Abstract: A method of flooding a petroleum reservoir by way of an injection well to aid in the recovery of hydrocarbons from a recovery well includes running a radioactive well logging tool in the injection well to derive a first well log of the reservoir in the vicinity of the injection well. The reservoir is then flooded with a solvent injected into the reservoir at a predetermined rate from the injection well. The radioactive well logging tool is again operated to derive a second well log. High salinity salt water is injected into the reservoir from the injection well. The radioactive well logging tool is run again to derive a third well log. The well logs are utilized to provide a record of the effectiveness of the solvent flood.

Abstract: In a method of recovering petroleum from underground formations penetrated by a production well, superheated steam and then hot hydrogen are injected by way of the well into a preheated formation zone next to the well. The hydrogen is injected under sufficient pressure to cause hydrogenation of the petroleum in the heated zone. The well is shut in and the hydrogen in the heated zone is allowed to "soak" for a period of time after which the pressure in the well is lowered and petroleum is recovered from the heated zone by way of the well. The cycle can be repeated a number of times.By way of another well spaced from the production well, fluid under pressure is injected into said formations to drive petroleum in said formations between the two wells to the production well for recovery. Hydrogenation of the petroleum occurs as it is driven through the heated zone in the presence of the hydrogen therein.

Abstract: The disclosed invention is a method for efficiently recovering viscous petroleum from hydrocarbon formations, particularly consolidated tar sand formations. A superheated paraffinic solvent under elevated pressure and temperature is injected into the formation. Thereafter, the formation is rapidly produced until pressure is depleted. The injection and production depletion cycle is then repeated.

Abstract: Improved methods and apparatus are provided for recovering high viscosity oils from a sub-surface earth formation utilizing horizontal well apparatus. A plurality of horizontal drill holes extend from a large diameter vertical shaft hole into the formation of interest. Steam may be injected into the formation through selectively placed conventional vertical wells terminating within the oil-bearing formation, while oil is recovered from the lateral drill holes. A noncondensible gas or cold water may be injected into the formation subsequent to steam injection to enhance the overall recovery of oil.

Abstract: Improved methods and apparatus are provided for recovering high viscosity oils from sub-surface earth formations. In particular, a large diameter shaft hole is employed and a plurality of substantially horizontal drill holes extend radially from the shaft hole into the formation. It is a feature of this invention to provide vertically spaced drill holes oriented to improve the recovery of the oil. Methods are provided for further enhancing oil recovery by coordinating the injected fluid with the location of injection within the formation.

Abstract: The production of hydrocarbons from a subterranean hydrocarbon-bearing formation containing acid-soluble components, such as one composed at least in part of dolomite or limestone, is stimulated by injecting into the formation usually via casing and cement pack perforations a composition comprising an aqueous solution of a mineral acid having dissolved therein a small amount of a vinylpyrrolidone polymer or an alkoxylated vinylpyrrolidone polymer. The increase in the permeability and porosity of the formation achieved utilizing the method of invention results in a substantial improvement in hydrocarbon recovery. Optionally, the injected composition may be saturated with natural gas at the injection pressure. In another embodiment this invention relates to the oxyalkylated vinylpyrrolidone polymer compositions.

Abstract: This invention relates to methods and systems for recovering high viscosity oils, petroleum substances and other minerals from subsurface earth formations. In particular, one or more large diameter shaft holes are provided which preferably terminate in an enlarged subterranean chamber. A plurality of drill holes are provided, with perforated piping which extend radially from the chamber into the formation, and from which oil and the like may be recovered. It is a particular feature of this invention to provide means and methods for injecting a mixture of steam and a noncondensable gas into the drill holes, whereby the driving mechanism of the formation may be selectively maintained or enhanced at the same time the viscosity of the oil in the formation is reduced.

Abstract: An improved miscible displacement oil recovery process, and particularly a vertical downward gas driven miscible blanket oil recovery process is disclosed. Reduction of temperature in the portion of the reservoir where miscible displacement is occurring reduces the pressure required to attain miscibility with a specified solvent-dry gas injection mixture; or at constant pressure, reduces the amount of solvent required to be injected to achieve a condition of miscibility. Cooling is achieved by chilling the solvent prior to injecting it into the reservoir, or cooling the high pressure dry gas injected into the reservoir, or both.

Abstract: A method for recovering hydrocarbons from a subterranean formation in which steam, for example, is injected into the formation via an injection well to drive the hydrocarbons toward a spaced production well. Water injected via the production well into an upper horizon of the formation is passed downwardly through the formation about the production well and then back into the production well at a lower horizon in the formation. A mixture of displaced hydrocarbons and injected water are then coproduced at the lower horizon thru the production well after which the hydrocarbons are recovered from the mixture. Optionally, a minor amount of a sulfated interfacial tension reducer may be introduced with the steam to promote increased hydrocarbon recovery.

Abstract: A process for recovering hydrocarbons from a subterranean formation in which in situ combustion is first initiated in the formation by injection of air, for example, through an injection well, the injection of air is terminated, carbon dioxide or nitrogen is injected into the formation via the injection well to displace unconsumed air and in a final step a mixture of carbon monoxide and hydrogen is injected into the formation where reaction of the carbon monoxide with steam generated from the formation water forms 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.

Abstract: The production of hydrocarbons from a subterranean hydrocarbon-bearing formation containing acid-soluble components, such as one composed at least in part of dolomite or limestone, is stimulated by injecting into the formation usually via casing and cement pack perforations a composition comprising an aqueous solution of a mineral acid having dissolved therein a small amount of a vinylpyrrolidone terpolymer. The increase in the permeability and porosity of the formation achieved utilizing the method of invention results in a substantial improvement in hydrocarbon recovery. Optionally, the injected composition may be saturated with natural gas at the injection pressure.

Abstract: Significant improvement in the recovery of hydrocarbons from a subterranean hydrocarbon-bearing calcareous formation is accomplished by injecting into the formation via an injection well drilled into a formation communicating with an adjacent producing well and containing acid-soluble components which may or may not have water-sensitive clays and shales included therein, a composition comprising an aqueous solution of a mineral acid having dissolved therein a small amount of a vinylpyrrolidone terpolymer solution whereupon the acid solution reacts with the acid-soluble components of the formation creating passageways or enlarging existing passageways thus facilitating the flow of fluids therein and thereby increasing the recovery of hydrocarbons from the formation through the adjacent producing well. Optionally, the injected composition may be saturated with natural gas at the injection pressure.

Abstract: A two-step method for recovering hydrocarbons from a subterranean formation in which in situ combustion is first initiated in the formation by injection of air, for example, through an injection well, the injection of air is terminated and in a final step a combustion-supporting gas such as air, air mixed with oxygen, etc. and a combustible gas such as hydrogen, carbon monoxide and mixtures thereof are introduced into the formation preferably through separate sets of casing perforations and finally hydrocarbons are recovered via a production well.

Abstract: A process for recovering hydrocarbons from a subterranean formation in which in situ combustion is first initiated in the formation by injection of air, for example, through an injection well, the injection of air is terminated, carbon dioxide or nitrogen is injected into the formation via the injection well to displace unconsumed air and in a final step a mixture of carbon monoxide and hydrogen is injected into the formation where reaction of the carbon monoxide with steam generated from the formation water forms 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.

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 method for recovering viscous hydrocarbons from subterranean formations involves injecting a hydrocarbon solvent into the formation at spaced intervals to produce permeable regions or streaks in the formation. The injection is preferably directed to those regions of highest oil saturation, i.e., those regions with lowest effective permeability. A subsequent introduction of a heated fluid then will enable recovery of the viscous hydrocarbons in the treated regions and the untreated zones therebetween.

Abstract: A method for recovering hydrocarbons from a subterranean formation in which steam, for example, is injected into the formation via an injection well to drive the hydrocarbons toward a spaced production well. Water injected via the production well into an upper horizon of the formation is passed downwardly through the formation about the production well and then back into the production well at a lower horizon in the formation. A mixture of displaced hydrocarbons and injected water are then coproduced at the lower horizon thru the production well after which the hydrocarbons are recovered from the mixture. Optionally, a minor amount of a sulfated interfacial tension reducer may be introduced with the steam to promote increased hydrocarbon recovery.

Abstract: A two-step method for recovering hydrocarbons from a subterranean formation in which in situ combustion is first initiated in the formation by injection of air, for example, through an injection well, the injection of air is terminated and in a final step a combustion-supporting gas such as air, air mixed with oxygen, etc. and a combustible gas such as hdyrogen, carbon monoxide and mixtures thereof are introduced into the formation preferably through separate sets of casing perforations and finally hydrocarbons are recovered via a production well.

Abstract: Methods and mechanisms are disclosed comprising means for mixing only water with crude oil at temperatures above 32.degree. F. until the inversion point is crossed where a lower viscosity emulsion consisting of oil-in-water is formed for reducing resistance to flow of crude oil up from deep in a well to the surface, or through a pipeline. This oil-in-water emulsion consists of, by volume, 5 percent to 15 percent oil and 95 percent to 85 percent water.

Abstract: Disclosed is an oil recovery method especially useful for recovering viscous oil from thick formations including tar sand deposits. The method comprises several phases which accomplish efficient recovery of the viscous oil from the formation with good vertical and horizontal sweep conformance or effectiveness. The first phase may utilize as few as two spaced apart wells, one for fluid injection and one for oil production and an oil recovery method such as injecting steam or a mixture of air and steam for low temperature, controlled oxidation is a preferred fluid for use in the first phase. After fluid breakthrough at the production well occurs, the producer of the first phase is converted to an injection well and one or more new production wells outside of the pattern swept by the injected fluid are completed in the oil formation. Thermal recovery fluids are then injected into two wells with the displacement moving in the direction of the new production wells.