Previous studies1-4 described the theory and application ofCO2 miscible hydrocarbon fracturing fluids for gas wellstimulation. These fluids are ideally suited to gas reservoirssusceptible to phase trapping resulting from high capillarypressures when water-based fluids are used. Gas reservoirsparticularly prone to phase trapping are those with in situpermeability less than 0.1 md, those with initial watersaturations less than what would be expected from normalcapillary equilibrium (subnormally water saturated), and thosethat are under pressured.Such reservoirs represent a growing proportion of themarket. This, combined with increased gas prices creates astrong need for an optimized gas well fracturing fluid system.Hydrocarbon-based fracturing fluids present an idealsolution to phase trapping concerns associated with waterbasedfluids provided the hydrocarbon fluid can be effectivelyand quickly removed from the formation after the fracturingtreatment.
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