Abstract: A well screen for use in gravel packing completions which produces a good distribution of gravel over the entire completion interval. The screen is comprised of a base pipe and an outer surface (e.g. wire wrap). A plurality of flow paths (e.g. shunt tubes) are positioned in the annulus which is formed between the base pipe and the outer surface of the screen, thereby providing the necessary alternate flowpaths for the slurry without substantially increasing the overall, effective outside diameter of the screen.

Abstract: A cement 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 method for fracturing and propping a thick and/or non-homogeneous fracture interval of a subterranean formation which is traversed by a wellbore. A workstring is lowered into the wellbore and a fracturing fluid is flowed into one end of the fracture interval annulus (i.e. that portion of the well annulus which lies adjacent the fracture interval) to initiate a fracture. The flow of fracturing fluid is ceased and a slurry containing proppants is flowed into said one end of the fracture interval annulus. During flow of fracturing fluid and slurry into said one end of the annulus, both are delivered through alternate flowpaths to different levels within said fracture interval. Alternate slugs of fracturing fluid and slurry is continued through the same end of the annulus until all of the levels or zones within the fracture interval have been fractured and propped and in some instances, also gravel-packed.

Abstract: A well tool for delivering fluid (e.g. sand or gravel slurry) to different levels within a wellbore which is comprised of a delivery conduit which, in turn, has a plurality of exit ports spaced along its length. Each exit port has an exit tube connected thereto. Each exit tube includes a portion whose length lies substantially parallel to the longitudinal axis of the delivery conduit which permits larger exit ports to be used which, in turn, substantially reduces the likelihood of an exit port becoming blocked prior to completion of a well operation. Also, where at least a portion of an exit tube is inside the delivery conduit, the concentration of the sand flowing through the exit tube will be substantially the same as the original concentration in the slurry since sand particles will not tend to by-pass an exit port and remain in the slurry. This prevents the premature dehydration of the slurry and the resulting buildup of sand within the delivery conduit which is normally associated therewith.

Abstract: A method for fracturing and propping a thick and/or non-homogeneous fracture interval of a subterranean formation which is traversed by a wellbore. A workstring is lowered into the wellbore and a fracturing fluid is flowed into either or both ends of the fracture interval annulus (i.e. that portion of the well annulus which lies adjacent the fracture interval) to initiate a fracture. The flow of fracturing fluid is continued into one end of the annulus while a slurry containing proppants is flowed into the other end of the fracture interval annulus. During flow of fracturing fluid and slurry into the annulus, slurry and/or fracturing fluid is also delivered through alternate flowpaths to different levels within said fracture interval. This is continued until all of the levels or zones of the fracture interval have been fractured and propped.

Abstract: A method of completing a well which includes the installion of a gravel pack completion adjacent a formation in the well. A fluid-loss agent is flowed into the well to form a barrier to flow into and/out of the formation prior to the installation of the gravel pack. A screen is then lowered into the well and is positioned adjacent the formation. A gravel slurry which includes a removal agent is flowed into the well to deposit gravel. The removal agent contacts and dissolves or disintegrates the flow barrier to thereby open flow to the formation during the placement of the gravel.

Abstract: A method and apparatus for gravel packing wherein a gravel slurry is distributed to different points of a wellbore annulus from a internal passage within the apparatus thereby protecting the passage from damage during operation. The apparatus is comprised of a plurality of gravel screen units which are connected together at the lower end of a workstring. Each gravelscreen unit is comprised of a gravel screen and a valve-outlet assembly which, in turn, is comprised of a collar having an outlet and a valve for opening and closing the outlet. A washpipe is positioned within the workstring and provides a passage for delivering the slurry internally to the outlets in each of the valve-outlet assemblies. The valves are closed when the washpipe is removed.

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 sand consolidation agent is introduced into the perforations before the channels can be filled with formation fines. The consolidation agent remains in the perforations for a time sufficient to form a 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, a substantially fines free hydrocarbonaceous fluid is produced from the wellbore.

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 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 method for producing substantially sand or fines free hydrocarbonaceous fluids from a wellbore which is initially gravel packed. Thereafter, an acid is directed into the wellbore so as to dissolve formation fines in channels contained in perforations communicating with a productive interval of the formation. The acid is of a strength sufficient to dissolve said fines. After the fines are dissolved, a sand consolidation agent is introduced into the perforations before the channels can be filled with formation fines. The consolidation agent remains in the perforations for a time sufficient to form a cement in situ which cement has permeability retentive characteristics. The cement forms pores of a size sufficient to exclude formation fines from the wellbore.

Abstract: A method and apparatus for gravel packing an interval of a wellbore wherein a permeable screen having a means for restricting fluid flow from the annulus into the upper portions of the screen is positioned adjacent the wellbore interval. The flow-restrictive means may be comprised of any material which remains substantially solid during circulation of the gravel slurry but preferably is a material that can be removed, e.g. by melting or dissolving, after the gravel has been placed. Examples of such material are (1) blends of waxes; (2) eutectic compounds formed by combining organic compounds; (3) salts; and (4) asphaltenes which are soluble in crude oil. The flow-restrictive means also may be formed of a perforated metal sleeve which is dissolvable by acid.

Abstract: A method and apparatus for treating multiple strata in a single operation from a single wellbore which penetrates a treatment interval which, in turn, includes a plurality of strata which, in turn, have different permeabilities. A treating fluid (e.g. consolidating agent, acid, etc.) is delivered directly to different levels within a section of the wellbore adjacent the interval to be treated through a plurality of alternate paths which, in turn, lie substantially adjacent to the strata to be treated.

Abstract: A method for producing multiple fractures by a single operation from a single wellbore which penetrates a fracture interval which, in turn, includes a plurality of zones which break-down under different fracturing pressures. Fracturing fluid is delivered from a workstring directly to different levels within a section of the wellbore which lies adjacent the fracture interval through a plurality of alternate paths which, in turn, lie substantially adjacent to the zones to be fractured.

Abstract: Apparatus for gravel packing a wellbore interval having shunt means (i.e. conduits) on the external surface of a sand screen which can selectively deliver a gravel slurry to different levels of the interval during operation. The shunt means is comprised of a variety of differently configured, perforated conduits and/or arrangements of these conduits.

Abstract: A sand screen is positioned in a well adjacent an oil or gas reservoir to be produced. At least one conduit is in juxtaposition with the sand screen and has passageways at selected intervals to establish fluid communication between the conduit and the annulus of the well surrounding the sand screen. A gravel packing slurry is injected down the well to form a gravel pack in the annulus. Actuatable devices associated with the conduit passageways control fluid flow between the conduit and annulus so that if the gravel portion of the slurry forms a bridge in the annulus, thereby blocking slurry flow through the annulus, the slurry will be diverted from the annulus into the conduit through one or more of the passageways in the conduit above the bridge, downward through the conduit and out through one or more passageways in the conduit into the annulus below the bridge to continue the forming of the gravel pack in the annulus.

Abstract: A method for recovery of oil from a subterranean, viscous oil-containing formation penetrated by one or more wells each of which is provided with at least one separate flow paths, the first flow path in fluid communication with the bottom of the formation from adjacent or below the formation and the second flow path in fluid communication with substantially the full vertical thickness of the formation. Steam is injected into the formation via the second flow path and fluids including oils are recovered from adjacent or below the bottom of the formation via the first flow path at a predetermined rate which is substantially less than the injection rate of steam so as to increase the formation pressure to a desired level. Formation pressure is maintained at the desired level while continuing injection of steam and production of fluids including oil until the fluids recovered contain an unfavorable amount of water.

Abstract: A process for minimizing well recompletions in a hydrocarbonaceous fluid containing formation having an upper productive interval temperature in excess of 300.degree. F. In this process, a temperature activated gellable composition is injected into a producer well in the productive interval after cooling said well to a temperature of about 300.degree. F. to about 450.degree. F. Once in the productive interval, the formation heats the gellable composition to a temperature sufficient to cause the composition to form a solid gel thus closing pores in the upper productive interval. Thereafter, ungelled composition is either diluted or removed from cooler areas of the formation so as to prevent forming a solid gel therein. Afterwards, a steam-flooding or a steam stimulation oil recovery operation is conducted to remove hydrocarbonaceous fluids from a lower productive interval without recompleting said lower interval.

Abstract: A method for gravel packing a well penetrating an unconsolidated or poorly consolidated subterranean oil or gas reservoir. The well employs a borehole casing with perforation tunnels for fluid communication between the borehole casing and a substantial portion of the reservoir. A sand screen is located inside the well casing and in juxtaposition with the perforation tunnels forming an annulus between the borehole casing and the sand screen. One or more conduits are positioned coaxially adjacent the exterior of the sand screen with openings to provide fluid communication between the conduit and a substantial portion of the annulus between the borehole casing and the sand screen. A slurry of gravel is injected down through the annulus between the borehole casing and the sand screen until the annulus is filled with gravel.

Abstract: A process for improved acidizing in carbonate formations, where controlled pulse fracturing (CPF) is utilized in combination with a retarded acid and a solidifiable gel. The solidifiable gel forms a solid formation gel in a zone of greater permeability and a gel plug in the wellbore. Said gel is formed from a melamine formaldehyde resin and a cross-linkable polymer. An inhibited acid is placed in an interval of said formation having lessened permeability. The retarded acid comprises hydrochloric, formic, acetic acid or mixtures thereof which is placed in a wellbore adjacent the area to be treated. Said acid can contain retarders and corrosion inhibitors sufficient to make said acid stable in the wellbore. At least one CPF device is placed in said acid near the interval to be treated. Upon detonation of said device, acid is forced into the interval of lessened permeability, thereby enhancing the acidizing treatmemt.