Abstract: Treatment fluids for and methods of treating subterranean formations are provided. In certain embodiments, a method is provided comprising providing a treatment fluid comprising a relative permeability modifier, a delayed filter cake breaker, and a carrier fluid, contacting at least a portion of a filter cake in a subterranean formation with the treatment fluid, and removing at least a portion of the filter cake.

Abstract: Disclosed are methods of treating subterranean formations with rapidly hydratable treatment fluids based upon heteropolysaccharides. In particular, the invention relates to treatment methods with fluids containing a heteropolysaccharide, aqueous medium, and an electrolyte, wherein the fluids may further include a gas component, a surfactant and/or an organoamino compound. The fluids exhibit good rheological properties at elevated temperatures, and unusually rapid hydration rates which allows utilizing such fluids without the need of hydration tanks.

Abstract: A method of insulating pipeline bundles used in recovering hydrocarbons from wells is disclosed. A polymeric substance, such as an orthophosphate ester, is injected into the annulus between a carrier pipe and the hydrocarbon conveying tubulars. A ferric salt, such as ferric sulphate, may be added as a gelling agent. The mixture results in a gel having a dynamic viscosity of greater than (1000) PaS. The gel insulates the inner hydrocarbon-conveying tubulars from the surrounding seawater thus helping to maintain the relatively high temperature therewithin. This in turn reduces the likelihood for chemicals, such as hydrates, to be precipitated out of the oil phase.

Abstract: The current disclosure describes a multifunctional fluid that addresses a new concept in the removal of filter cake. A composition is disclosed comprising: a carrier fluid, a surfactant, a fluorine source and an organic stabilizer able to minimize precipitation of fluorine The associated method to remove the filter cake is also described.

Abstract: An oilfield treatment method is given that uses fluids that contain surfactants used as foamers and/or viscosifiers such that the fluids pass the Alberta Energy and Utilities Board Directive 27 requirements for low toxicity to certain bioluminescent bacteria. Such fluids may be used in oilfield treatments, for example drilling and stimulation, near fresh water aquifers. The surfactants are certain non-ionic surfactants that are not aromatic, or certain amphoteric surfactants (that can be neutral), or certain zwitterionic surfactants, (in which both positive and negative charges are present in a single molecule so that the whole molecule is neutral).

Abstract: The present invention relates to well bore stabilization and, more particularly, to treatment fluids that may reduce the tendency of shales to swell and associated methods. In some embodiments, the present invention provides a method of stabilizing a subterranean formation that comprises a shale, the method comprising contacting the subterranean formation that comprises the shale with a treatment fluid, the treatment fluid comprising a base fluid, and a hydrophobically modified polymer. In other embodiments, the treatment fluids comprise a base fluid and a hydrophilically modified polymer. In yet other embodiments, the present invention provides shale-inhibiting components, treatment fluids, and methods of reducing the tendency of shale to swell when exposed to a treatment fluid.

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: A cross-linking composition comprises (a) an aqueous liquid, (b) a pH buffer, (c) a cross-linkable organic polymer, (d) a cross-linking agent which comprises an organic titanate, an organic zirconate, or combinations thereof, and (e) a delay agent which is a hydroxyalkylaminocarboxylic acid. The composition provides flexibility in rate of cross-linking and can be used over a wide range of pH. Further disclosed are methods to use the composition in oil field applications for hydraulic fracturing and plugging of permeable zones and leaks in subterranean formations.

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: Hydrocarbon fluid compositions comprising a liquid hydrocarbon, an aluminum soap, a hydrocarbon foaming agent and a gas. The fluids can be used in various oil field operations.

Abstract: Single phase microemulsions improve the removal of filter cakes formed during drilling with oil-based muds (OBMs). The single phase microemulsion removes oil and solids from the deposited filter cake. Optionally, an acid capable of solubilizing the filter cake bridging particles may also be used with the microemulsion. In one non-limiting embodiment the acid may be a polyamino carboxylic acid. Skin damage removal from internal and external filter cake deposition can be reduced. In another optional embodiment, the single phase microemulsion may contain a filtration control additive for delaying the filter cake removal, destruction or conversion.

Abstract: The present invention provides aqueous viscoelastic compositions comprising a cleavable surfactant and possibly also an electrolyte. The cleavable surfactants useful in the present invention comprise at least one weak chemical bond, which is capable of being broken under appropriate conditions, to produce oil soluble and water soluble products typically having no interfacial properties and surface activity compared with the original surfactant molecule. Further, the rheological properties of the aqueous viscolelastic composition are usually altered upon cleavage of the cleavable surfactant generally resulting in the elimination of the viscofying, viscoelastic and surfactant properties of the composition. Aqueous viscoelastic compositions in accordance with the present invention are suitable for use in oil-field applications, particularly for hydraulic fracturing of subterranean formations. Thus, the present invention also relates to a wellbore service fluid and a method of fracturing a subterranean formation.

Abstract: Of the many methods provided herein, one method of reducing the viscosity of a viscosified treatment fluid includes: providing a clean-up composition comprising a carboxylic acid; providing a chlorite-based breaker system; providing a viscosified treatment fluid; placing the viscosified treatment fluid in a subterranean formation via a well bore penetrating the subterranean formation; contacting the viscosified treatment fluid with the clean-up composition; contacting the viscosified treatment fluid with the chlorite-based breaker; and allowing the viscosity of the viscosified treatment fluid to reduce. Also provided herein are methods that include a method of reducing polymeric residue from a subterranean formation that includes: placing a clean-up composition and a chlorite-based breaker system in a subterranean formation in contact with an amount of polymeric residue; and allowing the amount of polymeric residue present in the formation to be reduced.

Abstract: Fluids viscosified with viscoelastic surfactants (VESs) may have their viscosities reduced (gels broken) by the direct or indirect action of a synergistic internal breaker composition that contains at least one first internal breaker that may be a mineral oil and a second breaker that may be an unsaturated fatty acid. The internal breakers may initially be dispersed oil droplets in an internal, discontinuous phase of the fluid. This combination of different types of internal breakers break the VES-gelled aqueous fluid faster than if one of the breaker types is used alone in an equivalent total amount.

Abstract: Fluids viscosified with viscoelastic surfactants (VESs) may have their viscosities reduced (gels broken) by the direct or indirect action of an internal breaker composition that contains at least one mineral oil, at least one polyalphaolefin oil, at least one saturated fatty acid and/or at least one unsaturated fatty acid. The internal breaker may initially be dispersed oil droplets in an internal, discontinuous phase of the fluid. In one non-limiting embodiment, the internal breaker, e.g. mineral oil, is added to the fluid after it has been substantially gelled. An oil-soluble surfactant is present to enhance or accelerate the reduction of viscosity of the gelled aqueous fluid.

Abstract: In one embodiment, the present invention provides a method of increasing the viscosity of a treatment fluid comprising the steps of: adding a networking agent to the treatment fluid, wherein the networking agent is represented by the formula: Y—X—[B(OR)2]n, wherein: Y is at least partially capable of forming a crosslink between a gelling agent molecule, a second networking agent, and/or a combination thereof; X is at least partially capable of preventing or inhibiting a reaction represented by the formula: ROH+R?B(OR)2?R?OH+B(OR)3; R and R? are a hydrogen, an alkyl group, an aryl group, or a combination thereof; and n is a positive integer greater than or equal to 1; allowing at least one crosslink to form between the networking agent and a gelling agent molecule, a second networking agent, and/or a combination thereof; and allowing the viscosity of the treatment fluid to increase.

Abstract: Single phase microemulsions improve the removal of filter cakes formed during drilling with invert emulsions. The single phase microemulsion removes oil and solids from the deposited filter cake. Optionally, an acid capable of solubilizing the filter cake bridging particles may also be used with the microemulsion. In one non-limiting embodiment the acid may be a polyamino carboxylic acid. Skin damage removal from internal and external filter cake deposition can be reduced.

Abstract: Presented herein are improved bridging agents comprising a degradable material, improved subterranean treatment fluids comprising such improved bridging agents, and methods of using such improved subterranean treatment fluids in subterranean formations. An example of a method presented is a method of drilling a well bore in a subterranean formation. Another example of a method presented is a method of forming a self-degrading filter cake in a subterranean formation. Another example of a method presented is a method of degrading a filter cake in a subterranean formation. An example of a composition of the present invention is a treatment fluid including a viscosifier, a fluid loss control additive, and a bridging agent comprising a degradable material. Another example of a composition presented is a bridging agent comprising a degradable material.

Abstract: A polyelectrolyte complex for the controlled release of an oil and gas field chemical selected from the group consisting of (a) a gel-forming or cross-linking agent, (b) a scale inhibitor, (c) a corrosion inhibitor, (d) an inhibitor of asphaltene or wax deposition, (e) a hydrogen sulfide scavenger, (f) a hydrate inhibitor, (g) a breaking agent, and a surfactant.

Abstract: A viscoelastic wellbore treatment fluid comprises an effective amount of an oligomeric surfactant for controlling the viscoelasticity of the fluid.

Abstract: A fluid for use in a subterranean formation penetrated by a wellbore, the fluid comprising: (a) water; (b) an orthoester; and (c) a surfactant comprising a tertiary alkyl amine ethoxylate generally represented by the following formula: (CH2—CH2—O)XH R—N< (CH2—CH2—O)YH wherein R is an alkyl group or aryl group, and wherein X and Y are each independently at least one. A method of fracturing a subterranean formation, comprising the step of forming a foamed fracturing fluid comprising water; an orthoester; a surfactant comprising a tertiary alkyl amine ethoxylate generally represented by the formula above; and a gas. The method also provides the step of introducing the foamed fracturing fluid into a subterranean formation at a pressure sufficient to create a fracture in the subterranean formation.

Abstract: Multi-component additive for incorporation into a drilling fluid, and a drilling fluid system comprising said multi-component additive. The additive preferably comprises three primary components: (1) a rate of penetration enhancer, namely one of a number of synthetic (non-toxic) ester-based or olefin-based oils as a carrier for other additives, such as surfactants; (2) a lubricant, namely one or more of a number of chlorinated waxes, chlorinated olefins, and plant based fatty acids; and (3) a clay inhibitor/stabilizer, such as a polyglycol. Preferably, the three components are pre-mixed in a single container, for ease in use in adding to a drilling fluid system. The additive may be incorporated into a drilling fluid system at a shore based facility, and the “liquid mud” transported to a drilling rig; or the additive may be brought to the drilling rig and incorporated into a drilling fluid system on site.

Abstract: The invention relates to a class of novel surfactants that have utility in the recovery and/or extraction of oil.

Abstract: The invention relates to a method for treating a reservoir rock, wherein the following stages are carried out: making a concentrated water-in-oil emulsion comprising: between 50% and 80% aqueous phase in which at least one treatment additive is dissolved and between 20% and 50% oil phase containing at least one polymeric surfactant, shearing the concentrated emulsion so as to obtain an emulsion having drops of substantially monodispersed size and essentially below 1 ?m, diluting the monodispersed emulsion with an oil phase so as to obtain an aqueous phase dispersed at a rate below 50%, and injecting the diluted emulsion into the reservoir rock.

Abstract: Degradable polylactic or polyhydroxyalkanoate polymers may be used to viscosify aqueous fluids for use in wells. Sand control screen or liner can be coated with a solid degradable polymer during placement in a well. Mechanical changes or flow changes in a well can be caused by solid degradable polymer that changes physical properties after it is placed in a well. Parts of devices or entire devices can be made of solid degradable polymer that converts to a fluid after selected times in an aqueous environment in a well.

Abstract: Methods and compositions including a method comprising: providing a treatment fluid comprising an aqueous fluid, a relative permeability modifier, and a chelating agent; introducing the treatment fluid into a well bore that penetrates a subterranean formation; and allowing at least a first portion of the treatment fluid to penetrate into a portion of the subterranean formation so as to substantially divert a second portion of the treatment fluid to another portion of the subterranean formation.

Abstract: Solid, particulate dicarboxylic acids may be fluid loss control agents and/or viscosifying agents for viscoelastic surfactant (VES) fluids in treatments such as well completion or stimulation in hydrocarbon recovery operations. The fluid loss control agents may include, but not be limited to, dodecanedioic acid, undecanedioic acid, decanedioic acid, azelaic acid, suberic acid, and mixtures thereof having a mesh size of from about 20 mesh to about 400 mesh (about 841 to about 38 microns). A mutual solvent or a blend of at least two alcohols subsequently added to the aqueous viscoelastic surfactant treating fluid will at least partially dissolve the solid, particulate dicarboxylic acid fluid loss control agents, and optionally also “break” or reduce the viscosity of the aqueous viscoelastic surfactant treating fluid.

Abstract: Non-aqueous carrier fluids containing nano-sized particles in high concentration are effective for zone isolation and flow control in water shutoff applications for subterranean formations. The nanoparticles interact with water and solidify it to inhibit its flow, but do not have the same effect on hydrocarbons and thus selectively assist the production of hydrocarbons while suppressing water. Suitable nanoparticles include alkaline earth metal oxides, alkaline earth metal hydroxides, alkali metal oxides, alkali metal hydroxides, transition metal oxides, transition metal hydroxides, post-transition metal oxides, post-transition metal hydroxides, piezoelectric crystals, and/or pyroelectric crystals.

Abstract: The present invention relates to methods and compositions for degrading filter cakes in subterranean formations, and more specifically, to improved methods and compositions for degrading filter cakes that comprise acid-soluble portions and polymeric portions.

Abstract: Hydraulic fracturing of wells by injecting a degradable polymer phase as a fracturing fluid is provided. Composition and degree of polymerization of the degradable polymer and the selection of additives may be varied to adjust the viscosity, degradation time and other properties of the fracturing fluid. Viscous degradable fluid or pellets of degradable polymer may be placed in a wellbore as an internal phase in a low viscosity carrier fluid. A polymer-continuous liquid phase may be formed at a selected location in the wellbore, usually near perforations, before the polymer phase is pressured into a formation to form a hydraulic fracture.

Abstract: An under-balanced drilling fluid additive is disclosed which reduces reactive shale and/or clay swelling during under-balanced drilling operations, where the additive includes an effective amount of a choline salt. A method for under-balanced drilling is also disclosed including the step of circulating a drilling fluid including an effective amount of a choline salt to reduce reactive shale and/or clay swelling during under-balanced drilling operations.

Abstract: Additives for use in treatment operations, and more particularly, additives that include chlorinated carbohydrates, are provided. An example of an additive is a well fluid additive for use in a subterranean formation that includes a chlorinated carbohydrate. Another example of an additive is a well fluid additive for use in a subterranean formation that includes a chlorinated carbohydrate and a tartaric acid.

Abstract: Piezoelectric crystal particles (which include pyroelectric crystal particles) enhance the viscosity of aqueous fluids that have increased viscosity due to the presence of viscoelastic surfactants (VESs). In one non-limiting theory, when the fluid containing the viscosity enhancers is heated and/or placed under pressure, the particles develop surface charges that associate, link, connect, or relate the VES micelles thereby increasing the viscosity of the fluid. The higher fluid viscosity is beneficial to crack the formation rock during a fracturing operation, reduce fluid leakoff, and carry high loading proppants to maintain the high conductivity of fractures.

Abstract: Hydraulic fracturing of wells by injecting a degradable polymer phase as a fracturing fluid is provided. Composition and degree of polymerization of the degradable polymer and the selection of additives may be varied to adjust the viscosity, degradation time and other properties of the fracturing fluid. Viscous degradable fluid or pellets of degradable polymer may be placed in a wellbore as an internal phase in a low viscosity carrier fluid. A polymer-continuous liquid phase may be formed at a selected location in the wellbore, usually near perforations, before the polymer phase is pressured into a formation to form a hydraulic fracture.

Abstract: The current invention provides a novel downhole maleic acid solution suitable for restoring fluid permeability to subterranean formations that were previously treated with chemical fluid loss control agents based on hydroxyethyl cellulose polymer. The current invention also provides methods for restoring fluid permeability to subterranean formations that have been treated with chemical fluid loss control agents based on hydroxyethyl cellulose polymer. The methods of the current invention contact the subterranean formation with downhole maleic acid solutions for a period of time sufficient to restore fluid permeability to the formation.

Abstract: Of the many compositions and methods provided herein, one method includes a method comprising: contacting tar resident in a well bore with a treatment fluid comprising a styrene-acrylate polymer; and allowing the styrene-acrylate polymer to interact with the tar to at least partially reduce the tendency of the tar to adhere to a surface. Another method provided herein includes a method for treating tar sand comprising: contacting the tar sand with a treatment fluid comprising an aqueous fluid and a styrene-acrylate polymer, the tar sand comprising tar and sand; and allowing the styrene-acrylate polymers to interact with the tar to at least partially separate the tar from the sand.

Abstract: Defoaming compositions for reducing the amount of gas present in a fluid such as a cement composition are provided. In an embodiment, a defoaming composition includes a carboxylic acid compound or an ester of a carboxylic acid compound; an alpha olefin compound; and an alcohol compound.

Abstract: An acidizing fluid for sandstone formations is provided, along with methods of acidizing a sandstone formation penetrated by a wellbore. The aqueous acid treatment is a mixture of an aqueous liquid, a fluoride source, and an effective amount of at least one homopolymer or copolymer of a polycarboxylic acid, salt thereof or derivative thereof, which is introduced into the wellbore, and allowed to acidize the formation and concurrently inhibit calcium fluoride formation and impart calcium tolerance to the fluid.

Abstract: The invention provides for the use of 1-alkyl-5-oxopyrrolidine-3-carboxylic esters, preparable by esterifying alcohols having from 1 to 100 hydroxyl groups with 1-alkyl-5-oxopyrrolidine-3-carboxylic acid, in amounts of from 0.01 to 2% by weight for preventing the formation of gas hydrates in aqueous phases which are in contact with a gaseous, liquid or solid organic phase.

Abstract: Methods and compositions relating to delayed tackifying compositions that comprise an aqueous tackifying agent and a delayed acid-releasing activator that may be used to stabilize particulates and reduce particulate migration within a subterranean formation.

Abstract: Methods comprising: providing a treatment fluid that comprises a base fluid and a least a plurality of coated particulates, the coated particulates having been treated with a surface modification agent and coated with a hydrolysable coating; placing the treatment fluid into a subterranean formation via a well bore. Also provided are methods comprising: treating a particulate with a surface modification agent; coating the particulate with a hydrolysable coating that has an initial degradation rate to produce a coated particulate; placing the particulate in a subterranean formation; and allowing the hydrolysable coating to degrade at a second degradation rate that is slower than its initial degradation rate.

Abstract: The invention discloses treatment and reuse of oilfield produced water. A method of inhibiting enzymes/bacteria in an aqueous medium for viscosification comprises contacting the aqueous medium with a denaturant and/or a bactericide and thereafter mixing a gelling agent in the aqueous medium. The viscosified fluid can be used as a well treating fluid for fracturing and other applications. A well treatment fluid comprises a metal denaturant and/or a bactericide and a gelling agent in an amount effective to viscosify the fluid. Also disclosed is oilfield produced water denatured with from 1 to 2000 ppm by weight of a zirconium compound.

Abstract: A process is described for replacing at least a portion of the liquid within the annular volume of a casing system within a wellbore with a second liquid. The second liquid is preselected to provide a measure of control of the pressure within the annular volume as the fluid within the volume is being heated.

Abstract: A composition useful in a well servicing fluid comprising a base fluid, comprising from 5-40 wt. % paraffins, from 5-40 wt. % olefins, from 5-20 wt. % naphthenes, from 5-20 wt. % esters, and from 2-10 wt. % oxygenates comprising primarily alcohols and ethers, the base fluid being useful as an additive alone or in conjunction with at least one other component typically used in well servicing fluids such as drilling fluids, workover fluids, packer fluids, etc.

Abstract: Treating compositions containing mutual solvents suitable for forming and maintaining single-phase aqueous fluid treating compositions containing very high concentrations of acids and/or chelating agents are described. Methods of use of these treating compositions for dissolving and removing scale and formation matrix material in oil-field treatments such as stimulation and remediation are given.

Abstract: Fluids viscosified with viscoelastic surfactants (VESs) may have their viscosities reduced (gels broken) by the direct or indirect action of a synergistic internal breaker composition that contains at least one first internal breaker that may be a mineral oil and a second breaker that may be an unsaturated fatty acid. The internal breakers may initially be dispersed oil droplets in an internal, discontinuous phase of the fluid. This combination of different types of internal breakers break the VES-gelled aqueous fluid faster than if one of the breaker types is used alone in an equivalent total amount.

Abstract: A method of delivering chemicals such as scale inhibitor into a wellbore producing fluids includes providing the chemicals, in a slow-release form, in a container located in the path of the production fluids so that the production fluids pass through the container. Preferably, the container is suspended in the production tubing and periodically retrieved from the well to be refilled.

Abstract: The invention describes a method for decreasing the viscosity of crude oils and residuum utilizing a combination of thermal and acidic treatment. Further, the invention describes a method for making a water-in-oil emulsion, or a solids-stabilized water-in-oil emulsion with a reduced viscosity. The emulsion can be used in enhanced oil recovery methods, including using the emulsion as a drive fluid to displace hydrocarbons in a subterranean formation, and using the emulsion as a barrier fluid for diverting flow of fluids in the formation.

Abstract: Many methods are provided herein including, in one embodiment, a method comprising: providing a fluid that comprises an acid, crosslinked oxidized xanthan, and optionally, a base fluid; placing the fluid in a well bore penetrating a subterranean formation; and allowing the fluid to acidize at least a portion of the formation or damage contained therein. In another embodiment, herein provided is a fluid for subterranean uses comprising an acid and crosslinked, oxidized xanthan.

Abstract: Surfactant systems are provided that, upon contact with an oil, can produce a Windsor Type III middle phase microemulsion at a total surfactant concentration of 1.5% to 1.0% or less based on the weight of water in the surfactant system, without the need for a cosolvent or linking molecule. The microemulsions can have a separation time less than about 2 hours and even less than about 15 minutes.