Optimization of Volumetric Fracturing Stages and Clusters in Continental Shale Oil Reservoirs Based on Geology-Engineering Integration

The exploration and development of shale oil offers significant potential as an alternative to address oil and gas supply. The complex geological conditions characterized by inter-lithology and strong heterogeneity pose substantial challenges in fracturing reconstruction. This paper established an integrated geoengineering model of Gulong shale in the Songliao Basin using multi-source data to accurately characterize the vertical and lateral heterogeneity of the reservoir. Based on the reconstruction economy, the compressibility evaluation of different reservoirs showed that the advantage of reconstruction was highest in the Q9 reservoir and lowest in the Q3 reservoir. Analysis of the fluctuation in the reservoir compressibility and lithology characteristics revealed limited fracture reconstruction volume in highly plastic reservoirs with elevated mudstone concentrations, which affected reconstruction efficacy. The number of clusters could be increased while the spacing between the clusters could be reduced in the lithologically brittle region. In areas characterized by strong lithology and plasticity, the number of clusters was appropriately decreased while the inter-cluster spacing increased. The research results allow local adjustments according to the logging curve, inform differentiated decisions on fracturing reconstruction, and support the efficient fracturing reconstruction of the Gulong shale oil reservoir.