页岩储层构造裂缝活动期次及开启性研究进展与展望  

Tectonic fracturing and fracture initiation in shale reservoirs—research progress and outlooks

作　　者：丁文龙[1,2,3] 王垚 张子游 刘天顺 程晓云 勾通 王生晖 刘霆锋 DING Wenlong;WANG Yao;ZHANG Ziyou;LIU Tianshun;CHENG Xiaoyun;GOU Tong;WANG Shenghui;LIU Tingfeng(School of Energy Resources,China University of Geosciences(Beijing),Beijing 100083,China;Key Laboratory for Marine Reservoir Evolution and Hydrocarbon Abundance Mechanism,Ministry of Education,China University of Geosciences(Beijing),Beijing 100083,China;Key Laboratory of Strategy Evaluation for Shale Gas,Ministry of Natural Resources of the People’s Republic of China,China University of Geosciences(Beijing),Beijing 100083,China)

机构地区：[1]中国地质大学(北京)能源学院,北京100083 [2]中国地质大学(北京)海相储层演化与油气富集机理教育部重点实验室,北京100083 [3]中国地质大学(北京)自然资源部页岩气资源战略评价重点实验室,北京100083

出　　处：《地学前缘》2024年第5期1-16,共16页Earth Science Frontiers

基　　金：国家自然科学基金面上项目(42072173,42372171)。

摘　　要：随着我国在非常规油气领域的研究不断深入和技术手段不断提高,页岩油气勘探开发工作取得了显著进展。大量生产实践结果表明:页岩储层裂缝是影响油气富集、高产和稳产的关键因素,页岩储层中裂缝的存在不仅可以改善储层的物性,还有利于后期的压裂改造。特别是储层中发育的构造裂缝,其活动期次与开启性的研究对于揭示页岩油气富集规律、保存条件等具有重要意义。早期对于页岩储层裂缝的研究集中在裂缝分类、识别与表征、裂缝发育主控因素分析与分布预测及建模等方面,而对于裂缝的形成时间与活动期次厘定、裂缝开启性的主控因素、裂缝开启与闭合机理、裂缝开启程度定量表征研究相对薄弱,制约了我国盆内页岩油气的高效勘探开发。为此本文在充分调研了国内外页岩储层构造裂缝研究成果的基础上,围绕页岩储层构造裂缝活动期次及开启性这一主题,重点梳理了页岩裂缝期次划分、充填脉体定年、开启性主控因素分析及开启程度定量表征方面的研究进展。裂缝活动期次的划分方法可分为两类:地质定性分析和裂缝充填物地球化学示踪分析。在实际应用中,上述方法只能得到裂缝活动期次相对的先后顺序,且会受到埋藏史、热史等基础地质资料精度的影响,其应用存在一定局限性。裂缝中脉体多为碳酸盐岩矿物和石英,高精度微区原位U-Pb定年技术的出现,使得厘定不同组系裂缝脉体形成的绝对年龄成为可能,避免了由于热史、埋藏史认识差异带来的流体活动时间的多解问题。影响构造裂缝开启性的主控因素较多,不仅受到岩石本身特性的影响,还受到现今地应力、地层流体压力等因素的控制。裂缝中广泛分布的纤维状充填物岩石学特征记录了晶体的生长过程,此类特殊的晶体形态是裂缝曾经存在多期活动的证据,揭示了裂缝多次开�Shale oil and gas development has gained significant progress in China with the contineous research and technological advancements in unconventional oil and gas.Extensive production practices demonstrate that natural fracture development in shale reservoirs is a crucial factor influencing oil and gas enrichment,high production and stable yield,for fractures not only improve reservoir properties but also facilitate subsequent reservoir modification during hydrollic fracturing.The formation stages of tectonic fractures and fracture initiation holds significant importance for revealing the oil and gas enrichment patterns and preservation condition.Early studies on shale reservoir fractures mainly focused on fracture classification/identification/characterization,main controlling factors of fracture development,and fracture distribution prediction and modelling,with less attention to the determination of fracture formation stages,main controlling factors of fracture initiation,mechanism of fracture opening and closing,and quantitative characterization of fracture openness—this restricts the efficient exploration and development of shale oil and gas in China.This paper highlights research progress addressing the above gaps,particularly the delineation of fracturing stages,dating of filling veins,and quantification of fracture openness based on comprehensive literature review.The classification methods for fracturing stages can be divided into two categories:qualitative geological analysis and geochemical tracing of fracture fillings.These methods however have practical limitations,where only the relative sequence of fracturing stages can be obtained,and the results are affected by the accuracy of basic geological data such as burial/thermal histories.Most of the fissure veins in fractures are carbonate minerals and quartz.With the advent of high precision in situ U-Pb microprobe dating technology,it is possible to determine the absolute ages of different veins while avoiding the problem of multiple solutions to flui

关 键 词：页岩储层 构造裂缝 活动期次 裂缝开启性 裂缝脉体 定量表征 

分 类 号：P618.130.2[天文地球—矿床学]