页岩油储层D—T2核磁共振解释方法  

Discuss on D-T NMR interpretation of oil shale

作　　者：王志战 WANG Zhi-zhan(State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development,Beijing 100101,China;Sinopec Research Institute of Petroleum Engineering,Beijing 100101,China)

机构地区：[1]页岩油气富集机理与有效开发国家重点实验室,北京100101 [2]中国石化石油工程技术研究院测录井研究所,北京100101

出　　处：《天然气地球科学》2020年第8期1178-1184,共7页Natural Gas Geoscience

基　　金：页岩油气富集机理与有效开发国家重点实验室开放基金(编号:P17014-9);国家自然科学基金(编号:21427812);中国石化科技部项目(编号:P14095);中国石化油田勘探开发事业部项目(编号:YTXD-PT1203D);中国石化石油工程技术服务有限公司项目(编号:SG16-46X)联合资助.

摘　　要：D—T2二维核磁共振能够快速、直观地区分不同性质、不同赋存状态的孔隙流体,已成为储层评价的热门技术,但对于页岩油储层,常规储层的D—T2孔隙流体解释图版并不适用,考虑受限扩散、内部梯度等影响因素的修正图版也难以满足页岩油储层油、水识别的要求。为此,采用理论分析与实验分析相结合的方法,对D—T2孔喉尺度分辨率、流体含量分辨率、孔隙流体解释图版3个关键要素进行了深入研究。结果表明,D—T2孔喉尺度分辨率、流体含量分辨率均低于T2一维核磁共振,难以检测到T2短于2 ms、含量低于0.2%的流体信号;D—T2信号位置与流体含量有关,且随着流体含量的递增,具有随机游走特性。2口页岩油井的应用表明,基于流体含量信号响应轨迹的D—T2流体解释图版能够实现页岩油储层的准确解释。D-T2 two-dimensional nuclear magnetic resonance(NMR)could quickly and visually distinguish dif⁃ferent type,different occurrence state of pore fluid,and become the hot technology for reservoir evaluation,but for oil shale,D-T2 pore fluid interpretation chart of conventional reservoir is not suitable.The correction chart,considering restricted diffusion,internal gradient,etc.,is also difficult to meet the requirements of oil and water recognition in oil shale.Therefore,three key scientific problems of D-T2 pore throat scale resolution,fluid con⁃tent resolution and pore fluid interpretation chart are studied by combining theoretical analysis and experimental analysis.The results show that the pore throat scale resolution and fluid content resolution of D-T2 NMR was lower than that of T2 NMR,and it was difficult to detect the fluid signal with T2 shorter than 0.2ms and content less than 0.2%.The location of D-T2 signal is related to fluid content and has a random walk property as fluid content increases.The applications of two shale oil wells show that the D-T2 fluid interpretation chart based on the signal response trajectory can achieve accurate interpretation of oil shale.

关 键 词：D—T2核磁共振 页岩油储层 油水识别 分辨率 解释图版 

分 类 号：TE132.14[石油与天然气工程—油气勘探]