Abstract: A method of selectively blocking high permeability flow channels in an underground hydrocarbon material bearing formation having flow channels of high permeability and having flow channels of lesser permeability.

Abstract: A method for restricting fluid flow in depth outwardly from the bore hole through the medium to high permeable zones of a subterranean reservoir of nonuniform permeability in which there is injected into the reservoir aqueous solutions of a water-soluble polymer and an alkali metal silicate. The injected solutions are either admixed at the surface prior to injection, simultaneously injected or injected sequentially.

Abstract: A method of heating a hydrocarbon material contained in a recovery zone in an underground hydrocarbon material-bearing formation to reduce the viscosity thereof for facilitating recovery of the hydrocarbon material, in which a gaseous penetration medium comprising a gaseous working fluid and a carrier gas, is fed into the formation at a penetration pressure sufficient for penetration of the recovery zone, the working fluid being a water soluble gas which generates heat of solution upon absorption in an aqueous medium, and in which the partial pressure of the working fluid in relation to the penetration pressure and the temperature prevailing in the recovery zone is controlled to inhibit working fluid condensation but to provide for absorption of working fluid by water present in the formation to release heat for heating the hydrocarbon material in the recovery zone.

Abstract: An aqueous caustic solution and an aqueous solution containing a polyvalent cation dissolved therein are sequentially injected into the near well bore environment of a subterranean sandstone formation interposed by an aqueous spacer. The aqueous caustic solution is caused to reside within the near well bore environment for a period of time sufficient to allow the caustic to interact with the sandstone formation so as to cause a portion of the caustic injected to be held within the near well bore environment. The subsequently injected polyvalent cation and the portion of caustic react within the near well bore environment and form an insoluble precipitate which preferentially reduces the permeability of the relatively highly permeable zones in the near well bore environment thereby improving vertical conformance and flow profiles of fluids subsequently injected into or produced from the formation.

Abstract: A duct-forming device is disclosed for use in a well completion apparatus of the kind, wherein a bore hole casing is positioned in a bore hole and duct-forming devices of alkali- and acid-resistant metal--such as steel--are secured at spaced levels to the casing in alignment with holes machined in the casing wall. In accordance with the invention, a closure device is arranged within the duct-forming device which permits flow of predetermined amounts of liquid, such as acid, from the interior of the casing through the duct-forming device and into the producing formation, while gradually being moved by the liquid into a position in which such fluid flow is prevented.

Abstract: A method is disclosed for reducing formation plugging impurities in a sulfonate surfactant used in enhanced oil recovery operations which comprises contacting said surfactant with an effective amount of an aldehyde having from 1 to about 18 carbon atoms. In a preferred instance, a method is disclosed for the treatment of sulfonate surfactants useful in enhanced recovery processing to substantially reduce the formation plugging impurities, typically inorganic sulfite salts.

Abstract: Highly conductive subterranean zones are treated with aqueous fluids containing gel-forming amounts of water-soluble lignosulfonate and silicate. Suitable treating fluids contain about 2 to about 5 weight percent sodium or ammonium lignosulfonate and sodium silicate at a weight ratio of SiO.sub.2 to lignosulfonate of about 0.2 to about 1.

Abstract: Fresh water solutions of pectic materials are injected into high permeability zones in the subterranean reservoir wherein said materials upon contact with brine solutions form thick gels for the purpose of reducing the permeability of these high permeability zones thereby improving the vertical conformance efficiency of flooding operations within the reservoir.

Abstract: A debilitating agent is injected into a subterranean formation under conditions of time and injection rates such that it permeates both the more permeable zones and the less permeable zones. A flush is then injected under conditions of time and rate so as to selectively remove the debilitating agent from the more permeable zones. In one embodiment the debilitating agent is a polymerization inhibitor or poison. Then a material which will polymerize in the absence of the poison or inhibitor is injected. Since the poison or inhibitor will remain in the less permeable zones, little or no polymer is formed there. In the more permeable zones from which the poison has been flushed, polymerization occurs so that subsequently injected secondary or tertiary oil recovery fluids are diverted away from the thief zones to more effectively displace the oil from the less permeable zones.

Abstract: Data useful for evaluating the effectiveness of or designing an enhanced recovery process said process involving mobilizing and moving hydrocarbons through a hydrocarbon bearing subterranean formation from an injection well to a production well by injecting a mobilizing fluid into the injection well, comprising(a) determining hydrocarbon saturation in a volume in the formation near a well bore penetrating formation,(b) injecting sufficient mobilizing fluid to mobilize and move hydrocarbons from a volume in the formation near the well bore, and(c) determining the hydrocarbon saturation in a volume including at least a part of the volume of (b) by an improved single well surfactant method comprising injecting 2 or more slugs of water containing the primary tracer separated by water slugs containing no primary tracer.

Abstract: A method of treating a subterranean formation which has undergone an in situ leaching operation which utilzed an ammonium solution as the lixiviant. In such a leach operation, ammonium ions will exchange into the clay in the formation and will present a threat of contamination to any ground waters that may be present in the formation. The present method involves flushing the formation with a halogenated restoration fluid, e.g., chlorinated water having a halogen therein which reacts with ammonia within the formation to decompose the ammonia to nitrogen. The halogenated restoration fluid can be continuously injected or it can be injected as a slug followed by a relatively halogen-free solution to complete the operation. The ammonia concentration of the produced fluids is monitored and when it drops below a desired value, the method is complete.

Abstract: This invention relates to the recovery of oil from underground deposits. The invention relates to novel gel compositions consisting of water, a polysaccharide polymer, an acid generating salt and a melamine resin. The invention also relates to the method of utilizing said composition to recovery underground oil.

Abstract: A two-step process for recovering hydrocarbons from a subterranean formation in which the formation is first heated by injecting steam at a temperature of about 500.degree. to about 1500.degree. F. through an injection well and in a second step a mixture of carbon monoxide and hydrogen is pressured into the formation via the injection well where in the heated formation reaction with the carbon monoxide and steam takes place forming additional hydrogen and carbon dioxide and finally hydrocarbons are recovered via a production well. Optionally, after injection of the mixture of carbon monoxide and hydrogen into the formation has been terminated, the heat stored in the formation may be recovered by injecting water, as a drive fluid into the formation via the injection well.

Abstract: A process of treating a plurality of wells involved in an enhanced oil recovery process so that oil and/or gas can be displaced from a reservoir in a more uniform manner comprising treating the formation surrounding and in the immediate vicinity of each well involved in the process with a solution that sets with time to form a plug in the more permeable zones of the reservoir surrounding each well.

Abstract: An enhanced oil recovery process for subterranean reservoirs wherein there is injected into the reservoir a relatively large slug of a dilute aqueous alkali metal silicate solution. It is optional to follow the silicate solution with an aqueous drive fluid. In treating heterogeneous reservoirs, it is further optional, prior to injecting the large slug of silicate solution, to inject one or more small slugs of the silicate solution alternately with one or more small slugs of a dilute aqueous solution of an agent that reacts with the alkali metal silicate to form a gelatinous precipitate. In the latter instance a small spacer slug of water is injected between successive slugs of the reactant solutions to separate the reactants during injection.

Abstract: A process for recovering oil from a heterogeneous subterranean reservoir having strata of widely varying permeability by injecting therein via a well a slug of a micellar solution followed by an aqeuous drive fluid wherein, at some time prior to the injection to all of the slug of the micellar solution, there is injected into the reservoir one or more aqueous solutions of reagents that react in the reservoir to form a plugging material, one of which reagents contains a polyvalent cation. After the plugging material has formed, the well is produced to remove from the reservoir the unreacted reagent containing a polyvalent cation which polyvalent cation would otherwise react with and reduce the efficiency of the subsequently injected micellar solution.

Abstract: A method of producing a hydrocarbon or hydrocarbons is disclosed. The method employs carbon containing material, water and a reaction chamber in a hot subterranean formation. The method steps include:(a) forming an aqueous slurry containing said material in divided, flowable form,(b) passing the slurry into said subterranean formation for chemical interaction of said material at said elevated temperature to form said hydrocarbon, and(c) recovering said hydrocarbon.

Abstract: A method of terminating the flow of formation fluids from an uncontrolled well comprising introducing a low viscosity fluid into the formation having the property of subsequently becoming highly viscous whereby the portion of the formation adjacent the uncontrolled well is surrounded by highly viscous fluid which blocks the flow of formation fluids to the uncontrolled well.

Abstract: The instant invention is concerned with the use of organic acid chrome complexes for stabilizing a formation against clay swelling and particle migration and, in one embodiment, to improve oil recovery by rendering watered out channels within a produced formation water repellent and oil wettable.

Abstract: Disclosed is method for treating a high permeabiity communication channel between wells for use in a viscous oil recovery method to stabilize fine particulate matter present in the communication channel to prevent movement of fine particles during the oil recovery process. The communication channel is formed by fracturing or sweeping with air followed by introducing a viscous oil displacing medium such as a solvent or steam to desaturate the previously fractured or air swept zone in the formation, converting it into a high permeability channel between wells. In order to stabilize the fine grain sand and other minerals present in the communication channel to prevent migration thereof which results in loss of permeability of the communication channel, the channel is treated with a hydroxy aluminum solution and allowed to age for a period of time sufficient to form crystalline aluminum hydroxide which cements the grains together while maintaining permeability of the communication channel.

Abstract: A method for reducing the quantity of water produced from a well bore-penetrated subterranean formation and for increasing the production rate of fluid hydrocarbons produced from said formation. Said method comprises injecting into said formation an aqueous solution of a partially hydrolyzed polyacrylamide, and contacting said polyacrylamide in situ with an aqueous solution containing divalent and/or trivalent metal cations.

Abstract: Improved injectivity profiles and/or vertical conformance in flooding heterogeneous formations containing high permeability zones is obtained by injecting an aqueous polyacrylamide solution and an aqueous formaldehyde solution into the formation and allowing the polyacrylamide to react with the formaldehyde in the relatively high permeability zones to form a gel. Thereafter, improved sweep efficiency is realized in displacing hydrocarbon from the lesser permeability zones.

Abstract: The hydrogen sulfide concentration and total sulfur concentration of a gas of relatively higher hydrogen sulfide and total sulfur concentration are reduced by combining hydrogen sulfide in the gas with oxygen in the presence of a fragmented permeable mass of particles containing oil shale treated to remove organic materials to yield a gas with relatively lower hydrogen sulfide and total sulfur concentration for withdrawal from the fragmented permeable mass.

Abstract: The hydrogen sulfide concentration of a gas is reduced by reacting hydrogen sulfide in the gas with oxygen in the presence of raw oil shale. The ratio of sulfur dioxide to sulfur produced by this reaction depends upon the molar ratio of oxygen to hydrogen sulfide present. Sulfur is the predominant product when hydrogen sulfide is reacted in the presence of oil shale with less than about 1 mole of oxygen for each 2 moles of hydrogen sulfide.

Abstract: Petroleum may be recovered from subterranean, petroleum-containing formations by injecting into the formation an organic liquid having dispersed therein, an alkali metal in very fine, preferably colloidal size range, particular form. The organic liquid containing the alkali metal dispersion is followed by injecting an aqueous fluid to react with the alkali metal, generating alkali metal hydroxide, hydrogen gas and heat in the formation which stimulates displacement of the petroleum by encouraging formation of low viscosity oil-in-water emulsions, as well as by thermal viscosity reduction effects, and dissolution of hydrogen gas in the viscous petroleum. The organic liquid having alkali metal dispersed therein may be preceded or followed by injecting crude petroleum from another formation which is prone to emulsify spontaneously and aid in the formation of low viscosity oil-in-water emulsions.

Abstract: The hydrogen sulfide concentration of a gas of relatively higher hydrogen sulfide concentration is reduced by combining at a temperature less than about 650.degree. F hydrogen sulfide in the gas with oxygen in the presence of a fragmented permeable mass of particles containing oil shale to yield a gas with relatively lower hydrogen sulfide concentration for withdrawing from the fragmented permeable mass.

Abstract: An enhanced oil recovery process for subterranean reservoirs wherein there is injected into the reservoir a relatively large slug of a dilute aqueous alkali metal silicate solution. It is optional to follow the said silicate solution with an aqueous drive fluid. In treating heterogeneous reservoirs, it is further optional to also inject a small slug of a dilute aqueous solution of an agent that reacts with the alkali metal silicate to form a gelatinous precipitate. In the latter instance a small spacer slug of water is injected between successive slugs of the reactant solutions to separate the reactants during injection.

Abstract: A method of treating a subterranean formation which has undergone an in situ leaching operation which utilized an ammonium carbonate and/or bicarbonate lixiviant. In such a leach operation, ammonium ions will absorb onto the clay in the formation and will present a threat of contamination to any ground waters that may be present in the formation. The present method involves flushing the formation with a strong, basic solution, e.g., sodium or calcium hydroxide, to convert the ammonium ions to ammonia which is easily carried from the formation by the basic solution. After substantially all of the ammonium ions are removed, the formation is then flushed with water to remove any basic solution which may remain in the formation.

Abstract: A method of forming a mixed plug in the more permeable zones of a subterranean reservoir of nonuniform permeability in which there is injected into the reservoir aqueous solutions of: a polymer, a material that reacts with the polymer to form a time-delayed polymer-containing plug, an alkali metal silicate and a material that reacts with the silicate to form a time-delayed silicate-containing plug. The injected solutions are either admixed at the surface prior to injection or are simultaneously injected so that a mixed polymer-silicate plug is formed in the reservoir.

Abstract: A process for recovering petroleum from subterranean reservoirs where high salt content water is used in a secondary recovery process consisting of forming as the displacement fluid a dilute alkaline silicate solution utilizing the high salt content water and filtering the alkaline flooding solution to remove scale-forming alkali insoluble salts which include a substantial proportion of calcium and magnesium salts. The filtered solution is injected into the reservoir and this is followed by an injection of a slug of substantially neutral water. A dilute acid solution is utilized to contact and dissolve the alkaline insoluble salts which have been filtered from the alkaline solution and the thus formed solution which includes a substantial portion of soluble calcium and magnesium salts is injected into the reservoir for subsequent contact with the alkaline silicate solution.

Abstract: A composition of matter comprising water, a polymer capable of being crosslinked by polyvalent metal cations, a reducible species containing said polyvalent metal in a higher oxidation state, and a reducing agent selected from among KI, MnCl.sub.2, Mn(NO.sub.3).sub.2, and K.sub.4 Fe(CN).sub.6 which composition is capable of forming a gel by crosslinking is provided. A method is also provided for in situ gel formation using this crosslinking composition. In one of its embodiments a method is provided for increasing the rate of gel formation by the addition of H+ ion.

Abstract: A process is provided for reducing water production in production oil wells or for altering the water permeability profile of injection wells that have been previously treated with partially gelled or ungelled polymer and from which oil has been produced for a period of time subsequent to the treatment. The retreatment is made by injecting into the formation an ionic solution capable of crosslinking residual ungelled polymer in the formation and thereafter injecting into the formation an aqueous solution of polymer capable of being crosslinked by the ionic solution. In a preferred embodiment aluminum citrate is injected into an underground formation that has previously been treated with an ungelled polymer selected from among polyacrylamides, partially hydrolyzed polyacrylamides, polysaccharides, carboxymethylcellulose, polyvinyl alcohol, polystyrene sulfonates, and the like, with the aluminum citrate being followed with a solution of an at least partially ungelled polymer selected from those above named.

Abstract: This specification is directed to a method of producing oil from an oil-containing subterranean formation by a caustic waterflood. Oil containing carboxylic acids is passed through an ion-exchange resin to selectively remove the carboxylic acids therefrom. The removed carboxylic acids are injected into the formation in conjunction with the caustic waterflood to enhance the production of oil from the formation.

Abstract: Oil recovery efficiency of tertiary oil recovery processes using a micellar solution as the displacement fluid is improved by injecting a dilute aqueous solution of an alkali metal silicate into the reservoir subsequent to the micellar solution injection and prior to the drive fluid injection. The alkali metal silicate has a M.sub.2 O/SiO.sub.2 ratio of between 1 and 4.

Abstract: A process for recovering oil from subterranean oil-bearing formations which entails the use of a water treating medium. The water treating medium comprises an acrylamide-acrylic acid copolymer formed by hydrolyzing a water-in-oil emulsion containing from 2-75% by weight of finely divided acrylamide polymer to the extent that between 0.8 and about 67% of the amide groups originally present in the acrylamide polymer are converted into carboxyl groups.

Abstract: A method of selectively plugging permeable water-producing zones in a subterranean formation of nonuniform permeability comprising sequentially injecting into the formation (1) an aqueous solution of a first reactant material rendered more viscous than the subsequently injected liquids by the addition of a viscosity increasing agent, (2) a low viscosity inert aqueous spacer liquid, (3) a low viscosity aqueous solution containing a second reactant material which, on contact, will react with the first reactant material to produce an insoluble precipitate, (4) a low viscosity inert aqueous spacer liquid and (5) an additional amount of the aqueous solution of a first reactant material, which aqueous solution is optionally rendered more viscous than the previously injected aqueous solution containing the second reactant material by the addition thereto of a viscosity increasing agent.

Abstract: A well completion and packer fluid additive consisting essentially of carboxymethyl cellulose crosslinked with an inorganic chromium compound. The fluids prepared with this procedure have temperature stability to 250.degree. F., excellent resistance to contamination, stability in electrolyte solutions such as KCl and CaCl.sub.2 and upon acidizing the fluid retains less the 3% residue.

Abstract: A method of forming a combination plug in the more permeable zones of a subterranean formation of nonuniform permeability in which there is injected into the formation (1) aqueous solutions of a polymer and a material that reacts with the polymer to form a polymer-containing plug and (2) thereafter injecting aqueous solutions of an alkali metal silicate and a material that reacts with the silicate to form a silicate-containing plug.

Abstract: A method for plugging the more permeable strata of a subterranean formation of nonuniform permeability in which an aqueous solution of a gelling agent and an aqueous solution containing both a gelling agent and an alkali metal silicate are injected into the formation. The two solutions can be injected in any order, and are separated by a slug of an inert aqueous spacer liquid. The first injected solution preferably also contains a polymer thickener.

Abstract: Aqueous solutions comprising polyethylenimine as the active ingredient thereof are injected into an underground formation having an acidic crude oil therein. The polyethylenimine reacts with the nonhydrocarbon constituents in the crude oil to form a surface-active material. The surfactant emulsifies in the oil to form a grease-like barrier layer, and the crude may then be pushed by a suitable pushing agent such as water or viscous water from behind the grease barrier, to a producing well from where the crude oil is produced.

Abstract: An improved process for decreasing the permeability of a subterranean oil-bearing formation which comprises injecting an aqueous surfactant solution containing a chemically crosslinkable, water-dispersible polymer which prevents the surfactant from foaming until it is in the formation and after the polymer breaks down due to heat in the formation caused by steam which is used to carry the aqueous solution into the formation. In accordance with one embodiment, gelled or ungelled cellulose ether polymers in an aqueous surfactant solution are injected with steam into the more permeable or more depleted portions of a subterranean oil-bearing formation to produce a selective blocking due to the formation of foam in the more permeable sections of the formation which forces the remaining injection steam to produce oil from less depleted portions of the formation.

Abstract: A method is provided for obtaining good residual resistance factor at relatively low ratios of crosslinking agents to polymer for plugging fractured or porous media using a method of injecting into the formation a first aqueous polymer solution followed by an injection of crosslinking agents capable of gelling the polymer solution and thereafter injecting a second aqueous polymer solution that is capable of being gelled by the crosslinking agents. In each of the aqueous polymer solutions the polymer is already partially crosslinked before the polymer solution is injected into the formation. This process is applicable to production wells and injection wells.

Abstract: Improvements in secondary recovery operations for the recovery of oil, and improvements in well drilling operations, are accomplished through the use of aqueous gels exhibiting high gel strength prepared from water and a mixture of (a) at least one cellulose ether, e.g., carboxymethyl cellulose, and (b) at least one polyacrylamide.

Abstract: In a subterranean reservoir, a strata or zone of high permeability as compared to other stratas of the reservoir may be plugged by forming a solid gel in situ within the highly permeable strata. The gel plug is formed by injecting a colloidal silica suspension into the strata which is in a liquid state and contacting the suspension in situ with a surfactant. Upon mixing with the surfactant, the colloidal silica suspension forms a gel which effectively plugs the highly permeable zone blocking further fluid flow through the zone.

Abstract: An improved anionic waterflood additive is prepared by partially chlorinating a normal alkane having about 10 to about 18 carbon atoms to about 2 to about 15 weight percent chlorine content, employing the chlorinated alkane to alkylate an aromatic hydrocarbon, such as benzene; sulfonating the thus formed alkylate or a fraction thereof to form a sulfonic acid; converting the sulfonic acid to a sulfonate by reacting with a base component, such as an alkali metal hydroxide, ammonium hydroxide, or an alkali metal carbonate; and overbasing the sulfonate by admixing with an excess of base component such that the ratio: "weight of excess base component/weight of sulfonate" is about 0.03 to about 3.0. The anionic waterflood additive is injected into a petroliferous formation, the formation is waterflooded, and oil is recovered.

Abstract: An improved anionic overbased waterflood additive comprises a base component, a first sulfonate component derived from an alkylation reaction product employing a branched-chain alkene as the alkylating agent, and a second sulfonate component derived from an alkylation reaction product employing a partially chlorinated normal alkane as the alkylating agent, wherein the base component is present in the weight ratio range of 3/100 to 300/100, base component to total sulfonate, and wherein the weight ratio of the first sulfonate component to the second sulfonate component is in the range of 1/9 to 9/1. The overbased waterflood additive may be formed prior to injection into a petroliferous formation or may be formed in situ by first injecting the total sulfonate followed by the base component.

Abstract: A method for reducing subterranean formation permeability to brines wherein the formation is penetrated by at least one well bore comprising, injecting into the formation two slugs of an aqueous polymer solution interspaced with a brine slug. A method for reducing the quantity of water recovered from a subterranean formation which is penetrated by at least one well bore wherein in one embodiment prolonged mobility control and/or plugging is maintained with the injection into the formation of slugs of aqueous solutions of at least two distinguishable viscosity increasing agents separated by a brine spacer slug.

Abstract: Disclosed is a process for recovering petroleum from subterranean, viscous asphaltic or bituminous petroleum-containing formations, including subterranean tar sand deposits. A zone of gas permeability is established in the formation first, such as by fracturing or gas sweeping a section of the formation. Oxidizing gas such as oxygen, air, oxygen enriched air, ozone, or chlorine, or a mixture of steam and an oxidizing gas is introduced into the zone of increased gas permeability to expand the zone and further to cause a reaction to occur between the oxidizing gas and the oxygen-susceptible groups or labile groups associated witn the bituminous or asphaltic petroleum molecules forming acidic or aldehyde groups. Next, a gaseous or liquid alkalinity agent such as ammonia is introduced into the formation to react with the oxidatively pre-treated groups in the bituminous or asphaltic petroleum to form surface active agents or surfactants in situ.

Abstract: Improvements in secondary recovery operations for the recovery of oil, and improvements in well drilling operations, are accomplished through the use of aqueous mediums comprising aqueous gels prepared from water and certain polymers such as polyacrylamides and related polymers.

Abstract: A method for recovering hydrocarbons by injecting a mixture of oxidizing gas and steam into a lateral conduit in a hydrocarbon-containing formation to produce a product gas and, based on values contained in such gas, controlling the reactions between mixtures of oxidizing gas and steam and hydrocarbons in the formation to optimize the Btu value of the product gas.