LH油田底水发育储层压裂方式模拟研究  

Simulation study on fracturing mode of reservoirs developed in bottom water development of LH oilfield

作　　者：程佳 宋爱莉 孙常伟 江任开 谷悦 CHENG Jia;SONG Aili;SUN Changwei;JIANG Renkai;GU Yue(CNOOC(China)Co.,Ltd.Shenzhen Branch,Guangdong Shenzhen 518067,China;Engineering Technology Branch of CNOOC Energy Development Co.,Ltd.,Tianjin 300452,China)

机构地区：[1]中海石油(中国)有限公司深圳分公司,广东深圳518067 [2]中海油能源发展股份有限公司工程技术分公司,天津300452

出　　处：《非常规油气》2023年第6期88-94,共7页Unconventional Oil & Gas

基　　金：中海石油(中国)有限公司综合科研课题“南海东部生物礁灰岩油田提高采收率研究”(YXKY2015SZ01)。

摘　　要：为了有效开发LH油田产油能力较差的储层,针对LH油田X区礁灰岩储层物性差、天然裂缝发育以及底水发育等特征,在分析目标储层地质特征和物性条件的基础上,对压裂方法进行了模拟研究,分别开展了小规模酸压、小规模水力压裂及控缝高水力压裂在不同施工规模条件下的裂缝形态模拟研究。结果表明:1)LH油田X储层底水距离20~30m,储层无岩性隔层,隔层应力差小于2MPa,常规压裂酸压工艺沟通底水风险大。2)酸压工艺无法控制缝高,当采用小于1m^(3)/min的小排量酸压时,酸蚀缝高发育90m,沟通底水影响压裂效果。3)降低施工规模进行压裂可以限制支撑缝高发育,但最低可降至42.3m,无法达到防止沟通底水的目的。4采用人工隔层的控缝高水力压裂工艺,采用76m^(3)压裂液、9.1t支撑剂和2m^(3)/min排量进行施工,并加入200目粉末陶瓷,建立大于7MPa的隔层应力差,裂缝高度发育为16.2m,可以在不沟通底水的情况下进行压裂改造;通过产能分析,累计产量增加75.8%。以上成果认识,对LH油田底水发育的X储层增产开发具有一定指导意义。In order to effectively develop the reservoir with poor oil production capacity in LH oilfield,aiming at the characteristics of poor physical properties,natural fracture development and bottom water development of reef lime-stone reservoir in X area of LH oilfield,based on the analysis of the geological characteristics and physical conditions of the target reservoir,and conducts a simulation study on fracturing methods.The crack morphology simulation of small-scale acid pressing,small-scale hydraulic fracturing and controlled high-hydraulic fracturing under different construction scales was carried out.The results show that:1)The bottom water distance of X reservoir in LH oilfield is 20~30 m,there is no lithologic barrier in the reservoir,and the stress difference of the barrier is less than 2 MPa,so conventional fracturing acid pressing process poses a high risk to communicate with bottom water.2)The crack height can not be controlled by acid pressing process,and the height of the acid etched crack is 90 m when the small displacement of acid pressing is less than 1 m^(3)/min,which affects the fracturing effect.3)Fracturing at lower construction scale can limit the development of the support joint height,but it can be reduced to a minimum of 42.3 m,which cannot achieve the purpose of preventing communication with the bottom water.4)The controlled joint high hydraulic fracturing process of artificial interlayer was adopted.76 m^(3) fracturing fluid,9.1 t proppant and 2 m^(3)/min displacement were used for construction,and 2o0 mesh powder ceramics were added to establish a stress difference of the interlayer greater than 7 MPa,and the fracture height was 16.2 m,which could be fractured with-out communication with the bottom water.Through capacity analysis,the cumulative output increased by 75.8%.The above results have certain guiding significance for the stimulation and development of X reservoir with developed bottom water in LH oilfield.

关 键 词：底水发育 压裂方式 应力差 控缝高 

分 类 号：P618.13[天文地球—矿床学]