天赐湾地区长4+5油层组薄油层有效储层下限测井评价  

Log Evaluation of Effective Reservoir Lower Limit of Thin Oil Layer of Chang 4+5 Oil Formation in Tianciwan Area

作　　者：李鹏勃[1] 周冕[1] 高路遥 张佳磊 LI Pengbo;ZHOU Mian;GAO Luyao;ZHANG Jialei(Jingbian Oil Production Plant,Yanchang Oilfield Co.LTD.,Yulin,Shaanxi 718500,China;China Railway Wuju Group Materials Industrial Co.LTD.,Xi’an,Shaanxi 710061,China)

机构地区：[1]延长油田股份有限公司靖边采油厂,陕西榆林718500 [2]中铁五局集团物资实业有限责任公司,陕西西安710061

出　　处：《测井技术》2024年第2期230-239,共10页Well Logging Technology

基　　金：延长油田股份有限公司项目“靖边油田天赐湾区三叠系延长组长4+5、长6油层组石油探明储量”(YT20KT-009-19)。

摘　　要：为实现鄂尔多斯盆地天赐湾地区长4+5油层组薄油层的精细刻画,需要开展系统的有效储层下限综合评价。利用该地区主力油层长4+5^(2)亚段大量地质、实验、测井、生产资料,系统研究了致密油藏储层特征并提出有效储层下限标准。研究结果表明,工区长4+52亚段储层的岩性以细粒长石砂岩为主,砂岩粒度曲线具有2段式特征。孔隙度主要分布在8%~16%,峰值区间分布在10%~13%;渗透率主要分布在0.2~5.6 mD^(*),存在2个峰值区间,分别为0.3~0.4 mD及1.4~5.6 mD。渗透率高于1.0 mD的相对高渗优质储层的平均孔喉半径大于0.14μm且分选系数大于2.5。长4+52亚段有效储层的含油级别为油迹级及油斑级,物性下限标准为孔隙度9.0%、渗透率0.3 mD。此外,储层有效厚度电性参数,包括测井孔隙度、含油饱和度、电阻率及声波时差的下限分别为9.0%、40.0%、15Ω・m及225μs/m。结合岩心、测试、测井及试油资料构建的致密油油水层识别标准在薄油层应用中是可靠的。A systematic and comprehensive evaluation of the lower limit of the effective reservoir is needed to realize the fine engraving of the thin oil reservoir in the Chang 4+5 oil formation group in the Tianciwan area of the Ordos basin.In this paper,the characteristics of tight reservoir and the lower limit standard of effective reservoir are systematically studied by using a large amount of geological,experimental,well logging and production data of Chang 4+52 oil formation in this area.The results show that the Chang 4+5^(2)oil formation mainly develops light gray and gray white fine-grained arkose,and the grain size curve of the sandstone has two-stage characteristics.The porosity is mainly distributed in 8%~16%,and the peak interval is distributed in 10%~13%.The permeability is mainly distributed in 0.2~5.6 mD,and there are two peak intervals,which are 0.3~0.4 mD and 1.4~5.6 mD,respectively.The average pore radius of the relatively high-permeability high-quality reservoirs with the permeability higher than 1.0 mD is higher than 0.14μm,and the sorting coefficient is higher than 2.5.The lower limit of effective reservoir oil grade is oil trace grade,and the lower limit of reservoir physical property is:permeability of 0.3 mD and porosity of 9.0%.The lower limits of electrical parameters of effective thickness are as follows:porosity≥9.0%;oil saturation≥40.0%;resistivity≥15Ω・m;the acoustic wave time difference is more than 225μs/m.The reservoir identification criteria for tight oil constructed in this paper by combining core,test,logging,and oil test data are reliable in thin reservoir applications.

关 键 词：测井评价 鄂尔多斯盆地天赐湾地区 长4+5^(2)亚段 有效储层下限 评价标准 

分 类 号：P631.84[天文地球—地质矿产勘探]