摘要
针对低缓构造背景下碳酸盐岩气藏气水分布精细描述既是研究的重点也是亟待突破的难点,它直接关系着气田开发井部署的成功率,也是生产优化调整的重要地质依据,但传统的气水描述方法存在一些局限,尚不能完全满足目前精细开发的需求。为此,以四川盆地磨溪龙王庙组气藏为研究对象,综合古今构造特征及成藏演化过程,在充分剖析气水分布控制因素的基础上,建立低缓构造背景下气水分布模式,揭示气藏气水分布规律,研究取得以下几点认识:①研究区现今构造特征总体表现为地层倾角低、闭合度小、闭合面积大及圈闭内多高点,古地貌格局表现为西高东低、三区分带,为现今气水分布研究奠定基础。②气水分布受控于现今构造、古构造、岩性及不整合面等多重因素,当位于古、今构造高部位和溶蚀孔洞储层发育区,油气富集性最好;位于古今构造低部位的储层发育区,则易形成富水区。③采用建立过渡区气水分布模型研究大型低缓构造气水分布,阐明过渡区与气水过渡带之间的关系,建立不同地层倾角条件下过渡区占比总含气面积的分析模型,当地层倾角小于5°时,过渡区所占含气面积比重较大,最大可超过50%。④按照水体对生产影响程度描述活跃水体和不活跃水体,剖析对生产可能造成的影响,提出需针对性制定对策以预防水体快速侵入气区影响正常生产。
For carbonate-rock gas reservoirs in low and gentle structures,a fine description on their gas-water distribution has always been a focus of research and a difficulty to be solved.Furthermore,it directly affects success rate of development-well deployment,and is also an important geological basis for production optimization and adjustment.However,owing to limitation,those traditional methods to describe gas and water cannot fully meet the need of current fine development.So,taking gas reservoirs of Longwangmiao Formation,Moxi area,Sichuan Basin,as a research object,we established a gas-water distribution pattern for low and gentle structures,and revealed its distribution law after analyzing some controlling factors according to not only characteristics of ancient and modern structures but also the evolution of hydrocarbon accumulation.Some knowledge was gained,①the modern structure is characterized by small formation dip,low closure,large closed area,and multiple high position existing in trap,presenting a three-zone in paleogeomorphic pattern and ascending from east to west;②gas-water distribution is controlled by multiple factors including modern and ancient structures,lithology,and unconformity.The best hydrocarbon accumulation is in the higher part of ancient and modern structures and in some reservoirs with developed solution pores.And an area with rich water tends to form at a reservoir development zone which is located in the lower part of ancient and modern structures;③a gas-water distribution model for transition zones is used to study its distribution in large-scale low and gentle structures,the relationship between the transition zone and the gas-water transition zone is clarified,and an analysis model to calculate the proportion of transition zone in whole gas-bearing area under different formation dip is established.It is shown,when formation dip is less than 50,the proportion of transition zone is higher,and the maximum can exceed 50%;and④it is recommended to describe active and inactive wat
作者
张春
彭先
李骞
王蓓
郭鸿喜
Zhang Chun;Peng Xian;Li Qian;Wang Bei;Guo Hongxi(Key Sub Laboratory of Carbonate Gas Reservoir Formation Mechanism Key laboratory of Gas Reservoir Formationand production.CNPC;Exploration Department,PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610041,China)
出处
《天然气勘探与开发》
2019年第1期49-57,共9页
Natural Gas Exploration and Development
基金
"十三五"国家科技重大专项"四川盆地大型碳酸盐岩气田开发示范工程"(编号:2016ZX05052)
中国石油天然气股份公司重大科技专项"西南油气田天然气上产300×10~8 m~3关键技术研究与应用"(编号:2016E-0605)
关键词
大型低缓构造
碳酸盐岩气藏
气水分布
古构造
控制因素
精细描述
Large-scale low and gentle structure
Carbonate-rock gas reservoir
Gas-water Distribution
Ancient structure
Controlling factor
Fine description
