针对海陆过渡相碳质与硅质页岩岩石力学性质方面的差异，利用有限元ABAQUS数值模拟软件建立水力压裂模型，分析岩性差异与压裂参数对水力裂缝扩展特征的影响，并引入压裂指数优选最佳碳质和硅质页岩水力压裂簇数及簇间距。结果表明：碳质页岩水力缝长相对于硅质页岩较短，而缝宽相对于硅质页岩较宽，硅质页岩脆性强，抵抗变形能力也强，形成长窄型具有较大波及范围的水力裂缝；碳质页岩水力裂缝起裂压力小，且扩展压力高于起裂压力，而硅质页岩水力裂缝的起裂压力较大，但起裂后会出现明显的压降，证明硅质页岩更易于压裂，所需的压裂液体积也较少；通过压裂指数优选碳质页岩的最佳簇数及簇间距为12簇和11 m簇间距，而硅质页岩为13簇和9 m簇间距，建议进行现场水力压裂碳质页岩时易采用“少簇数大簇距”，硅质页岩采用“多簇数小簇距”压裂；压裂指数较大的压裂参数下，其日产气量也较大，最佳压裂参数的日产气量与现场相同压裂参数的日产气量趋势符合度在97%。

Aiming at the differences in mechanical properties of carbonaceous and siliceous shale rocks in transitional facies, a hydraulic fracturing model was established using the finite element ABAQUS numerical simulation software. The influence of lithological differences and fracturing parameters on the characteristics of hydraulic fracture propagation was analyzed, and the optimal number and spacing of carbonaceous and siliceous shale hydraulic fracturing clusters were optimized by introducing fracturing index. The results show that: the hydraulic fracture length of carbonaceous shale is shorter than that of siliceous shale, while the fracture width is wider than that of siliceous shale. The siliceous shale has strong brittleness and strong resistance to deformation, forming long and narrow hydraulic fractures with a large sweeping range; the initiation pressure of hydraulic fractures in carbonaceous shale is small, and the propagation pressure is higher than the initiation pressure. On the other hand, the hydraulic fracture initiation pressure of siliceous shale is higher, but there will be a significant pressure drop after the initiation of the fracture, which proves that siliceous shale is easier to fracturing and requires less fracturing fluid volume; the optimal number of clusters and the cluster spacing of carbonaceous shale are optimized by fracturing index as 12 clusters and 11 m cluster spacing, and the optimal inter-cluster and cluster spacing of siliceous shale are 13 clusters and 9 m cluster spacing. It is suggested that “small number of clusters with large cluster spacing” is easy to be used for on-site hydraulic fracturing of carbonaceous shale, and “multiple clusters with small cluster spacing” for siliceous shale fracturing; under the fracturing parameters with a larger fracturing index, the daily gas production is also larger, and the daily gas production of the optimal fracturing parameters coincides with the daily gas production trend of the same fracturing parameters on site at 97%.