Abstract: A method and composition for controlling the profile of a formation where temperatures higher than 400.degree. F. are encountered. An aqueous solution of an organoammonium silicate, alkali metal or ammonium silicate is injected into a zone of higher permeability in a formation. Subsequently, a spacer volume of a water-immiscible organic solvent is directed into said zone. Afterwards, a water-miscible organic solvent containing an alkylpolysilicate and an inorganic salt or a chelated calcium compound are injected into the higher permeability zone. A silicate cement is formed in-situ thereby substantially closing the higher permeability zone to fluid flow. Thereafter, a steam-flooding, water-flooding, carbon dioxide-flooding, or fire-flooding EOR operation is commenced in a lower permeability zone.

Abstract: A method for forming a gravel pack in a washed-out interval is provided where a borehole penetrates an unconsolidated or loosely consolidated oil or gas reservoir which is likely to introduce substantial amounts of sand into the borehole. After perforating the boreholes's casing at a washed-out interval of the formation, sand is introduced into the interval. Afterwards, an aqueous silicate slug is injected into said interval. Next, a spacer volume of a water-immiscible hydrocarbonaceous liquid is introduced into the interval. Thereafter, a water-miscible organic solvent slug, containing an alkylpolysilicate and an inorganic or organic salt or a chelated calcium mixture, is injected into the interval. A permeability retaining silicate cement is formed in the interval thereby making a gravel pack.

Abstract: A method for gravel packing perforations in a wellbore where an acid is directed into the perforations so as to dissolve formation fines in channels contained in said perforations. The acid is of a strength sufficient to dissolve said fines. After the fines are dissolved, a three slug sand consolidating agent is introduced into the perforations before the channels can be filled with formation fines. The consolidating agent remains in the perforations for a time sufficient to form a silicate cement in situ which cement has permeability retentive characteristics. The cement forms pores of a size sufficient to exclude formation fines from the wellbore. Thereafter, the wellbore is packed with gravel to remove any escaping fines from hydrocarbonaceous fluids produced to the surface.

Abstract: A method and composition for controlling the profile of a formation where temperatures higher than 200.degree. F. are encountered. An aqueous solution of an organoammonium silicate, alkali metal or ammonium silicate is injected into a zone of higher permeability in a formation. Subsequently, a spacer volume of a water-immiscible organic solvent is directed into said zone. Afterwards, a water-miscible organic solvent containing an alkylpolysilicate is injected into the higher permeability zone. A silica cement is formed in-situ thereby substantially closing the higher permeability zone to fluid flow. Thereafter, a steam-flooding, water-flooding, carbon dioxide-flooding, or fire-flooding EOR operation is commenced in a lower permeability zone.

Abstract: A method for forming a consolidated gravel pack in a washed-out interval is provided where a borehole penetrates an unconsolidated or loosely consolidated oil or gas reservoir which is likely to introduce substantial amounts of sand into the borehole. After perforating the borehole's casing at a washed-out interval of the formation, sand is introduced into the interval. Afterwards, an aqueous hydroxide solution is injected into said interval. Next, a spacer volume of a water-immiscible hydrocarbonaceous liquid slug is injected into the interval. Thereafter, a water-miscible organic solvent slug containing alkylpolysilicate is injected into the interval. A permeability retentive silica cement is formed in the interval thereby making a consolidated gravel pack. Injection of the aqueous hydroxide and alkylpolysilicate slugs is continued until silica cement has been deposited to an extent sufficient to exclude formation fines and sand.

Abstract: A method for forming a gravel pack in a washed-out interval is provided where a borehole penetrates an unconsolidated or loosely consolidated oil or gas reservoir which is likely to introduce substantial amounts of sand into the borehole. After perforating the borehole's casing at a washed-out interval of the formation, sand is introduced into the interval. Afterwards, an aqueous silicate solution is injected into said interval. Next, a spacer volume of a water-immiscible hydrocarbonaceous liquid is introduced into the interval. Thereafter, a water-miscible organic solvent containing an alkylpolysilicate is injected into the interval. A permeability retaining silica cement is formed in the interval thereby making a gravel pack. Injection of the aqueous silicate and organic solvent containing an alkylpolysilicate is continued until the interval has been consolidated by the silica cement to an extent sufficient to exclude sand and formation fines.

Abstract: A sand consolidating method is provided for use in a borehole within an unconsolidated or loosely consolidated oil or gas reservoir which is likely to introduce substantial amounts of sand into the borehole and cause caving. After perforating the borehole's casing at an interval of the formation where sand will be produced, an aqueous silicate solution is injected into said interval. Next, a spacer volume of a water-immiscible hydrocarbonaceous liquid is introduced into the interval. Thereafter, a water-miscible organic solvent containing an alkylpolysilicate and inorganic salt or chelated calcium is injected into the interval. A permeability retentive silicate cement is formed in the interval. Injection of the aqueous silicate and organic solvent is continued until the interval has been consolidated by the silicate cement to an extent sufficient to prevent sand migration and thereby prevent caving.

Abstract: A method for controlling the profile of a formation where temperatures higher than 200.degree. F. are encountered. Initially, an aqueous solution of an alkali metal hydroxide, ammonium hydroxide or organoammonium hydroxide is injected into a zone of greater permeability in a formation. Thereafter, a spacer volume of a water miscible organic solvent is injected into said zone. Afterwards, a water-miscible organic solvent containing an alkylpolysilicate is injected into the greater permeability zone. A silica cement is formed in-situ thereby substantially closing off the higher permeability zone to fluid flow. Thereafter, a steam-flooding, water-flooding, carbon dioxide stimulation or fire-flooding EOR operation is commenced in a lower permeability zone.

Abstract: A sand consolidation method is provided for use in a borehole having an unconsolidated or loosely consolidated oil or gas reservoir which is likely to introduce substantial amounts of sand into the borehole and cause caving. After perforating the borehole's casing at an interval of the formation where sand will be produced, an aqueous silicate solution is injected into said interval. Next, a spacer volume of a water-immiscible hydrocarbonaceous liquid is introduced into the interval. Thereafter, a water-miscible organic solvent containing an alkylpolysilicate is injected into the interval. A permeability retaining silica cement is formed in the interval. Injection of the aqueous silicate and organic solvent containing an alkylpolysilicate is continued until the interval has been consolidated by the silica cement to an extent sufficient to prevent sand migration and thereby prevent caving.

Abstract: A gel-forming composition capable of plugging highly permeable zones in a subterranean formation. The composition comprises water, a viscosifying amount of a water-dispersible polyvinyl amine copolymer and a crosslinking agent which is a mixture of an aldehyde and a phenolic component in an amount effective to cause gelation of the aqueous solution of the copolymer. The resultant gel is exceptionally thermally stable and, therefore, can be used as an effective profile control agent in all enhanced oil recovery operations, including steam flooding.

Abstract: High molecular weight polyvinyl alcohols can be modified with amino compounds such as acrylamide in a one-step low temperature reaction to produce products having higher viscosity than those prepared in costly two-step high temperature modification reactions.

Abstract: A method for controlling the profile of a formation where temperatures higher than 400 degress F. are encountered. An aqueous solution of potassium silicate is injected into a zone of greater permeability in a formation. Afterwards, an alcoholic solution of hydrated calcium chloride is injected into the greater permeability zone. Calcium silicate is formed in-situ thereby substantially reducing the permeability of the higher permeability zone. Thereafter, a steam-flooding or fire-flooding operation is commenced in a lower permeability zone.

Abstract: A method for forming a gravel pack in a washed-out interval is provided where a borehole penetrates an unconsolidated or loosely consolidated oil or gas reservoir which is likely to introduce substantial amounts of sand into the borehole. After perforating the borehole's casing at a washed-out interval of the formation, sand is introduced into the interval. Afterwards, an aqueous solution of potassium silicate is injected into said interval. Thereafter, an alcoholic solution of hydrated calcium chloride is injected into the interval. A permeability retaining calcium silicate cement is formed in the interval thereby making a gravel pack. Injection of the potassium silicate and hydrated calcium chloride solutions is continued until the porosity of the interval has been reduced by the calcium silicate cement to an extent sufficient to exclude formation fines and sand.

Abstract: A gel-forming composition capable of plugging highly permeable zones in a subterranean formation. The composition comprises water, a water-dispersible polyvinyl alcohol copolymer and a crosslinking agent which is a mixture of an aldehyde and a phenolic component in an amount effective to cause gelation of the aqueous solution of the copolymer. The resultant gel is exceptionally thermally stable and, therefore, can be used as an effective profile control agent in all enhanced oil recovery operations, including steam flooding. Also provided is a process for recovering oil from a subterranean oil-bearing formation.

Abstract: A sand consolidation method is provided for use in a borehole having an unconsolidated or loosely consolidated oil or gas reservoir which is likely to introduce substantial amounts of sand into the borehole and cause caving. After perforating the borehole's casing at an interval of the formation where sand will be produced, an aqueous solution of potassium silicate is injected into said interval. Thereafter, an alcoholic solution of hydrated calcium chloride is injected into the interval. A permeability retaining calcium silicate cement is formed in the interval. Injection of the potassium silicate and hydrated calcium chloride solutions is continued until the interval has been consolidated by the calcium silicate cement to an extent sufficient to prevent sand migration and thereby prevent caving.

Abstract: A process for use with a polymer which is crosslinkable by reaction with an amino resin, which comprises the steps of determining a period of time within which full gelation of the polymer is to be achieved; preparing a gel-forming aqueous-based mixture comprising the polymer, a rapid amino resin crosslinking agent and a delayed amino resin crosslinking agent, the gel-forming aqueous-based mixture capable of complete gelation within the period of time so determined; partially gelling the aqueous-based mixture by reacting the polymer with the rapid amino resin crosslinking agent which is effective to complete the partial gelation by crosslinking the polymer within four hours; and fully gelling the aqueous-based mixture by reacting the polymer with the delayed amino resin crosslinking agent which is effective to complete the full gelation by crosslinking the polymer within the period of time so determined. A method of enhancing the recovery of oil from a subterranean oil-bearing formation is also provided.

Abstract: A composition for closing pores in a formation following a steam-flooding enhanced oil recovery process. The composition comprises an aqueous temperature activated gellable mixture. This mixture is comprised of water, water dispersible polymers, phenolic compounds, and aldehyde producing compounds. Polymers which can be utilized herein include polyvinyl alcohol, polyacrylamide and poly(acrylamide-co-acrylamido-2-methylpropane sulfonate). Phenol is the phenolic compound of choice. At a formation temperature greater than 300.degree. F., trioxane, the preferred aldehyde producing compound decomposes to yield formaldehyde which reacts with phenol to form phenolic resin in situ. The resin gels the polymer and forms a solid gel in a heated zone of the formation.

Abstract: A method for minimizing well recompletions in a multiple zone hydrocarbonaceous fluid containing formation. A steam flooding enhanced oil recovery (EOR) is conducted in the upper zone of said formation via fluidly communicating injector and producer wells which penetrate the upper and lower zones. The wells are unperforated and do not communicate with each other in the lower zone. Thereafter, a temperature activated gellable composition is injected into the upper zone where it forms a solid gel. Afterwards, both wells are perforated so as to fluidly communicate with each other in the lower productive interval. Subsequently, a steam-flooding EOR operation is conducted in the lower level and hydrocarbonaceous fluids are removed therefrom. Polymers utilized in the gellable composition include polyvinyl alcohol and polyacrylamide cross-linked with phenol and an aldehyde producing compound sufficient to form a phenolic resin in situ.

Abstract: A composition of matter wherein amino resins such as melamine formaldehyde ("MF") resins co-gel and crosslink with polymers useful for profile control where said polymers have amine, amide, hydroxyl and thiol functionalities. Resulting gels are useful as permeability control agents for high temperature reservoirs during a water-flooding operation.

Abstract: The permeability of a subterranean oil-bearing formation is controlled by the injection of an aqueous solution of a cross-linked block copolymer containing polar and non-polar segments, with the polar segments generally making up as least 50 percent, usually 60 to 99 percent, of the copolymer. The polar segments are derived from an alkylene oxide and the non-polar segments from styrene or an alkyl styrene either by itself or with a diene. The copolymers are cross-linked with an amino resin or a combination of a phenolic and a water-dispersible aldehyde component. The resulting copolymer gels are stable at low pH conditions, such as those of CO.sub.2 flood conditions.