摘要
含盐储层是一种特殊类型油气藏储层,储层塑性高,盐岩遇水易溶解,压裂后导流能力保持难度大,探究高含盐储层长期导流能力变化规律和岩溶因素是提升油井产量的必要条件。结合玛湖含盐储层“低黏土矿物、低石英、低长石、高盐”的特点,通过开展支撑剂长期导流能力测试实验,测试不同支撑剂的铺置条件、不同岩板的含盐量、不同的流体介质条件下的导流能力变化规律。结果表明:使用大粒径高铺砂浓度支撑剂可显著增加含盐储层的导流能力,高含盐岩板的长期导流能力高于中含盐岩板,清水流体介质驱替裂缝的导流能力高于饱和岩溶液流体介质;建立了含盐储层长期导流能力的预测方法,在考虑支撑剂破碎、塑性嵌入、蠕变作用和岩溶作用的情况下,分别计算支撑裂缝宽度和渗透率以确定导流能力变化规律;计算结果预测值与实验值的吻合度较高,表明了岩溶作用对含盐储层的裂缝宽度以及长期导流能力的提升具有显著效果。研究成果对于高含盐储层长期提升导流能力并实现油气藏的高产稳产具有重要的指导意义。
Saline reservoir is a special type of oil and gas reservoir with high ductility.Saline rock is soluble in wa-ter,and difficult to maintain conductivity after fracturing.Studying long-term variation in conductivity and karst fac-tor of high saline reservoirs is necessary for improving oil well production.Based on characteristics of“low clay min-erals,low quartz,low feldspar,and high salt”in Mahu saline reservoir,long-term conductivity testing experiment is conducted to test laying conditions of different proppants,salt content of different rock plates and conductivity variation of different fluids media conditions.The results show that using large particle size and high laying concen-tration proppant can significantly increase conductivity of saline reservoir.Long-term conductivity of high saline rock plates is higher than that of medium saline rock plates,and conductivity of fresh water fluid media displacing fractures is higher than that of saturated saline solution fluid media.A prediction method for long-term conductivity of saline reservoir is established.Considering proppant fragmentation,ductile embeddings,creep effect and karst effect,propped fracture width and permeability are respectively calculated to determine conductivity variation law.Predicted values of calculation results are highly coincident with experimental values,indicating that karst has sig-nificant effect on improving fracture width and long-term conductivity of saline reservoir.The research has guiding significance for improving conductivity of high saline reservoirs in long term and achieving high and stable produc-tion of oil and gas reservoirs.
作者
李圣祥
王雷
许文俊
廖愿爱
张健鹏
LI Shengxiang;WANG Lei;XU Wenjun;LIAO Yuanai;ZHANG Jianpeng(School of Petroleum Engineering,Yangtze University,Wuhan 430100,China;Hubei Key Laboratory of Drilling and Production Engineering for Oil and Gas,Wuhan 430100,China)
出处
《大庆石油地质与开发》
CAS
北大核心
2024年第5期98-106,共9页
Petroleum Geology & Oilfield Development in Daqing
基金
国家自然科学基金项目“超临界CO_(2)压裂页岩多物理场耦合机理研究”(51804039)。
关键词
盐岩
导流能力
支撑剂
蠕变
岩溶
saline rock
conductivity
proppant
creep
karst
