Fracture Stimulation Utilizing a Viscoelastic-Surfactant-Based System in the Morrow Sands in Southeast New Mexico

摘要

This paper discusses the selection criteria, design methodology, and analysis of hydraulic fracturing treatments pumped using a solids-free, liquid CO2 foam-based visco- elastic surfactant (VES) fluid system in Morrow Sand reservoirs located in Southeast New Mexico (SENM). The wells discussed in the paper were completed in various Morrow Sand intervals around 10,500 ft with an average Bottom Hole Static Temperature (BHST) of 190oF. Wellbore completion constraints combined with reservoir parameters inclusive of low-pressured water sensitive formations, high rock Youngs’ Modulus and unpredictable occurrence of water-bearing zones, lead to the selection of foamed VES fluids. This technology was successfully applied in the Morrow Sands in Eddy County of SENM. Fracture geometry analysis using surface treating pressures, radio- active tracers and production data, showed height growth containment and longer effective fracture half-lengths. Results also indicated succes sful stimulation past the cement squeezed intervals and temporary liner tie-backs run in to overcome lower pressure constraints. Finally, lower friction pressures helped in designing economical fracture stimulations for mature wellbores thereby generating an opportunity to recover otherwise bypassed hydrocarbon reserves.