First-Of-Its-Kind Stimulation of Stacked Reservoirs: Overcoming Pressure Constraints with Multi Modal Particulate Diversion, High Viscosity Friction Reducer and Channel Fracturing Technique

Abstract Candidate well is an inclined development well targeting the Ordovician reservoirs in the Hamra field, specifically the Ouargla Sandstone and the underlying Hamra Quartzite. The Ouargla sandstone interval (upper) had previously been stimulated with limited success, posing a significant challenge for subsequent treatments due to its behavior as a thief zone. Additionally, elevated near-wellbore friction and surface pressure constraints limited the operational flexibility of the treatment design, restricting the achievable injection rates and complicating the placement of treatment fluids across both target intervals. A first-time, reservoir-specific stimulation strategy was implemented to address these challenges within this multi-layered system. A limited-rate DataFRAC was conducted to prevent premature fracture propagation into the quartzite Hamra and ensure effective pill placement toward the Ouargla sandstone by maintaining controlled net pressure growth. The use of Multi-Modal Particulate Diversion technology enabled redirection away from previously stimulated and pressure-depleted zones, thereby improving fracture coverage. High-viscosity friction reducers (HVFR) were deployed to manage net pressure buildup and enhance proppant transport, while S100 mesh slugs were used to mitigate near-wellbore friction and optimize fracture initiation characteristics. The treatment resulted in a confirmed diversion from the Ouargla Sandstone to the Hamra Quartzite. A notable pressure drop—rising from an initial 500 psi to a 2000 psi operational margin—was observed post-S100 slug placement, confirming reduced near-wellbore friction and improved wellbore conductivity. The entire designed proppant volume was successfully placed using the channeling technique, ensuring adequate proppant distribution across the target interval. This case demonstrates the technical feasibility of stimulating stacked reservoirs with pre-existing fracture networks under severe pressure constraints through an optimized, multi-technology workflow. It further highlights the value of integrating diversion, friction management, and controlled-rate diagnostics to refine stimulation efficiency in complex, low-tolerance operating environments.