致密气不同类型甜点对水平井压裂产能影响规律  

Effects of Different Types of Tight Gas Sweet Spots onHorizontal Well Fracturing Productivity

作　　者：江锚 吴建树 彭成勇 马伟云 白玉湖 杨帆 JIANG Mao;WU Jian-shu;PENG Cheng-yong;MA Wei-yun;BAI Yu-hu;YANG Fan(CNOOC Research Institute Co.,Ltd.,Beijing 100028,China;State Key Laboratory of Offshore Oil andGas Exploitation,Beijing 102209,China;China United Coal Bed Methane Co.,Ltd.,Beijing 100011,China)

机构地区：[1]中海油研究总院有限责任公司,北京100028 [2]海洋油气高效开发全国重点实验室,北京102209 [3]中联煤层气有限责任公司,北京100011

出　　处：《科学技术与工程》2025年第11期4515-4525,共11页Science Technology and Engineering

基　　金：国家自然科学基金(42130803,51704324)。

摘　　要：致密砂岩储层孔喉半径偏小,启动压力梯度偏高,地层物性差,压裂施工后的水平井产气量差异大,严重影响着致密气的增储上产。针对上述问题,分析了鄂尔多斯东缘盆地不同级别甜点下的气井生产动态,并提出了基于甜点展布的致密气压裂新方法。在岩石力学参数、储能系数及泥质含量参数评价的基础上,建立地质甜点及工程甜点评价模型,运用模糊综合评判方法划分了致密砂岩气藏储层品质。根据不同的甜点类型组合,总结了Ⅰ、Ⅱ、Ⅲ类水平井生产特征及甜点分布特征,形成了基于地质甜点工程甜点的3类压裂模式。结果表明:当水平井钻遇Ⅰ类地质甜点及Ⅰ类工程甜点时,则累计产气量高于预期(Ⅰ类井),可采用较大的压裂规模及排量,追求经济效益最大化(模式1);当水平井钻遇Ⅰ类地质甜点及Ⅱ类以下工程甜点组合时,其累计产气量低于Ⅰ类井(Ⅱ类井),压裂规模应适当降低,追求一定的产能和经济效益(模式2);当水平井钻遇Ⅱ类以下地质甜点及Ⅰ/Ⅱ类工程甜点组合时,生产效果最差(Ⅲ类井),需降低排量控制压裂规模,避免裂缝窜入风险层,获得一定的产能(模式3)。上述压裂新方法应用于致密气藏一口新钻水平井中,该水平井压后无阻流量及产气量均达到预期,对致密砂岩气藏的开发具有一定的指导意义。The small pore throat radius,high starting pressure gradient,poor formation physical property and large gas production difference of horizontal wells after fracturing in tight sandstone reservoirs seriously affect the increase of tight gas reserves and production.In view of the above problems,the production dynamics of gas wells under different levels of sweet spots in the eastern Ordos Basin were analyzed,and a new tight gas fracturing method based on sweet spot distribution was proposed.Based on the evaluation of rock mechanics parameters,energy storage coefficient and argillaceous content parameters,the evaluation model of geological sweet spot and engineering sweet spot was established,and the reservoir quality of tight sandstone gas reservoir was divided by fuzzy comprehensive evaluation method.According to different sweet spot types,the production characteristics and sweet spot distribution characteristics of Class I,II and III horizontal wells were summarized,and three fracturing modes based on geological sweet spot and engineering sweet spot were formed.The results show that when the horizontal well is drilled in Class I geological sweet spot and Class I engineering sweet spot,the cumulative gas production is higher than expected(Class I well),and a larger fracturing scale and displacement can be adopted to maximize the economic benefit(Model 1).When the horizontal well is drilled in Class I geological sweet spot and Class II engineering sweet spot combination,the cumulative gas production is lower than Class I well(Class II well),and the fracturing scale should be reduced appropriately to pursue a certain production capacity and economic benefit(Model 2).When horizontal wells are drilled in geological sweet spots below Class II and combinations of Class I/II engineering sweet spots,the production effect is the worst(Class III wells),and the fracturing scale should be controlled by reducing displacement to avoid the fracture from entering the risk layer and obtain a certain production rate(Model 3).The ab

关 键 词：致密气 地质甜点 工程甜点 累计产气量 分段分簇优化 压裂规模优化 

分 类 号：TE377[石油与天然气工程—油气田开发工程]