新疆石油地质 ›› 2025, Vol. 46 ›› Issue (6): 668-683.doi: 10.7657/XJPG20250603

• 油气勘探 • 上一篇    下一篇

陆相纹层型页岩油源储耦合与甜点形成机理——以准噶尔盆地风城组为例

曹剑1(), 秦志军2, 魏超1, 向宝力2,3, 刘金1,2,3   

  1. 1.南京大学 地球科学与工程学院,南京 210023
    2.中国石油 新疆油田分公司 勘探开发研究院,新疆 克拉玛依 834000
    3.新疆页岩油勘探开发重点实验室,新疆 克拉玛依 834000
  • 收稿日期:2025-11-02 修回日期:2025-11-13 出版日期:2025-12-01 发布日期:2025-12-05
  • 作者简介:曹剑(1978-),男,江苏泰县人,教授,博士生导师,博士,石油地质学和有机地球化学,(Email)jcao@nju.edu.cn
  • 基金资助:
    国家自然科学基金(42230808);国家重点研发计划(2024YFF0808100);国家油气重大专项(2025ZD1400300)

Source-Reservoir Coupling and Sweet Spot Formation Mechanism of Continental Laminated Shale Oil: A Case Study of the Fengcheng Formation, Junggar Basin

CAO Jian1(), QIN Zhijun2, WEI Chao1, XIANG Baoli2,3, LIU Jin1,2,3   

  1. 1. School of Earth Sciences and Engineering, Nanjing University, Nanjing, Jiangsu 210023, China
    2. Research Institute of Exploration and Development, Xinjiang Oilfield Company, PetroChina, Karamay, Xinjiang 834000, China
    3. Xinjiang Key Laboratory of Shale Oil Exploration and Development, Karamay, Xinjiang 834000, China
  • Received:2025-11-02 Revised:2025-11-13 Online:2025-12-01 Published:2025-12-05

摘要:

中国陆相页岩油已获重大突破,但陆相页岩普遍非均质性强,源储耦合关系复杂,页岩油甜点形成机理仍不够明确。以准噶尔盆地风城组为例,综合运用大视域薄片扫描、场发射扫描电镜-能谱分析、激光共聚焦观测、有机地球化学分析等技术,重点从页岩纹层特征及其对页岩油甜点的控制开展研究。结果表明,以风城组为代表的陆相页岩纹层发育,可划分为粉砂级长英质纹层、泥级长英质纹层、粉晶白云质纹层、粉晶方解石纹层、球粒状硅质纹层和碱类矿物纹层6种类型,主要有粉砂级+泥级长英质纹层和粉晶方解石/白云质纹层+泥级长英质纹层2类纹层组合页岩。不同纹层源储特征差异显著,泥级长英质纹层和球粒状硅质纹层有机质含量高,发育层状结构藻、红藻果孢子等优质生烃母质,是主要的生油层;粉砂级长英质纹层发育石英/长石晶间孔、长石粒内溶蚀孔等微纳米孔隙,游离油占比高,为优势储集层。多种类型纹层叠置,通过控制页岩有机-无机相互作用、储集空间特征和烃类微运移过程,最终导致不同层段页岩油差异富集,其中,粉砂级+泥级长英质纹层为最佳源储配置,整体含油性好且分布广泛,构成泥生砂储的富集模式,是勘探开发的有利目标。

关键词: 准噶尔盆地, 陆相页岩油, 风城组, 纹层结构, 源储耦合, 甜点形成机理

Abstract:

Significant breakthroughs have been made in the exploration of continental shale oil in China. However, the strong heterogeneity and complex source-reservoir coupling in these shales have hindered the understanding of sweet spot formation mechanism. In this paper, taking the Permian Fengcheng formation in the Junggar Basin as an example, the characteristics of shale laminae and their controls on shale oil sweet spots were systematically investigated using multiple techniques such as large-area thin-section scanning, scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), confocal laser scanning microscopy (CLSM), and organic geochemical analysis. The results indicate that the lacustrine shales of the Fengcheng formation are well-laminated. The laminae can be classified into six types: silt-grade felsic lamina (SFL), argillaceous-grade felsic lamina (AFL), sparry dolomitic lamina (SDL), sparry calcite lamina (SCL), spherulitic siliceous lamina (SSL), and alkaline mineral lamina (AML). Two predominant laminated shale combinations are identified, i.e., SFL + AFL, and SCL/SDL + AFL. These lamina types exhibit significant variations in source-reservoir characteristics. AFL and SSL, characterized by high organic matter (OM) contents and the presence of high-quality hydrocarbon precursors such as laminated algae and rhodophyta spores, serve as the primary hydrocarbon-generating laminae. In contrast, SFL exhibits well-developed micropores and nanopores, including quartz/feldspar intercrystallline pores and feldspar intragranular dissolved pores, with a high proportion of free oil, rendering it favorable reservoir lamina. The superimposition of multiple lamina types governs organic-inorganic interactions, reservoir space characteristics, and hydrocarbon micro-migration processes, ultimately leading to differential enrichment of shale oil across various intervals. It is noted that the SFL + AFL combination represents the optimal source-reservoir configuration, demonstrating excellent overall oil content and forming an enrichment model characterized by oil generation in argillaceous lamina and accumulation in silty lamina. This combination is identified as a favorable target for shale oil exploration and development.

Key words: Junggar Basin, continental shale oil, Fengcheng formation, lamina structure, source-reservoir coupling, sweet spot formation mechanism

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