Optimization of Perforation Parameters for Shale Gas Horizontal Wells in Weiyuan Block, Sichuan Basin

Horizontal well multi-cluster fracturing has been recognized as an effective technology to extract shale gas resources. This paper proposed a full 3D model of multi-cluster fractures propagation with perforation tunnels by using 3D lattice method. The oriented perforation and spiral perforation modes were compared to understand their distinct of multiple fractures initiation and propagation. The particular conditions of Weiyuan shale gas block and the strike-slip fault were taken account. The uniformity of fractures propagation and their impacting factors were analyzed. Results demonstrated that the oriented perforation promotes plannar fractures with less twist but the number of perforation tunnels is relatively small with big perforation friction comparing to the spiral perforation. The case study takes the optimized combination of engineering parameters to achieve the uniform propagation with the pumping rate for single cluster of above 2m³/min, perforation density of 6 per foot, and the cluster spacing of over 10m. This work provides a modeling workflow to consider the perforation tunnels and the optimized parameters for uniform hydraulic fracturing.