陆东凹陷中低成熟度页岩油储层含油性特征及“甜点”评价  

Oil-bearing Characteristics and"Sweet Spots"Evaluation of Medium-low Maturity Shale Oil Reservoirs in Ludong Sag

作　　者：周立国[1] Zhou Liguo(PetroChina Liaohe Oilfield Company,Panjin,Liaoning 124010,China)

机构地区：[1]中国石油辽河油田分公司,辽宁盘锦124010

出　　处：《特种油气藏》2024年第4期27-35,共9页Special Oil & Gas Reservoirs

基　　金：中国石油天然气股份有限公司重大科技专项“辽河油田千万吨稳产关键技术研究与应用”(2017E-16)。

摘　　要：针对陆东凹陷交力格洼陷中低成熟度页岩油储层分布特征与富集控制因素不明等问题,通过开展二维核磁共振分析、纳米CT扫描、干酪根显微组分鉴定等方法,对页岩油储层含油性特征进行研究,综合页岩岩相、储集性、含油性及可动性等因素,基于储层及含油性分级参数建立了页岩油“甜点”综合评价标准。结果表明:页岩纹层与层理的发育程度、密度、岩性等结构特征是含油性特征及分布的主要影响因素。层状含粗粒岩屑粉砂岩与纹层状长英质页岩岩相微观孔隙结构及连通性较好,比表面积小于15 m 2/g,氮气吸附平均孔径大于8 nm,为优质储层。Ⅰ+Ⅱ类“甜点”TOC大于1%,储层发育中、大孔,占比大于25%,储集空间孔径大于8 nm,含油性和可动性为中等—好,油气相对富集。该成果可为研究区页岩油有利目标优选及试验区部署评价提供技术支撑。To address the issues of unclear distribution characteristics and enrichment control factors of medium-low maturity shale oil reservoirs in the Jiaolige Sag,Ludong Depression,a study on the oil-bearing characteristics of shale oil reservoirs was conducted through methods such as 2D NMR analysis,nano-CT scanning,and identification of kerogen microscopic components.A comprehensive evaluation standard for identifying shale oil sweet spots was established based on factors such as shale lithofacies,reservoircapabilities,oil-bearing characteristics,andmobility.The results show that the degree of development,density,lithology,and other structural characteristics of shale lamination and bedding are the primary influencing factors on the oil-bearing characteristics and distribution.The layered siltstone,composed of coarse grained clastics and laminated felsic shale,exhibits excellent pore microstructure and connectivity.The specific surface area is less than 15 m 2/g,and the average pore size of nitrogen adsorption is greater than 8 nm,which is a highly favorable reservoir.The total organic carbon(TOC)content of classⅠ+Ⅱ"sweet spot"exceeds 1%,with the reservoir exhibiting medium and large pores accounting for over 25%.The pore size within the reservoir space is greater than 8 nm,indicating a medium to good oil bearing potential and mobility,leading to relatively enriched oil and gas.These findings offer valuable technical support for identifying favorable targets for shale oil development in the study area,as well as for deploying and evaluating test areas.

关 键 词：“甜点”评价 赋存特征 微观分布 中低成熟度 页岩油 交力格洼陷 陆东凹陷 

分 类 号：TE122[石油与天然气工程—油气勘探]