目前研究认为海陆过渡相页岩整体孔隙体积较小，有机质孔欠发育，储集性较低。然而多尺度镜下观察结果表明海陆过渡相页岩中发育大尺度有机质孔，具备一定的生烃潜力，但对这类储集空间的研究程度较低。此外，受到孔隙结构表征实验设备精度的限制，中-大孔定量表征的准确性较低，从而低估了海陆过渡相页岩的产气能力。为此，以鄂尔多斯盆地东缘临兴地区山西-太原组页岩为研究对象，通过明确不同尺度同步辐射纳米扫描计算机断层（computed tomography, CT）图像三维重构数据处理方法，定量表征页岩样品的大孔孔隙体积和形态特征，提高大孔表征的准确性和客观性。结合扫描电镜、高压压汞、氮气吸附和二氧化碳吸附实验定性和定量表征海陆过渡相页岩的多尺度孔缝发育特征，并通过总有机碳和X射线全岩衍射实验分析中-大孔孔缝大小、结构影响因素。结果表明，山西-太原组时期页岩孔隙体积贡献主要为中孔和大孔。其中，太原组页岩的孔隙体积小于山西组页岩，其孔隙体积均值为5.9 × 10^-3 cm³/g，其中中孔占比47%，大孔占比45%，黏土矿物含量相对较高，有机质孔相对欠发育，伴随黏土矿物之间转化，形成扁平状微米级褶皱缝。山西组页岩的总孔隙体积为12.5 ×10^-3 cm³/g，其中中孔占比52%，有机质中-大孔发育，受到石英含量相对较高，抗压实性强的影响，有机质孔、球状和形状较为规则的粒间孔得以有效保存，具有较好储集性，为指导海陆过渡相页岩勘探开发提供有利依据。

Research shows that transitional shales has a small pore volume and poorly developed organic matter pores, leading to lower reservoir quality. However, multi-scale observations reveal organic pores with large pore volume, indicating significant hydrocarbon potential. Further investigation is needed as current studies are insufficient. In addition, due to limitations in the precision of pore structure characterization equipment, the accuracy of quantifying mesopores and macropores are low, leading to an underestimation of gas production in marine-continental transitional shale. Therefore, focusing on the shale of Shanxi-Taiyuan Formation from the Linxing area of the eastern margin of Ordos Basin, by developing method for the higher resolution synchrotron radiation nano-CT at various scales, the large-pore volume and morphology of the shale samples were quantitatively characterized, thereby improving the accuracy and objectivity of large-pore characterization. Besides, scanning electron microscope (SEM), high pressure mercury experiment, nitrogen adsorption and carbon dioxide adsorption experiments were used to characterize the multi-scale pores in transitional shale. Combined with total organic carbon and X-ray diffraction experiments, the pore structure influencing factors were also analyzed. The results show that during the Shanxi-Taiyuan period, shale pore volume is primarily contributed by mesopores (47%) and macropores (45%). The Taiyuan Formation shale has a lower average pore volume of 5.9 × 10^-3 cm³/g. It also features relatively higher clay mineral content and underdeveloped organic matter pores, accompanied by the transformation between clay minerals to form flattened micro-fracture. The total pore volume of the Shanxi Formation shale is 12.5 × 10^-3 cm³/g, with mesopores accounting for 52%. Medium to large organic matter pores are well-developed. Due to the relatively high quartz content and strong compaction resistance, organic matter pores, spherical pores, and intergranular pores with relatively regular shapes are effectively preserved, resulting in favorable reservoir properties. This provides a valuable basis for guiding the exploration and development of transitional shale.