克矿区地应力分布及其对煤层气开发的影响  

In-situ Stress Distribution and Its Influence on Coalbed Methane Development in Tielieke Mining Area,Kubai Coalfield,Xinjiang

作　　者：魏永恒 葛燕燕 王刚 王文峰 田继军 李鑫 吴斌 张晓 WEI Yongheng;GE Yanyan;WANG Gang;WANG Wenfeng;TIAN Jijun;LI Xin;WU Bin;ZHANG Xiao(College of Geology and Mining Engineering,Xinjiang University,Urumqi,Xinjiang 830047,China;Coalbed Methane Research and Development Center of Xinjiang Coal Geological Exploration Bureau,Urumqi,Xinjiang 830046,China;No.161 Coal Exploration Team,Xinjiang Coal Geological Exploration Bureau,Urumqi,Xinjiang 830046,China)

机构地区：[1]新疆大学地质与矿业工程学院,新疆乌鲁木齐830047 [2]新疆维吾尔自治区煤田地质局煤层气研究开发中心,新疆乌鲁木齐830046 [3]新疆维吾尔自治区煤田地质局一六一地质勘探队,新疆乌鲁木齐830046

出　　处：《现代地质》2022年第5期1324-1332,共9页Geoscience

基　　金：新疆维吾尔自治区自然科学基金项目(2019D01B43);国家自然科学基金项目(U1903303,42002188,42062012)

摘　　要：地应力、煤储层渗透率和煤储层压力等是影响煤层气开发的重要因素。通过分析新疆库拜煤田铁列克矿区注入/压降试井及原地应力测试数据,结合铁列克矿区煤层气井日产气量分析,研究了新疆库拜煤田铁列克矿区地应力变化规律及其对煤层气开发的影响,分析了铁西矿区和铁东矿区煤储层地应力特征及其对煤储层物性的影响。结果表明:(1)地应力状态在垂向上发生变化,埋深处于550~650 m、650~850 m和850~1200 m时,地应力状态类型依次为σ_(H)>σ_(v)>σ_(h)、σ_(H)≈σ_(v)>σ_(h)和σ_(v)>σ_(H)>σ_(h);(2)埋深850 m处既是垂直主应力和最大水平主应力的转换点也是渗透率趋势变化点,指示了地应力对渗透率的控制作用;(3)渗透率和煤储层压力与地应力分别呈负相关和正相关关系;(4)地应力对产能的负效应大于地应力对产能的正效应,使典型日产气量随着地应力的增大而减小;(5)铁西矿区和铁东矿区中部煤储层碎粒煤较发育、吸附孔体积和含气量均较大,是煤层气开发的有利区带。研究成果可为库拜煤田下一步煤层气开发提供理论指导。In-situ stress,coal reservoir permeability and coal reservoir pressure are the important factors on coalbed methane development.Based on the analysis of injection/fall-off well analysis and in-situ stress measurement data,and combined with the analysis of daily gas production of coalbed methane wells in the Tielieke mining area(Kubai coalfield,Xinjiang),we study the characteristics of in-situ stress distribution at Tielieke and its influence on CBM development.The results show that:(1)the in-situ stress state changes vertically,with σ_(H)>σ_(v)>σ_(h)、σ_(H)≈σ_(v)>σ_(h) and σ_(v)>σ_(H)>σ_(h) at 550-650 m,650-850 m and 850-1,200 m reservoir depth,respectively;(2)850 m depth is not only the conversion point of the vertical principal stress and the maximum horizontal principal stress,but also the transition point of permeability trend.This demonstrates the in-situ stress the control on permeability;(3)the in-situ stress correlates negatively with permeability,but positively with coal reservoir pressure;(4)for the in-situ stress,its negative effect of on productivity is greater than its positive effect on productivity,and hence the typical daily gas production decrease with increasing in-situ stress;(5)the central coal reservoirs in Tiexi and Tiedong mining areas have relatively developed granular coal,large adsorption pore volume and gas content,which are favorable intervals for CBM development.Our results provide theoretical guidance for further CBM development in the Kubai coalfield.

关 键 词：煤层气 地应力 煤储层渗透率 煤储层压力 含气量 铁列克矿区 

分 类 号：P618.11[天文地球—矿床学] P553[天文地球—地质学]