Abstract: An aqueous viscoelastic fluid for enhancing the productivity of a subterranean formation contains, in addition to an anionic surfactant and a cationic surfactant, hydroxyethyl cellulose (HEC). The fluid may be pumped neat into the formation, foamed with nitrogen to qualities exceeding 90% or emulsified with liquid carbon dioxide to emulsion quality approaching 90%.

Abstract: Gelled emulsions contain (i.) an external phase of an aqueous water-soluble solvent solution, polymeric viscosifying agent and, optionally, an oxidative and/or acidic breaker; and (ii.) an internal phase of a dispersed organic fluid. The aqueous water-soluble solvent solution constitutes between from about 15 to about 50 volume percent of the gelled emulsion and the dispersed organic fluid is presented in the gelled emulsion in amounts ranging from about 50 to about 85 volume percent. The gelled emulsions are useful in a variety of applications including, but not limited to, oil field, pipeline and processing facility applications.

Abstract: A method of using an organic peroxide containing composition as a gel breaker and a method of transporting the composition is disclosed, wherein the composition has a freeze point less than or equal to ?10° C. and a diluent which contains water and an organic solvent selected from ethylene glycol, methanol, ethanol and 1-propanol. During shipment, the amount of available oxygen in the composition is less than or equal to 1 weight percent.