摘要
鉴于当前实验技术难以准确测定页岩中滞留烃总量,为实现对页岩油含油性的精确评价,本研究以苏北盆地H井密闭取心样品为对象,综合运用冷冻热解、多温阶热解、密闭热释与二维核磁共振(2D-NMR)等多种实验手段,系统开展了含油性及可动性实验评价。通过不同贮存时间的热解对比实验与密闭热释实验,确定了阜二段页岩油轻烃恢复系数为1.99;结合抽提前后热解S_(2)峰面积差值,建立了重烃校正公式(0.4526×S_(2)-0.3079),实现了滞留烃总量的准确计算。进一步利用二维核磁共振技术对不同品质原油进行标定,构建了氢核信号量与油质质量之间的标准曲线,实现了含油量的无损、快速测定;并通过洗油前后核磁谱图对比,明确了可动油与吸附油的T2截止值,计算出游离油含量及其占比。实验结果表明,二维核磁共振法测得的含油量与恢复后含油量高度一致,游离油占比与多温阶热解结果也具有良好相关性。本研究建立的“轻烃恢复—重烃校正—核磁标定—可动油识别”技术体系,具有操作相对简便、检测范围广、对样品无损等优点,整体上显著提升了页岩油含油性及可动性评价的准确性与效率,为页岩油甜点识别、储量计算与开发潜力评估提供了重要的实验依据。
Given the difficulty in accurately determining the total amount of retained hydrocarbons in shale with current experimental techniques,this study aims to achieve a precise evaluation of shale oil content.Using sealed core samples from well H in the Subei Basin as the subjects,this study employed multiple experimental methods,including freeze pyrolysis,multi-temperature step pyrolysis,sealed thermal release,and two-dimensional nuclear magnetic resonance(2D-NMR)to systematically evaluate the oil content and mobility.Through comparative pyrolysis experiments at different storage times and sealed thermal release experiments,the light hydrocarbon recovery coefficient for shale oil in the second member of the Funing Formation was determined to be 1.99.Combined with the difference in pyrolysis S_(2) peak areas before and after extraction,a heavy hydrocarbon correction formula was established(0.4526×S_(2)-0.3079),enabling accurate calculation of the total retained hydrocarbons.Furthermore,2D-NMR technology was used to calibrate crude oil of different qualities,and a standard curve between hydrogen nucleus signal intensity and oil mass was established,enabling non-destructive and rapid determination of oil content.By comparing NMR spectra before and after oil washing,the T₂cutoff values for movable and adsorbed oil were identified,facilitating the calculation of free oil content and its proportion.The experimental results showed that the oil content measured by the 2DNMR method was highly consistent with the recovered oil content,and the proportion of free oil showed a good correlation with results from multi-temperature step pyrolysis.The technical framework of“light hydrocarbon recovery-heavy hydrocarbon correction-NMR calibrationmovable oil identification”established in this study offers advantages such as relative operational simplicity,a broad detection range,and non-destructiveness to samples.Overall,it significantly improves the accuracy and efficiency of shale oil content and mobility evaluation,providing crucial experimental support for shale oil sweet spot identification,reserve calculation,and development potential assessment.
作者
姜志高
马晓东
丁安徐
高和群
曾隽
王雨梦
吴艳艳
JIANG Zhigao;MA Xiaodong;DING Anxu;GAO Hequn;ZENG Jun;WANG Yumeng;WU Yanyan(National Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development,Beijing 102206,China;Sinopec Key Laboratory of Shale Oil/Gas Exploration and Production,Beijing 102206,China;Research Institute of Exploration and Development,Sinopec East China Oil&Gas Company,Yangzhou,Jiangsu 225007,China)
出处
《油气藏评价与开发》
北大核心
2026年第2期266-273,共8页
Petroleum Reservoir Evaluation and Development
基金
中国石化科研项目“溱潼凹陷低TOC陆相页岩油勘探开发关键技术”(P23190)。
关键词
页岩油
轻烃恢复
重烃校正
含油性
二维核磁共振(2D-NMR)
shale oil
light hydrocarbon recovery
heavy hydrocarbon correction
oil content
two-dimensional nuclear magnetic resonance(2D-NMR)
