Enhancing uniformity of multi-fracture propagation by temporary plugging and diversion fracturing in a horizontal well with multi-cluster perforations

Abstract

Multi-stage and multi-cluster fracturing (MMF) is a crucial technology in unconventional oil and gas development, aiming to enhance production by creating extensive fracture networks. However, achieving uniform expansion of multi-cluster hydraulic fractures (HFs) in MMF remains a significant challenge. Field practice has shown that the use of temporary plugging and diversion fracturing (TPDF) can promote the balanced expansion of multi-cluster HFs. This study conducted TPDF experiments using a true triaxial fracturing simulation system setting a horizontal well completion with multi-cluster jetting perforations to investigate the equilibrium initiation and extension of multi-cluster fractures. The influence of key parameters, including cluster spacing, fracturing fluid viscosity, differential stress, and fracturing fluid injection rate, on fracture initiation and propagation was systematically examined. The results indicate that while close-spaced multi-cluster fracturing significantly increases the number of HFs, it also leads to uneven extension of HFs in their propagation. In contrast, TPDF demonstrates effectiveness in mitigating uneven HF extension, increasing the number of HFs, and creating a larger stimulated reservoir volume, ultimately leading to improved oil and gas well productivity. Moreover, under conditions of high differential stress, the differential stress within the formation exerts a stronger guiding effect in HFs, which are more closely aligned with the minimum principal stress. Low-viscosity fluids facilitate rapid and extensive fracture propagation within the rock formation. High-volume fluid injection, on the other hand, more comprehensively fills the formation. Therefore, employing low-viscosity and high-volume fracturing is advantageous for the initiation and extension of multi-cluster HFs.