中国陆相页岩油研究进展与关键科学问题

中国陆相盆地页岩油资源丰富，是中国油气增储上产的重要战略接替领域。限于陆相盆地特殊复杂的地质条件，陆相页岩油的富集规律与主控因素不够明确，中国陆相页岩油勘探所面临的关键科学问题仍然有待进一步研究。通过充分调研国内外以细粒沉积、烃类赋存以及流体运移为重点研究页岩油的最新进展，结合中国陆相页岩油勘探进展，对比总结了陆相和海相页岩油的基础地质特征及其差异，提出了目前中国陆相页岩油勘探面临的关键科学问题。研究结果表明：中国陆相盆地发育多套页岩油，陆相泥页岩层系具有沉积相变快、沉积厚度大、成熟度较低、黏土矿物含量高的特点；与海相地层相比，沉积构造背景较不稳定，沉积年代较新、非均质性更强，地层能量和地温梯度较低、烃类流体黏度和密度较大。细粒组分形成及地质事件的成因机制不仅是沉积地质学关注的"成源"与地球系统演化的事件信息，也是页岩"成储"及源-储耦合机制研究的关键内容。页岩油的赋存机制与其可动性密切相关，明确赋存机制是优选甜点的关键。微运移机制是页岩油藏开发的基础，随着微流体流动理论、计算机分子模拟与实验技术的发展，其运移机理将会得到进一步揭示。3个关键科学问题为：①细粒沉积岩的形成机理；②陆相页岩油的赋存机制；③陆相页岩油的微运移机制。建议以这3个科学问题为导向，加大地质-工程一体化研究与技术攻关，使其成为中国陆相页岩油革命成功的保障。

Research progress and key scientific issues of continental shale oil in China

China's continental basins are rich in shale oil resources and thus are an important strategic replacement field for increasing oil and gas reserves and production. Limited by the special and complex geological conditions of continental basins, the enrichment rules and main controlling factors of continental shale oil are not clear enough, and the key scientific issues faced in continental shale oil exploration still need to be further studied. Through a thorough investigation of the latest developments in the foreign and domestic researches focusing on the fine-grained sedimentation, hydrocarbon occurrence, and fluid migration of shale oil, in combination with the progress of China's continental shale oil exploration, this paper summarizes the basic geological characteristics and differences in continental and marine shale oil, and proposes the key scientific issues faced in continental shale oil exploration in China. The research results show that there are many sets of shale oil developed in the continental basins of China; the continental shale series of strata are characterized by rapid changes in sedimentary facies, large deposition thickness, low maturity, and high clay mineral content; compared with marine strata, the sedimentary structure background is relatively unstable, the sedimentation age is newer, the heterogeneity is stronger, the stratum energy and geothermal gradient are lower, and the viscosity and density of hydrocarbon fluid are higher. The formation of fine-grained components and the genetic mechanism of geological events are not only the event information of the source formation and the evolution of earth system that sedimentary geology pays attention to, but also the key content of the study of reservoir formation and source-reservoir coupling mechanism for shale. The occurrence mechanism of shale oil is closely related to its mobility, and clarifying the occurrence mechanism is the key to optimizing sweet spots. The micro-migration mechanism is the basis of shale reservoir development. With the development of the micro fluid flow theory, computer molecular simulation and experimental technology, the migration mechanism will be further revealed. The three key scientific issues are the formation mechanism of fine-grained sedimentary rocks, the occurrence mechanism of continental shale oil and the micro-migration mechanism of continental shale oil. It is suggested that these three scientific issues should be taken as the guide, and the integration of geology-engineering research and technical research should be strengthened to make it a guarantee for the success of China's continental shale oil revolution.