组成砂砾岩骨架的颗粒通常存在多个粒径级配、分选差、非均质性强，导致其孔隙结构特征、岩电关系复杂，难以建立有效的含水饱和度测井计算方法。尽管砂砾岩分选性较差，但其常具有明显的分形特征。将多孔介质分形理论与导电效率理论相结合，推导砂砾岩分形导电效率模型，并在此基础上建立基于分形导电效率的含水饱和度计算方法。实井应用结果可见，在基于核磁共振（nuclear magnetic resonance, NMR）测井获取砂砾岩地层分形特征的基础上，分形导电效率模型能显著提升砂砾岩地层测井含水饱和度计算的准确性。结果表明：分形参数因具有统计自相似性和标度不变性，能够有效地表征砂砾岩的孔隙结构特征，在不进行孔隙结构类型测井划分的条件下，实现砂砾岩含水饱和度准确计算。从而克服了强非均质性地层，测井孔隙结构类型识别困难，导致孔隙结构类型划分错误、影响计算准确性的问题。所建分形导电模型不仅适用于砂砾岩地层，也可作为其他分选差、非均质性强地层含水饱和度测井计算的参考。

The grains composing the skeleton of conglomerate typically exhibit multiple particle size gradations, poor sorting, and strong heterogeneity, leading to complex pore structure characteristics and petrophysical relationships, which make it difficult to establish an effective logging method for water saturation calculation. Despite its poor sorting, conglomerate often displays distinct fractal characteristics. The fractal theory of porous media was combined with conductivity efficiency theory to derive a fractal conductivity efficiency model for conglomerate. Based on this model, a water saturation calculation method was established using fractal conductivity efficiency. Practical well application results demonstrate that, based on obtaining the fractal characteristics of conglomerate formations through nuclear magnetic resonance(NMR) logging, the fractal conductivity efficiency model can significantly improve the accuracy of water saturation calculations in conglomerate formations. The results indicate that fractal parameters, due to their statistical self-similarity and scale invariance, can effectively characterize the pore structure features of conglomerate. This enables accurate calculation of water saturation in conglomerate without the need for logging classification of pore structure types. Thus, it overcomes the challenges posed by strongly heterogeneous formations where logging identification of pore structure types is difficult, which can lead to misclassification of pore structure types and affect calculation accuracy. The established fractal conductivity model is not only applicable to conglomerate formations but can also serve as a reference for water saturation logging calculations in other formations with poor sorting and strong heterogeneity.