Abstract: A process to temporarily seal an upper zone of higher permeability. Coiled tubing is used to cover a zone of lower permeability with a gel block containing rock salt. A lower density, more stable, slower yielding gel block having a gel breaker is squeezed into the upper zone. The well is shut-in and the low density gel plug becomes rigid. Water is then circulated down the coiled tubing to dissolve the high density gel block out of the wellbore and re-open lower perforations which allows the low permeability interval to be treated.

Abstract: A process where massive hydraulic fracturing (MHF) is used in combination with a novel horizontal and vertical well drilling scheme. The novel well drilling scheme provides the cost benefits of vertical drilling along with the increased pay zone contact of extended-reach drilling. MHF additionally provides for substantially enhanced reservoir drainage.

Abstract: A method for improved matrix acidizing of a sandstone formation containing a perforated well. Initially, a "pre-pad" and a temperature stable viscous gel pad are pumped into the formation via said well at injection pressures greater than 5 BPM while monitoring surface pressures. Next, an acid suitable for acidizing the formation is pumped into the formation while the injection pressure is maintained. Thereafter, additional stages of viscous pad and acid are pumped into the formation to ensure zonal coverage and acid-stimulation.

Abstract: This specification discloses a method of hydraulic fracturing a subterranean formation wherein two horizontally spaced-apart wells are provided and completed to communicate with the formation. Hydraulic fluid pressure is sequentially applied to create and propagate vertical fractures into the formation and to create a vertical fracture that communicates both wells.

Abstract: This invention is directed to a method for recovering residual oil from produced fines and solid materials which are obtained during the production of viscous oil from a formation. The fines and produced materials are injected into a formation with or without fracturing for their disposal. Once in the formation, a non-thermal enhanced oil recovery method is used to remove residual oil from the fines or solid materials. Use of this method provides an inexpensive and environmentally safe method for recovering residual oil from formation fines or solids.

Abstract: This specification discloses a method of hydraulic fracturing a subterranean formation wherein two horizontally spaced-apart wells are provided and completed to communicate with the formation. Hydraulic fluid pressure is sequentially applied to create and propagate vertical fractures into the formation and to create a vertical fracture that communicates both wells. This specification further disclosed the creation of an enhanced fracture drainage pattern in a hydrocarbon-bearing formation and producing hydrocarbons from the formation via a single producing well.

Abstract: This invention is directed to a method to improve fracture acidizing in a carbonate containing formation. Initially, the formation is hydraulically fractured so as to form a fracture in the formation in a preferred direction. Thereafter, an acid is directed into the fracture so as to etch the fracture's face and create channels therein. Afterwards, a viscous fluid is directed into the fracture which fluid contains a material sufficient to serve as a diverter and prevent growth in the existing fracture. Once the diverting material is in place, hydraulic fracturing is again conducted within the existing fracture whereupon fracturing forces are directed away from the diverter so as to form a branched fracture to contact hydrocarbonaceous vugs in the formation. The steps of fracturing acidizing, and diverting are continued until a vuggy area in the formation has been interconnected with the fracture system.

Abstract: A method for fracturing a subterranean formation containing desired natural resources in which controlled pulse fracturing (CPF) is combined with hydraulic fracturing in a second wellbore along with hydraulic fracturing in a first wellbore. Multiple radial vertical fractures are created by CPF in the second wellbore by a solidifiable gel material which is directed into created fractures during a subsequent hydraulic fracturing procedure. During this procedure, multiple vertical hydraulic fractures initiate in and propagate away from CPF created fractures thereby bringing the second wellbore fracture system into fluid communication with the fracture system of the first wellbore.

Abstract: This specification relates to the control of earth fines that are produced with hydrocarbons from a hydrocarbon-bearing formation into a well that penetrates the hydrocarbon-bearing formation. More particularly this specification relates the control of fines from a heavy-oil reservoir that is stimulated by thermal techniques and penetrated by and in communication with a well that is highly deviated from the vertical.

Abstract: A method for the disposal of waste water in a formation having varying permeability zones therein where a higher permeability zone is first closed to fluid flow via a solidifiable gellable mixture. This mixture forms a solid gel in the higher permeability zone. Afterwards, waste water is injected into a zone of lesser permeability which allows increased amounts of water to be placed into the formation.

Abstract: This invention is directed to a method to improve matrix acidizing of a carbonate containing formation by taking advantage of wormholes which are created during acidizing. The wormholes are closed with a solidifiable gel which protects them from entry of additional acid. The solidifiable gel is allowed sufficient time to form a solid. After a solid gel is formed, additional acid is directed into the formation where it moves past the wormholes containing the solid gel. Thereafter, an additional volume of solidifiable gel is directed into the formation where it protects any subsequently formed wormholes and diverts the acid further into the formation. An additional volume of acid is directed into the formation and the steps repeated until the formation has been acidized to obtain a desired degree of permeability.

Abstract: A method for limiting a downward growth of one or more vertically oriented fractures in a subterranean formation during a fracturing treatment. Initially, a first fracturing fluid with a known density is introduced into a formation having at least one fracture. The first fracturing fluid comprises a cross-linked gel composition sufficient to form a viscous gel in the fracture and also contains gel breakers. Thereafter, a second fracturing fluid is introduced into the fracture. This second fracturing fluid has a density lower than said first fracturing fluid. Additionally, the second fracturing fluid contains a proppant. The second fracturing fluid is continually introduced into the fracture thereby displacing the first fracturing fluid into a lower portion of the fracture where a substantially viscous gel forms.

Abstract: A method to improve the displacement efficiency of hydrocarbonaceous fluids from a formation where at least two horizontal perforated wellbores are utilized. One horizontal wellbore is placed at a lower level and another is placed at a higher level in said formation. Thereafter, a first displacement liquid immiscible with and having a density greater than hydrocarbonaceous fluids in said formation is injected into said lower horizontal wellbore. Afterwards, a second hydrocarbon immiscible displacement liquid having a density greater than said first liquid is injected into said lower wellbore. The second liquid displaces said first displacement liquid and hydrocarbonaceous fluids to said higher level in the formation. Subsequently, the displacing liquids and hydrocarbonaceous fluids are produced to the surface.

Abstract: A method for disposing of drilling wastes where an aqueous saline solution is used to disperse a drilling fluid or mud. The saline solution containing the dispersed drilling fluid or mud is injected into a disposal well or high permeability oil depleted zone. An interval of the formation adjacent to the disposal well is hydraulically fractured so as to allow continued injection of the solution containing the drilling fluid or mud at substantially low pressures. Hydraulic fracturing is used to re-establish communication with a disposal zone whenever a "skin" builds up due to filtration of the solids from the injected drilling fluids or muds.

Abstract: A method of protecting casing during high pressure well stimulation. An annulus between the casing and tubing is loaded with water via a small volume of nitrogen to partially displace annular fluid down the annulus and up the tubing. This loading takes place prior to setting a packer. Loading in this manner results in a gas "cushion". If the tubing should burst during high pressure stimulation, compression of the "cushion" will prevent the casing from rupturing.

Abstract: A method for controlling formation fines when producing heavy oil from an unconsolidated sand formation where at least two wells are utilized. Both wells are perforated and hydraulically fractured at a lower interval via a viscous gel fluid having a sized and high temperature resistant proppant therein. The proppant is a size sufficient to filter fines from the oil, thereby keeping the fracture clear. Cyclic steam injection and oil production are conducted in one well, while the other is shut-in. This sequence is continued until a desired amount of solids free hydrocarbonaceous fluids have been produced from the lower interval. Thereafter the lower interval is blocked off mechanically while cyclic steam injection and oil production are conducted in one well and the other well is shut-in until a desired amount of solids free hydrocarbonaceous fluids have been produced from a higher interval.

Abstract: A method for controlling formation fines when producing heavy oil from an unconsolidated sand formation where at least two wells are utilized. Both wells are perforated and hydraulically fractured at a lower interval via a viscous gel fluid having a sized and high temperature resistant proppant therein. The proppant is a size sufficient to filter fines from the oil, thereby keeping the fracture clear. Cyclic steam-flooding and oil production are conducted in one well, while the other is shut-in. This sequence is continued until steam breaks through at the lower interval from a first well into a second well. Afterwards, production packers with knock-out plugs are used to isolate the lower interval of both wells. Cyclic steam injection and oil production are continued in the upper interval of both wells. Subsequently, both wells are shut-in and production strings are directed to the lower formation interval through the knock-out plugs.

Abstract: A method for controlling formation fines when producing viscous oil from a consolidated or loosely consolidated formation having at least two wells therein. Both wells are perforated and hydraulically fractured at a lower level via a viscous gel fluid having a size and temperature resistant proppant therein. The proppant is of a size sufficient to filter formation fines from the oil. Cyclic steam-flooding and oil production are continued in one well, while the other well is shut-in. Prior to steam break through, the lower perforated intervals are isolated with production packers containing knock-out plugs. A correlatable selected upper interval in both wells is perforated and hydraulic fracturing is repeated. Cyclic steam-flooding and oil production are continued in the upper interval until steam break through occurs. Cyclic steam-flooding is ceased and production strings are directed through the knock-out plugs into the lower interval.

Abstract: A method for controlling the production of formation fines during the production of heavy oils from a sandstone formation. Hydraulic fracturing is conducted in an interval of the formation using a viscous gel fracturing fluid having a proppant therein. The proppant is sized based on the particle size distribution of the formation fines so as to restrict formation fines movement into the propped fracture. Thereafter, intermittent steam injection is conducted in the formation's productive interval. Hydrocarbon production from the formation is controlled so as to allow formation fines build-up on the fracture face thereby improving the filtration of fines from the heavy oil. After removing a desired amount of hydrocarbonaceous fluids from this productive interval, it is mechanically isolated. Thereafter, the steps are repeated in another productive interval.

Abstract: A method to enhance steam flooding where at least two horizontal wellbores are utilized. Carbon dioxide is injected into a lower perforated horizontal wellbore. Once sufficient carbon dioxide has been injected into the formation, steam is injected through the lower horizontal wellbore. The steam displaces the carbon dioxide into the formation where it contacts and mixes with hydrocarbonaceous fluids. Steam causes the carbon dioxide to expand, thereby providing for a better sweep of the formation. Steam injection is ceased and liquid carbon dioxide injection again is commenced. Afterwards, steam is injected again into the formation. This sequence is continued until it becomes uneconomical to produce hydrocarbonaceous fluids from an upper horizontal wellbore. Hydrocarbon displacement efficiencies are enhanced when hydrocarbons are produced into the upper horizontal wellbore due to viscosity and density differences.