摘要
四川盆地自贡地区是目前下志留统龙马溪组页岩气勘探的重点区块,针对该区部署的第1批水平井测试效果不理想,平均单井测试日产气量仅为7.6×10^(4)m^(3)/d。后期通过地质工程一体化相结合,综合评价目的靶层,有针对性地调整水平井靶体位置,实现了最新批次水平井测试产气量的大幅度提升。针对自贡地区龙马溪组高硅质页岩段定量评价及靶体调整的主要研究思路为:①基于地质工程一体化进行甜点层评价,进一步明确研究区龙一11小层为水平井部署的最佳甜点层。②根据高硅质页岩段划分标准,创新性地将龙一11小层纵向上划分为顶部、中部和底部3个层段,并重点针对高硅质页岩段进行精细储层评价,明确高硅质层段在含气性、脆性和可压性等方面具有明显的优势,可作为最优靶体部位。③对比靶体调整前后单井日产气量提升2.6倍,调整前测试日产气量为7.64×10^(4)m^(3)/d,调整后测试日产气量为20.01×10^(4)m^(3)/d,充分论证了研究区以富碳高硅质页岩段为靶体调整目标的最优解。以水平井靶体调整的方向为主线,系统分析了龙一11小层中下部高硅质页岩段的储层条件,并通过下沉靶体部位实现了产气量的提升。
Zigong area of Sichuan Basin is the main battlefield of shale gas exploration in the Lower Silurian Longmaxi For⁃mation.The test results of the first batch of horizontal wells deployed in this area are not ideal,and the average test produc⁃tion of a single well is only 7.6×10^(4)m^(3)/d.The test production of the latest batch of horizontal wells has been greatly im⁃proved by employing geology-engineering integration,conducting a comprehensive evaluation of target layers,and pointed⁃ly adjusting the target position.The following are the main research ideas for the quantitative evaluation and target adjust⁃ment of the high-silica shale sections of Longmaxi Formation in Zigong area.Firstly,the“sweet spot”layers are evaluated on the basis of geology-engineering integration,and Long11 sublayer is confirmed to be the best“sweet spot”layer for hori⁃zontal well deployment.Secondly,according to the classification standard of a high-silica shale section,Long11 sublayer is innovatively divided into an upper section,a medium section,and a lower section vertically.Fine reservoir evaluation is conducted mainly on the high-silica shale sections.It is clarified that the high-silica sections,with obvious advantages in gas-bearing property,brittleness,fracturing ability,etc.,can be used as the optimal target position.Thirdly,the single-well daily gas production after target adjustment is 20.01×10^(4)m^(3)/d,which is 2.6 times the value before target adjustment(7.64×10^(4)m^(3)/d).This result fully demonstrates that the carbon-rich and high-silica shale sections are the optimal solutions of tar⁃get adjustment in this area.With the target adjustment direction of horizontal wells as the thread,this paper systematically expounds the reservoir conditions of the high-silica shale sections in the middle-low Long11 sublayer and increases the gas production by lowering the target position.
作者
胡浩
赵文韬
张爱华
凡田友
郭富凤
邹翔
刘文磊
陈怡
HU Hao;ZHAO Wentao;ZHANG Aihua;FAN Tianyou;GUO Fufeng;ZOU Xiang;LIU Wenlei;CHEN Yi(Shunan Gas Mine,Petro China Southwest Oil&Gasfield Company,Luzhou City,Sichuan Province,646000,China)
出处
《油气地质与采收率》
CAS
CSCD
北大核心
2022年第4期25-34,共10页
Petroleum Geology and Recovery Efficiency
基金
重庆市教委科学技术研究项目“基于谱蓝化有色反演技术的页岩气薄储层预测”(KJQN201801520)。
关键词
龙马溪组
页岩
甜点层
高硅质页岩段
川南地区
Longmaxi Formation
shale
sweet spot layer
high-silica shale section
southern Sichuan Basin
