Abstract: A process is disclosed for treating an underground formation, which process comprises: (a) introducing into the underground formation a micellar dispersion comprising water, one or more organic acid precursors, one or more surfactants and, optionally, one or more salts, co-surfactants and/or organic liquids that are not organic acid precursors; and (b) allowing (i) the micellar dispersion to solubilize hydrocarbons, emulsions or water blocks present in the underground formation, and (ii) at least a portion of the organic acid precursor to hydrolyze in-situ to produce sufficient organic acid to substantively dissolve acid soluble material present in or adjacent to filter cakes or other damage in the underground formation.

Abstract: In one embodiment, the present invention provides a drilling fluid composition that comprises a surfactant-free emulsion comprising an oleaginous fluid, a fluid that is at least partially immiscible with the oleaginous fluid, and a non-surfactant polymeric emulsifier. In another embodiment, the present invention provides a method of treating a subterranean formation comprising providing a treatment fluid that comprises a surfactant-free emulsion, the surfactant-free emulsion comprising an oleaginous fluid, a fluid that is at least partially immiscible with the oleaginous fluid, and a non-surfactant polymeric emulsifier; and treating the subterranean formation.

Abstract: A well treatment fluid containing borated galactomannan may be used to isolate a productive zone in a well having multiple productive zones. The fluid is particularly useful in treatment of wells containing a mechanical zonal isolation system in the productive zone of interest. The fluid is pumped into the well in a substantially non-hydrated form. The well treatment fluid is therefore highly effective in preferentially sealing or blocking productive zones in the formation since delayed hydration of the fluid may be controlled for up to several hours.

Abstract: The present invention is directed to an improved thermoplastic material-coated particulate composition useful for hydraulic fracturing treatments, gravel packing for sand control or other well formation treatments and especially the related methods of its use and is particularly directed to using a thermoplastic material as part of a particulate composition in a method for enhancing the stabilization of and reducing particulate flowback and fines transport in a well formation.

Abstract: A microemulsion system is disclosed which comprises a solvent subsystem, a co-solvent subsystem and a surfactant subsystem comprises at least one monoalkyl branched propoxy sulfate anionic surfactant, where the microemulsion system are useful in drilling, producing, remediation, and fracturing application to reduce water blocks and water blocking in formation of a producing formation.

Abstract: Improved treatment fluids and methods for use in subterranean operations including the treatment of low permeability shale formations. In one embodiment the methods comprise: providing a treatment fluid comprising an aqueous base fluid and a controlled wetting system that comprises: a water soluble polymer having a charge, a surfactant having an opposite charge, and a compatibilizer; and introducing the treatment fluid into a subterranean formation.

Abstract: In a method of hydraulically fracturing a hydrocarbon-bearing subterranean formation, a proppant stage is introduced into the fracture which contains a gaseous fluid and an ultra lightweight proppant suspended in a viscosified aqueous fluid. The gaseous fluid of the proppant stage contains at least about 90 volume percent of the combination of gaseous fluid and aqueous fluid. A pad fluid may first be introduced into the formation, the pad fluid containing a gaseous fluid and, optionally, an aqueous fluid. The gaseous fluid of the pad fluid mixture typically contains at least 70 volume percent of the mixture.

Abstract: A system includes a hydraulic fracturing fluid including a polymeric constituent and an additive having particles including poly-vinyl acetate in an amount sufficient to control fluid loss. The system includes a formation of interest having a downhole temperature, and the particles including poly-vinyl acetate have a size and/or shape such that the poly-vinyl acetate hydrolyses at the downhole temperature. The particles may have a size and/or shape such that the particles are deformable at the downhole temperature. The poly-vinyl acetate in the particles may be a part of the particle substrate, a coating on the particles, and/or the entire particle may be poly-vinyl acetate. The poly-vinyl acetate may be included in any portion of the hydraulic fracturing fluid, or only the portion of the hydraulic fracturing fluid that is not proppant laden.

Abstract: The present invention relates to methods and compositions for carrier fluids comprising water-absorbent fibers. One embodiment of the present invention provides a method of treating a portion of a subterranean formation, comprising providing a slurry wherein the slurry comprises a servicing fluid, particulates, and a degradable, water-absorbent material wherein the degradable, water-absorbent material acts to help keep the particulates from settling out of the slurry; and, introducing the slurry into the portion of the subterranean formation. Another embodiment of the present invention provides a slurry suitable for use in subterranean operations comprising a servicing fluid, particulates, and a degradable, water-absorbent material wherein the degradable, water-absorbent material acts to help keep the particulates from settling out of the slurry.

Abstract: Gelled liquid hydrocarbons and methods for gelling hydrocarbons and treating subterranean wellbores employ a phosphorus compound of the formula: wherein, X is a straight chained alkyl or alkoxy group having 5 to 18 carbon atoms in combination with a polyvalent metal source.

Abstract: Apparatus and methods of reducing the viscosity of a gelled fluid is provided. In one embodiment, a viscosity reducing microbe is disposed in a capsule and added to the gelled fluid. The gelled fluid may include a thickening agent adapted to increase its viscosity. Upon release from the capsule, the microbe begins to digest the thickening agent in the gelled fluid and/or releases enzymes that that breakdown the thickening agent.

Abstract: A method is provided for treating at least a portion of a well. The method includes the steps of: (a) simultaneously introducing into a mixer at least: (i) a first stream comprising water; (ii) a second stream comprising a dry, hydratable, viscosity-increasing agent for water, wherein the second stream is substantially free of water; and (iii) a third stream comprising a non-hydratable, insoluble particulate; wherein at least the first and second streams are not mixed prior to being introduced into the mixer; (b) mixing the first, second, and third streams in the mixer to form a pumpable mixture, wherein: (i) the mixer creates at least a sufficiently-high shear rate to disperse the viscosity-increasing agent and the insoluble particulate in the pumpable mixture; and (ii) the pumpable mixture has or is capable of developing a substantially-higher viscosity than the viscosity of the first stream; and (c) introducing a treatment fluid comprising the pumpable mixture into a wellbore.

Abstract: A composition for treating a portion of a wellbore or a portion of a subterranean formation is provided, the composition comprising: (a) water; (b) a source of hydrogen peroxide, and (c) an activator for the source of hydrogen peroxide; wherein the pH of the composition is adjusted to be within an appropriate range for the type of activator. A method for treating a portion of a wellbore or a portion of a subterranean formation, the method comprising the steps of: forming or providing a composition comprising: (a) water; (b) a source of hydrogen peroxide, and (c) an activator for the source of hydrogen peroxide; wherein the pH of the composition is adjusted within an appropriate range for the type of activator; and introducing the composition through a wellbore to treat a portion of a wellbore or a portion of a subterranean formation. The activator can be a water-soluble alkanoyl-donor compound or a chelated transition metal. Preferably, the composition further comprises an iron chelating agent.

Abstract: A method and composition for treating a subterranean formation with a fluid, including forming a fluid including a particulate and an organosilane with the chemical formula RnSiX4-n, wherein n is equal to 1, 2, or 3, R is an organic functional group, and X is a halogen, alkoxy, or acetoxy group, introducing the fluid into a subterranean formation with exposed surfaces, and modifying the wettability of a surface of the particulate or subterranean formation or both. A method and composition for treating a subterranean formation with a fluid including forming a fluid comprising a particulate and an organosilane, introducing the fluid into a subterranean formation with exposed surfaces, and modifying the wettability of the proppant or surfaces or both, wherein the wettability modification degrades.

Abstract: A composition for treating a portion of a wellbore or a portion of a subterranean formation is provided, the composition comprising: (a) water; (b) a source of hydrogen peroxide, and (c) an activator for the source of hydrogen peroxide; wherein the pH of the composition is adjusted to be within an appropriate range for the type of activator. A method for treating a portion of a wellbore or a portion of a subterranean formation, the method comprising the steps of: forming or providing a composition comprising: (a) water; (b) a source of hydrogen peroxide, and (c) an activator for the source of hydrogen peroxide; wherein the pH of the composition is adjusted within an appropriate range for the type of activator; and introducing the composition through a wellbore to treat a portion of a wellbore or a portion of a subterranean formation. The activator can be a water-soluble alkanoyl-donor compound or a chelated transition metal. Preferably, the composition further comprises an iron chelating agent.

Abstract: A method includes identifying application parameter(s) including a subterranean formation temperature, determining a breaker particle size in response to the application parameter(s), providing a treatment fluid including a carrier fluid and a granular breaker sized according to the breaker particle size, and treating the subterranean formation with the treatment fluid. The granular breaker is a metallic peroxide which may be an alkaline peroxide and/or zinc peroxide. The application parameter(s) may further include a flowback wait time, a composition of the metallic peroxide, a gel loading of the carrier fluid, and a permeability of the subterranean formation. The breaker particle size may include a breaker large particle size that is not greater than 25% larger than a breaker small particle size. At least 90% of the breaker particles may be sized between the breaker small particle size and the breaker large particle size.

Abstract: In a method of hydraulically fracturing a hydrocarbon-bearing subterranean formation, a proppant stage is introduced into the fracture which contains a gaseous fluid and an ultra lightweight proppant suspended in a viscosified aqueous fluid. The gaseous fluid of the proppant stage contains at least about 90 volume percent of the combination of gaseous fluid and aqueous fluid. A pad fluid may first be introduced into the formation, the pad fluid containing a gaseous fluid and, optionally, an aqueous fluid. The gaseous fluid of the pad fluid mixture typically contains at least 70 volume percent of the mixture.

Abstract: A method of treating a subterranean formation penetrated by a wellbore of a well having iron-containing components is carried out by introducing a treatment fluid into the wellbore of the well. The treatment fluid is formed from an aqueous solution, a mineral acid, a viscoelastic surfactant gelling agent and corrosion inhibitor system containing at least one of an alkyl, alkenyl, alicyclic or aromatic substituted aliphatic ketone and aliphatic or aromatic aldehyde. The treatment fluid is substantially free of any formic acid or precursor formic acid. In certain embodiments, the corrosion inhibitor system comprises a mixture of at least one of an alkenyl phenone or ?,?-unsaturated aldehyde, an unsaturated ketone or unsaturated aldehyde other than the alkenyl phenone and ?,?-unsaturated aldehyde, a dispersing agent, an extender and an alcohol solvent. A corrosion inhibitor intensifier may also be used in certain embodiments, which may include a mixture of cuprous iodide and cuprous chloride.

Abstract: Subterranean treatment fluids that exhibit enhanced particulate transport or suspension capabilities, and associated methods of use in certain subterranean treatments are provided. In one embodiment, the methods comprise: providing a linear gelled fluid that comprises an aqueous base fluid, a plurality of particulates, and a linear particulate transport enhancing additive, the linear gelled fluid having a certain yield stress, crossover frequency, and/or particulate settling time; introducing the linear gelled fluid into the subterranean formation; and using the linear gelled fluid to create or enhance at least one fracture in at least a portion of the subterranean formation.

Abstract: A microemulsion system is disclosed which comprises a solvent subsystem, a co-solvent subsystem and a surfactant subsystem comprises at least one monoalkyl branched propoxy sulfate anionic surfactant, where the microemulsion system are useful in drilling, producing, remediation, and fracturing application to reduce water blocks and water blocking in formation of a producing formation.

Abstract: A method includes hydraulically fracturing a subterranean formation with a first treatment fluid and allowing the hydraulic fracture to close. The method includes preparing a second treatment fluid having a damage removal agent including carbon dioxide. The second treatment fluid further includes a proppant pack damage removal agent including an oxidizer, a radical initiator, an acid, a solvent, and/or other damage removal agents. The method further includes injecting the second treatment fluid into the subterranean formation at a downhole pressure below a fracturing pressure for the subterranean formation. The method includes holding pressure on the formation while the second treatment fluid enhances formation and proppant pack permeability, and flowing the second treatment fluid back to the surface.

Abstract: A method and apparatus for enhanced recovery of petroleum fluids from the subsurface by injection of a steam and hydrocarbon vaporized solvent in contact with the oil sand formation and the heavy oil and bitumen in situ. Multiple propped hydraulic fractures are constructed from the well bore into the oil sand formation and filled with a highly permeable proppant. Steam, a hydrocarbon solvent, and a non-condensing diluent gas are injected into the propped fractures, and flows upwards and outwards to contact and heat the in situ bitumen, which softens and flows by gravity to the well bore, and is pumped to the surface where the solvent can be recycled for further injection.

Abstract: Methods and compositions that include a method comprising: providing a treatment fluid comprising at least a plurality of degradable diverting agents that comprise at least one degradable material selected from the group consisting of a fatty alcohol, a fatty acid salt, a fatty ester, a proteinous material, and a combination thereof; and introducing the treatment fluid into a subterranean formation during a subterranean operation via a well bore.

Abstract: A viscoelastic composition containing an effective amount of at least one cationic carbohydrate ether having one or more cationic fragments and one or more carbohydrate fragments connected through one or more linker fragments for controlling the viscoelasticity of the composition, wherein at least some carbohydrate fragments are connected to the linker fragments through ether bonds. The viscoelastic composition of the present technology may be used to alter fluid rheology and impart both viscous and elastic properties to the treated fluids. Applications of the viscoelastic composition of the present technology include, but are not limited to, oil field fluids such as, for example, well bore treatment fluids.

Abstract: Methods and compositions useful for subterranean formation treatments, such as hydraulic fracturing treatments and sand control that include porous materials. Such porous materials may be selectively configured porous material particles manufactured and/or treated with selected glazing materials, coating materials and/or penetrating materials to have desired strength and/or apparent density to fit particular downhole conditions for well treating such as hydraulic fracturing treatments and sand control treatments. Porous materials may also be employed in selected combinations to optimize fracture or sand control performance, and/or may be employed as relatively lightweight materials in liquid carbon dioxide-based well treatment systems.

Abstract: Methods and compositions useful for subterranean formation treatments, such as hydraulic fracturing treatments and sand control that include porous materials. Such porous materials may be selectively configured porous material particles manufactured and/or treated with selected glazing materials, coating materials and/or penetrating materials to have desired strength and/or apparent density to fit particular downhole conditions for well treating such as hydraulic fracturing treatments and sand control treatments. Porous materials may also be employed in selected combinations to optimize fracture or sand control performance, and/or may be employed as relatively lightweight materials in liquid carbon dioxide-based well treatment systems.

Abstract: A method for breaking a fracturing fluid includes identifying application parameter(s) including a subterranean formation temperature, and determining an acid precursor concentration in response to the application parameter(s). The method further includes providing a treatment fluid including a carrier fluid, a metallic peroxide breaker, and an amount of an acid precursor according to the acid precursor concentration, and treating the subterranean formation with the treatment fluid. The application parameter(s) may further include a flowback wait time, a composition of the metallic peroxide breaker, a gel loading of the carrier fluid, and/or a permeability of the subterranean formation. The metallic peroxide breaker may include an alkaline peroxide and/or a zinc peroxide. The acid precursor may include polylactic acid and/or polyglycolic acid.

Abstract: A composition and method for improving the fluid efficiency of many oilfield treatments is given. The composition is a solid additive, in a viscosified fluid, in a size range small enough that it enters formation pores; it optionally bridges there to form an internal filter cake, and then decomposes to provide a breaker for the viscosifying system for the fluid. Examples of suitable additives include waxes, polyesters, polycarbonates, polyacetals, polymelamines, polyvinyl chlorides, and polyvinyl acetates. Degradation of the additive may be accelerated or delayed.

Abstract: Methods and apparatus of embodiments of the invention relate to a system for treating a subterranean formation including mixing equipment to form a fluid comprising sodium hypochlorite and sodium diacetate; and pumps and a tubular to introduce the fluid into the subterranean formation, wherein a surface of the subterranean formation contains at least 15 percent less microorganisms than if no sodium hypochlorite were in the fluid. Methods and apparatus of embodiments of the invention relate to a method of producing a petroleum product from a wellbore including using a well treatment system comprising mixing equipment, pumps, and a tubular, forming a fluid comprising sodium hypochlorite and sodium diacetate; and introducing the fluid to the well treatment system to achieve a reduced population of microorganisms in the system.

Abstract: The invention relates to the area of oil-and-gas production, based on hydraulic fracturing method and can be used for enhancement of the well production. The method for enhancement of fracture conductivity comprises the chemical treatment of the fracture surface and the space between the proppant pillars over the protective mask formed by material precipitated out from the said proppant pillar.

Abstract: Many methods and compositions are provided. One of the methods provided comprises the steps of: providing an aqueous treatment fluid that comprises a polysaccharide and a dual functional component, the aqueous treatment fluid having a first viscosity; allowing the dual functional component to interact with the polysaccharide such that the viscosity of the aqueous treatment fluid increases to a second viscosity, the second viscosity being greater than the first viscosity; placing the aqueous treatment fluid into a subterranean formation; and allowing the dual functional component to interact with the polysaccharide so as to reduce the second viscosity of the aqueous treatment fluid to a third viscosity, the third viscosity being less than the second viscosity. An example of a composition is a viscosified treatment fluid for treating subterranean formations comprising: an aqueous base fluid and an apparent cross linked reaction product of a polysaccharide and a dual functional component.

Abstract: The present invention relates to an acidic aqueous solution containing a chelating agent and an acid, wherein the chelating agent is glutamic acid N,N-diacetic acid (GLDA) or a salt thereof and wherein the amount of GLDA or the salt thereof is at least 10 wt %, based on the weight of the aqueous solution, and to the use thereof as an oilfield chemical, in descaling processes, or in processes in which highly concentrated aqueous acids are used, such as cleaning processes or plating processes.

Abstract: A method is provided for in-situ production of oil shale wherein a network of fractures is formed by injecting liquified gases into at least one substantially horizontally disposed fracturing borehole. Heat is thereafter applied to liquify the kerogen so that oil shale oil and/or gases can be recovered from the fractured formations.

Abstract: Methods are provided that include a method comprising providing a viscosified treatment fluid comprising a base fluid and a gelling agent that comprises a clarified xanthan; and placing the viscosified treatment fluid into at least a portion of a subterranean formation. In some embodiments, the method comprises placing the viscosified treatment fluid into at least a portion of a subterranean formation at a pressure sufficient to create or enhance at least one fracture in the subterranean formation. In some embodiments, the viscosified treatment fluid may also comprise a plurality of particulates. In some embodiments, the viscosified treatment fluids may be placed into at least a portion of a pipeline. Additional methods are also provided.

Abstract: A method and apparatus for processing a subterranean formation comprising stimulating and fracturing a subterranean formation, and drilling the subterranean formation wherein the drilling and fracturing occurs without removing equipment for drilling from the formation. A method and apparatus for drilling and fracturing a subterranean formation, comprising a drill string assembly and a hydraulic fracturing system, wherein the drill string and fracturing system are in communication with a wellbore and wherein the drill string and a fracture formed by the hydraulic fracturing system are less than about 1000 feet apart. A method and apparatus for processing a subterranean formation comprising fracturing a subterranean formation using a hydraulic fracturing system and drilling the subterranean formation using a drill string assembly wherein the drilling and fracturing occurs without removing the drill string from the formation, and wherein the fracturing occurs via ports in the drill string assembly.

Abstract: Provided herein are methods and compositions for generating acids for use downhole, for example, to break fluid-loss control pills. The delayed-release acid breakers of the present invention comprise orthoesters and/or poly(orthoesters).

Abstract: A system includes a wellbore in fluid communication with a formation of interest and a fracturing slurry include a carrier fluid with a low amount of a viscosifier, an amount of proppant including a first average particle size between about 200 and 2000 ?m, an amount particulates including a second average particle size between about three and ten times smaller than the first average particle size, and a third amount of particulates having a third average particle size smaller than the second average particle size. A sum of all of the particulates in the fracturing slurry exceed about 16 pounds per gallon of the carrier fluid. They system further includes a pumping device that creates a propped fracture in the formation of interest with the fracturing slurry, and a removal agent that removes the second amount of particulates and/or the third amount of particulates from the propped fracture.

Abstract: Methods and systems are disclosed for well completion and/or production, where an aggregating, agglomerating or conglomerating composition is injected into a producible formation, zone or interval thereof to alter an aggregation or zeta potential of formation surfaces and particulate to increase a maximum sand free production rate.

Abstract: A method for well treatment by forming a temporary plug in a fracture, a perforation, a wellbore, or more than one of these locations, in a well penetrating a subterranean formation is provided, in which the method of well treatment includes: injecting a slurry comprising a degradable material, allowing the degradable material to form a plug in a perforation, a fracture, or a wellbore in a well penetrating a formation; performing a downhole operation; and allowing the degradable material to degrade after a selected time such that the plug disappears.

Abstract: A method of producing natural gas from a heavy hydrocarbon-containing subterranean formation includes: placing a catalyst comprising a transition metal into the formation, injecting an anoxic stimulation gas into the formation, and collecting the natural gas generated in the formation. The method may be performed outside the context of a subterranean formation under controlled conditions. Thus, a method of producing natural gas from bitumen includes: providing an anoxic mixture of heavy hydrocarbons and a catalyst having a transition metal, adding an anoxic stimulation gas to the mixture, and heating the mixture in the presence of the stimulation gas.

Abstract: Friction reducing compositions for use in well treatment fluids generally include an aqueous fluid; a polymeric friction reducer; and 3,5-dimethyl-1,3,5-thiadiazinane-2-thione. It has been found that the combination of the polymeric friction reducer; and 3,5-dimethyl-1,3,5-thiadiazinane-2-thione unexpectedly and synergistically increases friction reduction and inversion behavior, where applicable. Also disclosed are methods for the fracturing of a subterranean hydrocarbon bearing formation to stimulate the production of the hydrocarbons by injecting the friction reducing composition.

Abstract: A method and apparatus for initiating and propagating a vertical hydraulic fracture in unconsolidated and weakly cemented sediments from a single bore hole to control the fracture initiation plane and propagation of the hydraulic fracture, enabling greater yield and recovery of petroleum fluids from the formation. An injection casing with multiple fracture initiation sections is inserted and grouted into a bore hole. A fracture fluid carrying a proppant is injected into the injection casing and opens the fracture initiation sections to dilate the formation in a direction orthogonal to the required fracture azimuth plane. Propagation of the fracture is controlled by supplying fracture fluid independent to the two opposing wings of the hydraulic fracture. The injection casing initiation section remains open after fracturing providing direct hydraulic connection between the production well bore, the permeable proppant filled fracture and the formation.

Abstract: Methods of improving shear recovery time of viscoelastic surfactant fluid systems are described, one method involving providing a viscoelastic surfactant fluid system comprising a major portion of a surfactant and a rheology enhancer in a concentration sufficient to shorten shear recovery time of the fluid system compared to shear recovery time of the fluid system absent the rheology enhancer, the rheology enhancer selected from aromatic sulfonates having a molecular weight of at least 500; and injecting the fluid system down a well. The rheology enhancer may be a lignosulfonate derived from wood pulping. Viscoelastic surfactant systems including the rheology enhancer are also described.

Abstract: A process for in situ production of shale oil comprises fracturing the target zone 10 of an shale oil formation using a two step approach. First, an initial set of fractures 18 is developed in the formation by using high pressure gas pulses. Second, a secondary set of fractures 28 extending and further fracturing the initial set of fractures 18 is created using a modified ANFO mix 22 wherein rubber particles acting as solid fuel are blended in with ammonium nitrate and fuel oil. The solid fuel enhances the fracturing characteristics of ANFO while minimizing its crushing and compacting tendencies. Hot high pour point oil is then injected into the formation and forced into the receptor well 16 where it is pumped to the surface. By circulating oil in the formation at carefully controlled temperatures, kerogen can be decomposed at the optimum rate to maximize the amount of oil recovered and yield high quality shale oil.

Abstract: The present invention provides a method of forming a viscosified treatment fluid comprising: providing a treatment fluid that comprises water and a gelling agent; contacting the treatment fluid with a boronic acid crosslinking agent so as to form a crosslinked gelling agent, wherein the boronic acid crosslinking agent comprises a compound having the formula: The present invention also provides methods of crosslinking gelling agent molecules, methods of treating a subterranean formation, methods of reusing viscosified treatment fluids, methods of fracturing subterranean formations, and methods of placing a gravel pack in subterranean formations. The present invention also provides boronic acid crosslinking agents and viscosified treatment fluids that comprise crosslinked gelling agents, the crosslinked gelling agent being formed from a reaction comprising a gelling agent and a boronic acid crosslinking agent.

Abstract: Acidic treatment fluids used in industrial and/or subterranean operations, and more particularly, acidic treatment fluids comprising clarified xanthan gelling agents, and methods of use in industrial and/or subterranean operations, are provided. In one embodiment, the methods comprise: providing an acidic treatment fluid that comprises an aqueous base fluid, an acid, and a gelling agent that comprises clarified xanthan; and introducing the acidic treatment fluid into a portion of a subterranean formation.

Abstract: Acidic treatment fluids used in industrial and/or subterranean operations, and more particularly, acidic treatment fluids comprising clarified xanthan gelling agents, and methods of use in industrial and/or subterranean operations, are provided. In one embodiment, the acidic treatment fluids comprise an aqueous base fluid, an acid, and a gelling agent comprising clarified xanthan.

Abstract: A method of treating a shale-containing subterranean formation penetrated by a wellbore is accomplished by forming a carbon dioxide treatment fluid having a viscosity of less than about 10 mPa-s at a shear rate of about 100 s?1. The carbon dioxide treatment fluid is introduced into the formation through the wellbore at a pressure above the fracture pressure of the formation. In certain embodiments, the treatment fluid may be comprised of from about 90% to 100% by weight carbon dioxide and may contain a proppant. A method of treating hydrocarbon-bearing, shale-containing subterranean formation penetrated by a wellbore may also be carried out by forming a carbon dioxide treatment fluid and introducing the carbon dioxide treatment fluid into the formation through the wellbore at a pressure above the fracture pressure of the formation. The formation being treated may have a permeability of less than 1 mD.

Abstract: Viscoelastic surfactant (VES) gelled aqueous fluids containing water, a VES, an internal breaker, a VES stabilizer, a fluid loss control agent and a viscosity enhancer are useful as treating fluids and particularly as fracturing fluids for subterranean formations. These VES-based fluids have faster and more complete clean-up than polymer-based fracturing fluids. The use of an internal breaker permits ready removal of the unique VES micelle based pseudo-filter cake with several advantages including reducing the typical VES loading and total fluid volume since more VES fluid stays within the fracture, generating a more optimum fracture geometry for enhanced reservoir productivity, and treating reservoirs with permeability above the present VES limit of approximately 400 md to at least 2000 md.

Abstract: Methods and compositions that include a method comprising providing a treatment fluid that comprises an aqueous base fluid, a biocide, a biocide enhancer, a friction reducer, and a compatibility aid, and introducing the treatment fluid into a subterranean formation. A composition provided includes a treatment fluid comprising an aqueous base fluid, a biocide, a biocide enhancer, a friction reducer, and a compatibility aid.