Abstract: A method is provided for placement of a gravel pack within perforations extending into a formation from a wellbore, the method comprising the steps of:a) injecting a pad fluid into the perforations, the pad fluid having a viscosity, at an ambient temperature of the perforations, of less than about 3 cp (measured at a shear rate of 100 sec.sup.-1), at a rate of at least 1/4 gpm per perforation for at least 5 minutes; andb) injecting a gravel slurry into the perforations at a rate of at least 1/4 gpm per perforation, the gravel slurry comprising a carrier fluid, between about one quarter and about 5 pounds of gravel pack solids per gallon of carrier fluid, and the carrier fluid comprising an amount of thickener effective to impart a viscosity to the carrier fluid of more than about 3 centipoise (measured at a shear rate of about 100 sec.sup.

Abstract: A method is provided to produce a polymer-thickened solution for injection into a wellbore, the method comprising the steps of:a) providing an aqueous polymer solution or suspension;b) dispersing the aqueous polymer solution or suspension into an aqueous stream not containing any of the polymer through nozzles wherein the nozzles have an opening of no larger than a circle of about 1/8-inch diameter;c) passing the aqueous stream containing the polymer solution or suspension through a static mixer having a residence time of at least about 0.5 seconds; andd) injecting the polymer-thickened solution into a wellbore. The polymer-thickened solution prepared according to the present invention may be used as a fracturing fluid, combined with gravel pack sand and used for gravel packing a wellbore, used as an acid treatment composition or used as a fluid loss composition.

Abstract: An improved gravel packing process is provided in which a gravel pack slurry is thickened with succinoglycan and the slurry further comprises an amount of breaker effective to result in 80 percent settlement of sand from the slurry after a time period larger than about one hour and shorter than about three hours.

Abstract: An improved gravel packing process is provided in which a gravel pack slurry is thickened with succinoglycan and the slurry further comprises an amount of breaker effective to result in 80 percent settlement of sand from the slurry after a time period larger than about one hour and shorter than about three hours.

Abstract: Polymers used to prevent fluid loss from boreholes may be eliminated after a predetermined time by including with the polymer composition halogen-substituted organic acids or their salt derivatives. These components hydrolyze, releasing hydrogen-halogen acids which break down the polymers within the wellbore or formation.

Abstract: An improved process for recovering oil by flowing a mixture of steam and steam foam surfactant into an oil-containing subterranean reservoir, the improvement provided by using surfactants enriched in olefin disulfonate. The surfactants may be used in either a steam drive or a steam soak process. Disulfonate-enriched steam foam surfactants and mixtures are also described.

Abstract: An improved process for recovering oil by flowing a mixture of steam and steam foam surfactant into an oil-containing subterranean reservoir, the improvement provided by using surfactants enriched in olefin disulfonate. The surfactants may be used in either a steam drive or a steam soak process. Disulfonate-enriched steam foam surfactants and mixtures are also described.

Abstract: In a continuous or cyclic steam foam drive, recovery of an acidic reservoir oil (1) is improved by injecting steam accompanied by (a) enough dissolved alkaline monovalent salt to ion-exchange multivalent cations from the reservoir rocks and precipitate those ions in compounds which are insoluble in an alkaline aqueous liquid as well as forming soaps of the reservoir oil acids and (b) surfactants for foaming the steam and increasing the salt tolerance of an aqueous surfactant system containing the soaps of the reservoir oil acids, and (2) is further improved by using trona or an equivalent mixture of alkali metal carbonates and bicarbonates as the alkaline monovalent salt.

Abstract: In a continuous or cyclic steam foam drive, recovery of an acidic reservoir oil is improved by injecting steam accompanied by (a) enough dissolved alkaline monovalent salt to ion-exchange multivalent cations from the reservoir rocks and precipitate those ions in compounds which are insoluble in an alkaline aqueous liquid as well as forming soaps of the reservoir oil acids and (b) surfactants for foaming the steam and increasing the salt tolerance of an aqueous surfactant system containing the soaps of the reservoir oil acids.

Abstract: Oil is recovered from a subterranean oil reservoir by injecting foam-forming components through an injection well while preventing fluid outflow from an adjacent production well, so that the pressure is increased in the zone between the wells, then permitting fluid outflow from the production well while continuing the injection, until the rate of the outflow is significantly reduced, and repeating the injecting and outflowing steps until the rate of oil production is significantly reduced.

Abstract: In a process in which steam and steam-foaming surfactant are injected into a subterranean reservoir having significant cation-exchange capacity, the rate of transport of the steam-foaming surfactant is increased by a prior injection of an aqueous liquid solution of surfactant and monovalent cation salt.