摘要: 摘 要 源储压差不仅作为非常规油气的成藏动力，还是研究页岩油甜点成因不可缺少的关键内容，加之陆相页岩广泛发育纹层结构，其发育程度造成储集岩成藏动力的差异影响着页岩油气的聚集，但目前对页岩油成藏动力方面的探究相对较少。以准噶尔盆地吉木萨尔凹陷二叠系芦草沟组甜点段为研究对象，从成藏动力角度揭示纹层结构发育程度与页岩油气聚集的内在关联。通过对烃源岩评价、岩相学类型划分及孔隙表征等手段，获取研究区甜点段烃源岩、不同类型储集岩及源储组合类型特征。利用等效深度法与流体包裹体模拟分别恢复出成藏期烃源岩与储集岩的压力差值，得到不同类型储集岩的成藏动力。结果表明：研究区以源储互层型组合为主，优质烃源岩生烃作用使源储间形成较强的源储压差，推动油气不断运移至相邻的储集空间中；储集岩内部广泛发育粉砂质与泥质纹层互层，构成了源储大面积频繁接触，其发育程度造成不同类型储集岩成藏动力存在差异，纹层状储集岩纹层结构发育，缩短了油气运移的距离，使其具备更强的成藏动力和含油性。下甜点段纹层状储集岩发育段是研究层段页岩甜点油气运聚的有利区。
The Influence of Reservoir Forming Dynamics on Shale Oil and Gas Accumulation: A Case Study of Lucaogou Formation in Jimusar Sag, Junggar Basin
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Abstract: Abstract: The pressure differences between source and reservoir rocks is not only the driving force for unconventional oil and gas accumulation, but also an indispensable key content in the study of the genesis of shale oil sweet spots. In addition, laminar structures are widely developed in continental shale, and the degree of development results in differences in the accumulation dynamics of reservoir rocks, which affect the accumulation of shale oil and gas. However, there are relatively few studies on the accumulation dynamics of shale oil. The sweet spot section of the Permian Lucaogou Formation in the Jimusar Sag was taken as the research object, and the intrinsic relationship between the development degree of laminar structure and shale oil and gas accumulation was revealed from the perspective of accumulation dynamics. Through evaluation of source rocks, classification of petrographic types and characterization of pores, etc. The characteristics of source rocks, different types of reservoir rocks, and source-reservoir assemblages in the study area were obtained. Using the equivalent depth method and fluid inclusion simulation, the pressure difference between source rocks and reservoir rocks during the accumulation period was recovered, and the accumulation dynamics of different types of reservoir rocks were obtained. The results show that the study area is dominated by source-reservoir interbedded combinations, and the hydrocarbon generation of high-quality source rocks creates a strong source-reservoir pressure difference between source and reservoir, which promotes the continuous migration of oil and gas to adjacent reservoir spaces; Interbedded silty and argillaceous laminae are widely developed in the reservoir rocks, which constitute a large area of frequent contact between source and reservoir. The degree of development results in differences in the accumulation dynamics of different types of reservoir rocks, and the laminar reservoir has developed laminar structure and the migration distance of oil and gas is shortened, so that it has stronger accumulation power and oil-bearing property. The development of laminar reservoir rocks in the lower sweet spot is a favorable area for studying oil and gas migration and accumulation in the shale sweet spot.