Shale pore connectivity is of great significance for the enrichment and development of shale oil; however, quantitative evaluations are difficult owing to the tightness, heterogeneity, and complex wettability of shale. This paper presents a spontaneous imbibition technique combined with nuclear magnetic resonance (SI-NMR) that was established to probe the shale pore connectivity—especially the connectivity of pores with different sizes and wettabilities—of a set of shales with low–medium maturity from the Shahejie Formation of the Jiyang depression. The research results indicate that the micropore connectivity was the greatest, followed by that of mesopores and macropores (or bedding fracture or microfractures); additionally, the connectivity of water-wet pores is better than that of oil-wet pores. The oil imbibition slope reflecting pore connectivity has a negative correlation with the PI (production index), a positive correlation with T_max (reflecting organic matter maturity) and calcite content, and no significant correlation with the contents of TOC (total organic carbon) or other minerals. This research also revealed that the length and imbibition area of shale have little effect on the imbibition slope, while anisotropy in the imbibition direction and preferential imbibition in small pores substantially affect the slope. This study provides a method for evaluating the connectivity of different pore scales in shale, which is expected to help understand the flow mechanism and production characteristics of shale oil. The results are thus of great significance to improve shale oil evaluation and to find favorable development areas for shale oil.

页岩孔隙连通性对页岩油的富集和开发具有重要意义；然而，由于页岩的致密性、非均质性和复杂的润湿性，定量评价很困难。本文提出了一种与核磁共振 (SI-NMR) 相结合的自吸技术，该技术用于探测一组中低成熟度页岩的页岩孔隙连通性，尤其是不同大小和润湿性的孔隙的连通性。济阳坳陷沙河街组. 研究结果表明，微孔连通性最大，其次是介孔和大孔（或层理裂缝或微裂缝）；此外，水湿孔隙的连通性优于油湿孔隙。_max（反映有机质成熟度）和方解石含量，与TOC（总有机碳）或其他矿物质含量无显着相关性。研究还表明，页岩长度和渗吸面积对渗吸坡度影响不大，而渗吸方向各向异性和小孔隙优先渗吸对坡度影响较大。该研究为评估页岩中不同孔隙尺度的连通性提供了一种方法，有望有助于了解页岩油的流动机制和生产特征。研究结果对提高页岩油评价水平，寻找页岩油有利开发区具有重要意义。