Abstract: In an enhanced oil recovery process utilizing a plurality of wells disposed in a nearly square grid wherein a plurality of these wells are injection wells which are utilized to inject a fluid into a petroleum reservoir, said fluid being then forced through the reservoir towards a plurality of production wells from which the fluid and mobilized petroleum from the reservoir are produced, an improvement is added comprising utilizing the wells at the corners of each nearly square grid as injection wells, drilling two additional wells within each grid along one diagonal and then utilizing these two additional wells as new production wells.

Abstract: An in-situ combustion method for oil recovery from a subterranean oil-bearing formation traversed by a plurality of wells comprising a series of well pattern units wherein air permeability is established sequentially in the individual well pattern units pior to the initiation of in-situ combustion, thereby resulting in an increase in overall sweep efficiency.

Abstract: The vertical conformance of a steam drive process is improved and steam override reduced by penetrating the recovery zone between one injection well and one producing well, with at least one infill well which is in fluid communication with no more than the bottom half of the formation. Steam or a mixture of steam and hydrocarbon is injected into the injection well and fluids including oil are recovered from the producing well until live steam production occurs at the producing well. Petroleum production is then begun at the infill well and continued until the water cut of the fluids being produced from the infill well reaches 95 percent. The infill well is converted from a producer to an injector and hot water or cold water followed by hot water is injected into thelower portion of the formation via the infill well and fluids are produced from the production well. By this means, oil is recovered from the lower portions of the formation between the infill well and the production well.

Abstract: The vertical or both vertical and horizontal conformance of a steam drive process is improved and steam override reduced by penetrating the zone between one injector and one producer, with one or more infill wells in fluid communication with the bottom half or less of the formation, and producing petroleum from the infill well after steam channeling has occurred at the production well. After the water cut of the fluids being produced from the infill well reaches 95 percent, the infill well is converted from a producer to an injector and steam is injected into the infill well and fluids are recovered from the production well. When one infill well is employed in a more or less aligned arrangement between injection and production wells, the vertical conformance is improved. When one or more infill wells are positioned in an offset or nonaligned arrangement relative to each injector and producer, conformance in both the horizontal and vertical planes is improved.

Abstract: The vertical conformance of a steam drive process is improved and steam override reduced by penetrating the zone between one injector and one producer, with an infill well located between the injector and producer which is in fluid communication with no more than the bottom half of the formation. Steam is injected into the injection well in the first phase with production of fluids from the upper 1/3 or less of the formation via the production well. A separate flow path in communication with the bottom 1/3 or less of the formation is provided in the producing well, and is used during the first phase for push-pull treatment of the formation with solvent and steam or hot 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.