摘要
川南自贡区块构造位置位于四川盆地威远斜坡南翼,为北西—南东向单斜坡。该区目的层上奥陶统五峰组—下志留统龙一;亚段为深水陆棚相富有机质黑色页岩沉积,储层纵向非均质性较强。水平井页岩“甜点段”钻遇程度的不同造成了测试效果的差异。为明确该区页岩最佳靶体纵向分布、指导水平井钻井轨迹跟踪调整,基于地层小层划分,综合运用钻井、录井、测井及分析化验等资料开展储层精细评价,并利用产气剖面资料评价靶体对页岩气水平井产能的影响。研究结果表明:(1)受沉积和构造作用的双重影响,目的层中龙一^(1)_(1)小层下部页岩段为最优的“地质—工程”双“甜点”;(2)生产测井分析表明,龙一^(1)_(1)小层下部具有最高的单位长度产气贡献率,是研究区的最佳靶体;(3)水平井的龙一^(1)_(1)小层下部页岩有效压裂段长是影响自贡区块气井产能的关键因素。该研究成果将自贡区块最佳靶体纵向分布厚度由2~5 m精确到1~2 m,有效支撑了页岩气产能评价工作,为该区块实现页岩气规模效益开发奠定了基础。
Zigong Block,which is located in the southern side of Weiyuan Slope in Sichuan Basin,is a monocline in NW-SE direction.O_(3)w-S_(1)l^(1-1);is the target layer of that block,which develops black shale with rich organic matters in deep-water continental shelf,while the longitudinal heterogeneity of the reservoir is strong.Different penetration degrees in the sweet spot of horizontal shale well lead to different testing results.In order to determine the longitudinal distribution of the optimal shale target and guide the tracking and adjustment of horizontal well drilling trajectory,based on stratigraphic subdivision,fine evaluation of reservoir is carried out by the comprehensive data of drilling,logging,well testing and laboratory analysis.Meanwhile,the gas production profile data are used to evaluate the impact of the target on shale gas productivity of the horizontal wells.The research results show that:(1)Under the influence of both sedimentation and tectonics,the lower part of S_(1)l^(1-1)are the optimal“sweet spots”for both geology and engineering among target layers;(2)The production well logging data indicate that,the lower part of S_(1)l^(1-1)shows highest gas production contribution of per unit length,which is the optimal target position of the research area;(3)The effective fracking length of shale reservoir in the lower part of S_(1)l^(1-1)for horizontal well is the key factor for gas well productivity in Zigong Block.Based on the above results,which supports the productivity evaluation of shale gas effectively,and sets the foundation for realizing large-scale and cost-efficient development of shale gas in that block,the longitudinal distribution thickness of the optimal target in Zigong Block is accurate from 2~5 m to 1~2 m.
作者
张成林
杨学锋
赵圣贤
张鉴
邓飞涌
何沅翰
张德良
王高翔
钟光海
ZHANG Chenglin;YANG Xuefeng;ZHAO Shengxian;ZHANG Jian;DENG Feiyong;HE Yuanhan;ZHANG Deliang;WANG Gaoxiang;ZHONG Guanghai(Shale Gas Institute of PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610051,China;Shale Gas Evaluation and Exploitation Key Laboratory of Sichuan Province,Chengdu,Sichuan 610213,China;Shunan Gas Field of PetroChina Southwest Oil&Gasfield Company,Luzhou,Sichuan 646000,China)
出处
《油气藏评价与开发》
CSCD
2022年第3期496-505,共10页
Petroleum Reservoir Evaluation and Development
基金
中国石油天然气集团公司科技攻关项目“深层页岩气有效开采关键技术攻关与试验—深层页岩气开发优化技术现场试验(任务2)”(2019F-31-02)。
关键词
储层精细评价
产气剖面分析
靶体优选
优质页岩储层
五峰组—龙马溪组
fine evaluation of reservoirs
analysis of gas-production profile
target position optimization
high-quality shale reservoir
Wufeng-Longmaxi Formation
