苏北盆地高邮凹陷阜宁组二段（以下简称阜二段）页岩油勘探获得突破，是未来增储上产的现实目标。裂缝作为储集空间和运移通道，在页岩油勘探开发中发挥着重要作用。以X1井为研究对象，根据成像测井、岩心和微观薄片观察结果，分析了高邮凹陷阜二段页岩油储层不同尺度裂缝发育特征；结合裂缝参数统计和裂缝充填物稳定碳氧同位素分析，确定了裂缝形成期次，讨论了裂缝动态演化过程及裂缝对页岩油气富集的影响。结果表明：构造裂缝总体较为发育，主要为脆性剪切裂缝和张剪性裂缝，剪切裂缝长度长，横向连通性好；非构造裂缝主要为层理缝和顺层方解石脉，在部分亚段异常发育。不同类型的天然裂缝后期均遭受了一定程度的改造，未被完全充填的裂缝、裂缝充填物溶蚀形成的孔洞，以及超压层理缝和微裂隙，均是页岩油有利的储集空间。研究结果为高邮凹陷深层页岩油选区、选段提供了新的思路和理论依据。

Recent exploration within the second member of Funing Formation（hereinafter referred to as Fu-2 member）in Gaoyou Sag of Subei Basin has marked a significant advancement in the understanding of shale oil potential, highlighting its role in enhancing future reserves and production. This study focuses on Well-X1, utilizing a comprehensive suite of analytical techniques, including imaging logging, core examinations, and micro thin section analysis, to investigate the fracture characteristics across different scales. Additionally, statistical analysis of fracture parameters and isotopic studies of stable carbon and oxygen in fracture fillings provide insights into the formation stages of the fracture. The research delves into the dynamic evolution of fractures and their influence on the accumulation of shale oil and gas. Key findings indicate that structural fractures, predominantly brittle shear and tensile shear fractures, are prevalent and characterized by substantial length and excellent transverse connectivity. Non-structural fractures, including bedding fractures and calcite veins, exhibit some areas of abnormal development. These natural fractures have undergone modifications during later stages, with incompletely filled fractures, pore spaces from dissolved fracture fillers, overpressure bedding fractures, and micro fractures identified as particularly favorable reservoir spaces for shale oil. The results of this study not only shed light on the complex fracture dynamics within the shale but also provide a robust theoretical foundation for evaluating deep shale oil prospects in Gaoyou Sag.