WO2018022693A1

WO2018022693A1 - Method for fracturing using a buoyant additive for proppant transport and suspension

Info

Publication number: WO2018022693A1
Application number: PCT/US2017/043853
Authority: WO
Inventors: Naima Bestaoui-Spurr; James B. Crews
Original assignee: Baker Hughes, A Ge Company, Llc
Priority date: 2016-07-27
Filing date: 2017-07-26
Publication date: 2018-02-01

Abstract

The transport and suspension of proppant in a fracturing fluid used to fracture a subterranean formation is improved by incorporating a buoyant additive into a carrier fluid that also comprises a proppant. The buoyant additive has a surface, in one non-limiting embodiment a hydrophobic surface or a superhydrophobic surface, and the buoyant additive is present in an amount effective to suspend at least a portion of the proppant in the fracturing fluid. The buoyant additive has had its surface modified with a surface modifying agent, which may include, but is not necessarily limited to, wax, silica, an organo silane, a siliconate, a silicate, a silsesquioxane, phosphonic acids, transition metal oxides, post-transition metal oxides, silicon, and combinations thereof.

Description

METHOD FOR FRACTURING USING A BUOYANT ADDITIVE

FOR PROPPANT TRANSPORT AND SUSPENSION

TECHNICAL FIELD

[1] The present invention relates to methods for fracturing subterranean formations penetrated by a well and treatment fluids therefore; and more particularly relates to methods for fracturing subterranean formations penetrated by a well and treatment fluids therefore, which provide proppant transport for placement and suspension within a fracture.

BACKGROUND

[2] Hydraulic fracturing increases the flow of desirable fluids such as oil and gas from a subterranean formation and involves placing a fracturing fluid into a subterranean formation or zone at a rate and pressure sufficient to impart a stress in the formation or zone with attendant creation of a fracture in the formation or zone.

[3] Beyond creating the fracture, the fracturing fluid also transports a proppant into the fracture. The proppant keeps the fracture open after release of the exerted pressure. Further, the proppant establishes conductive means in which the formation fluids flow to the borehole. Since the proppant provides a higher conductivity than the surrounding rock, the fracture has greater potential for production of hydrocarbons.

[4] However, sometimes the viscosity of some fracturing fluids breaks before the fracture closes, and the proppant separates from the fracturing fluid. In this situation, the proppants settles down by gravity and concentrate at the bottom of the fracture, and thus the geometry of the fracture and well productivity is impaired. Additionally, fractures are typically vertically oriented. Over long fracture closure times, and as the viscosity of the fracturing fluid decreases after the fracturing treatment, the proppant tends to settle in the lower portion of the fractures and the upper portions of the fractures close without proppant present to keep them open. Despite all the advances, compositions and methods that provide improved proppant suspension and transportation are continuously sought. [5] Formulation of gelled or viscosified fracturing fluids usually requires equipment and mixing steps designed for this purpose. At the time of proppant addition, the carrier fluid may exhibit poor solid suspending properties and vigorous agitation is required to prevent gravity segregation of the solids. Viscosifying agents such as polymers (with or without crosslinkers) and/or viscoelastic surfactants are added thus improving transport. Unfortunately, formulations of carrier fluids with conventional proppants require a high degree of fluid gelation to maintain suspension of the relatively heavy particles. Even with heavy gelation, such suspensions are further subject to particle settling within a matter of hours, particularly in the presence of vibration. This necessitates well defined mixing capabilities in order to homogeneously re- suspend the proppants in high viscosity suspension gels on-site. Significant costs are further incurred for the chemicals, equipment and processing time in order to gel the carrier fluid. Pumpable suspensions which do not exliibit particle settling are therefore desired.

BRIEF DESCRIPTION

[6] In an embodiment, there is provided a method of fracturing a subterranean formation penetrated by a well that involves injecting a fracturing fluid into a subterranean formation at a pressure effective to fracture the formation, where the fracturing fluid comprises a carrier fluid, a proppant, and a buoyant additive having a hydrophobic surface, the buoyant additive being present in an amount effective to suspend at least a portion of the proppant in the fracturing fluid, where the buoyant additive has had its surface modified with a surface modifying agent.

[7] In another embodiment, there is provided a treatment fluid that includes a carrier fluid, a proppant, and a buoyant additive having a hydrophobic surface, the buoyant additive being present in an amount effective to suspend at least a portion of the proppant in the fracturing fluid, where the buoyant additive has had its surface modified with a surface modifying agent.

[8] '^"Buoyant additive" shall refer to a relatively lightweight material that acts as a "vessel" or "boat" for proppant providing better suspension for proppant transport and less settling for the proppant and keeps proppant in suspension when using a selected ungelled or weakly gelled earner fluid (e.g., ungelled or weakly gelled or lightly gelled water, brine or completion brine, other aqueous-based fluid, slick water, or other suitable fluid). Such additive is composed of at least one lightweight material porous or non-porous and a surface modifying agent.

[9] '"Weakly gelled" or "lightly gelled" carrier fluid shall refer to a carrier fluid having minimum sufficient polymer, or other viseosifier or friction reducer to achieve friction reduction when pumped downhole (e.g.. when pumped down tubing, work string, casing, coiled tubing, drill pipe, etc.), and/or may be characterized as having a polymer or viseosifier concentration from about 1 pounds of polymer or viscoelastic surfactant per thousand gallons (about 0.12 kg/'m') of base fluid to about 25 pounds of polymer or viscoelastic surfactant per thousand gallons (about 3 kg/m^J) base fluid; alternatively from about 10 independently to about 20 pounds of polymer or viscoelastic surfactant per thousand gallons of base fluid (about 1.2 to about 2.4 kg/m'); and/or as having a viscosity of from about 1 independently to about 10 to about 40 centipoises, alternatively from about 5 independently to about 40 centipoises, or power-law n' of less than about 0.25 independently to about 0.75; alternatively about 0.4.

[10] An "ungelled carrier fluid" is a carrier fluid having no cross! inked polymer or other viscosifer, e.g. a viscoelastic surfactant (VES). The ungelled carrier fluid may contain a friction reducer known in the art to create "slickwater", which are pumped at high rates (e.g. from about 60 to about 100 bbl/minute (about 9.5 to about 15.9 kiloli- ters/minute), and which may have sufficient friction reducers to reduce friction pressures up to 70% as compared with water without the friction reducer.

[11] The disclosed buoyant additive materials may be employed with carrier fluids that are gelled, non-gelled, or that have a reduced or lighter gelling requirement as compared to carrier fluids employed with conventional fracture treatment/sand control methods. In one embodiment employing one or more of the disclosed substantially neutrally buoyant particulate materials and a brine carrier fluid, mixing equipment need only include such equipment that is capable of (a) mixing the brine (dissolving soluble salts), and (b) homogeneously dispersing in the substantially neutrally buoyant particulate material. "Neutrally buoyant" is defined herein as having the same specific gravity as the carrier fluid in which the buoyant additive is present so that it does not appreciably rise or fall (due to gravity) over time.

[12] Examples of suitable buoyant additive materials for use in aqueous based carrier fluids include, but are not limited to, surface modified woven or non-woven fabrics that were made superhydrophobic by surface modification using nanoparticles such as silica, alumina, vanadium pentoxide; organic moieties containing hydrophobic elements such as fluorine or silicones that can be adsorbed; covalently bonded or oppositely charged to the fabric and is thus deposited onto the fabric through charge attraction. Furthermore, the fabric or additive can be conferred with a charge to better attach or associate the fabric to or with the hydrophobic moieties.

DETAILED DESCRIPTION

[13] It has been discovered that treatment fluids having excellent proppant suspension and transportation abilities can be obtained by combining a small amount or concentration of a buoyant additive of a selected size, and other physical and chemical properties with a proppant and a carrier fluid. In particular, it has been discovered that the addition of a buoyant additive comprising a filament in turn comprising a material coated or at least partially coated with one or more coatings that confer superhydrophobic properties to the filament providing it with carrier capacity significantly improves the suspension of proppant particles even in a low viscosity carrier properties. A low viscosity treatment fluid can be pumped downhole with lower horsepower and/or inj ection rate as compared to a high viscosity treatment fluid. Thus, the discovery provides a performance and/or cost effective means to treat a subterranean formation. Of course, the buoyant additive can also be used in a viscous fluid to improve farfield proppant placement and the proppants' suspension ability, and delay settling within the fracture after the viscous fluid is broken. By "farfield" is meant from at least about 5 ft (about 1.5 m) independently to about 3000 ft (about 910 m) from the wellbore; alternatively from at least about 10 (about 3 m) independently to about 1000 ft (about 305 m) from the wellbore. [14] "Buoyant additive" shall refer to the combination of physical, morphological, textual, chemical, and surface energy properties of the relatively lightweight material that acts as a vessel or boat for proppant providing with better integral suspension for transport and less settling of proppant in hydraulic fractures. Such additive is additionally composed of at least one lightweight material, that is porous or non-porous, and a surface modifying agent.

[15] A "superhydrophobic" surface means a surface that has energy properties that make the surface extremely difficult to water wet because of its chemical composition and/or morphological/geometric microstructure. A superhydrophobic surface has at least one of the following characteristics: a static contact angle greater than about 130°, alternatively greater than about 140°, or greater than about 150°; a contact angle hysteresis less than about 20°, alternatively less than about 15°, or less than about 10°; or a roll-off angle less than about 10° or alternatively less than about 5°. In one non- limiting embodiment, a superhydrophobic surface has two of these characteristics. In another embodiment, a superhydrophobic additive has all three characteristics.

[16] The buoyant additive comprises a core and one or more coating layers disposed on the core. The core comprises a natural filament or fiber, a synthetic filament or fiber, or a combination comprising at least one of the foregoing. Synthetic fibers include, but are not necessarily limited to, cotton fibers, polyamide fibers, polyester fibers, acrylic fibers, sulfur fibers, modacrylic fibers, polyolefin fibers, regenerated cellulose fibers, polyvinyl chloride fibers, polyvinylidene chloride fibers, polyvinyl alcohol fibers, polybenzimidazole fibers, aramid fibers, polyhydroquinone-diimidaz- opyridine fibers, or a combination comprising at least one of the foregoing. As used herein, "filament" and "fiber" means a relatively flexible, unit of matter having a high ratio of length to width across its cross-sectional area perpendicular to its length. In one non-limiting embodiment, the fiber length is at least 100 times its diameter or width. The cross section of the fiber described herein can be any shape, for example flat, circular or bean shaped. The fibers include woven and non-woven fibers; generally the filaments or fibers are physically connected together in some way, but are not necessarily so connected that they could not be disconnected (e.g. unwoven) give sufficient effort and/or time. It is appreciated that the core can be a fabric.

[17] It will be appreciated that while the buoyant additive may be at least initially configured to have a generally flat structure and/or small cross-sectional profile to permit them to be pumped downhole to be introduced into hydraulic fractures, they may have, or optionally undergo a shape change to have a three-dimensional (3D) structure as well configured to connect with and engage each other, the fracture face(s), and proppant(s).

[18] It will be appreciated that while the buoyant additive may be at least initially configured to have a generally flat structure and/or small cross-sectional profile to permit them to be pumped downhole to be introduced into hydraulic fractures, they will have, or optionally undergo a shape change to have a three-dimensional (3D) structure as well configured to connect with and engage each other, the fracture face(s), and proppant(s). In one non-limiting embodiment at least a portion of the buoyant additives introduced into the fractures is hydrolyzable, meaning that of multiple types of buoyant additives introduced, some buoyant additives are hydrolyzable, or relatively more hydrolyzable than others. Alternatively, or additionally, in another non-restrictive version, at least a portion of each buoyant additive is hydrolyzable. In these optional embodiments of the buoyant additive, the buoyant additive is configured to undergo a shape change in response to hydrolyzing, change in temperature, change in pH, change in the nature of the surrounding fluid, and combinations thereof. In another non-limiting embodiment, the buoyant additives may comprise shape-memory polymers (SMPs) or the like thermo-responsive polymers engineered and designed so that at an elevated temperature they have a more convoluted shape that occupies more three-dimensional volume, such as a coil, spring, spiral, corkscrew, box, cube, pyramid, or the like, but are shaped and frozen at a lower temperature (below the glass transition temperature, T_g, of the polymer) into a generally linear shape that permits them to be readily injected as part of a fracturing fluid.

[19] The surface modifier includes, but is not necessarily limited to, wax, silica, an organo silane, a siliconate, a silicate, a silsesquioxane, phosphonic acids, metal oxides nanoparticles that confer the superhydrophobicity through patterning on the surface of the fabric, transition metal oxides containing hydrophobic organic moieties, post-transition metal oxides containing hydrophobic organic moieties, silicon, fluori- nated carbon based compounds, polymers, a derivative thereof, or a combination comprising at least one of the foregoing. The surface modifier contains either the coating material or a product derived from the coating material. Suitable transition metal oxides include, but are not necessarily limited to vanadium, titanium, zirconium, niobium, molybdenum, tantalum, chromium, and may also include aluminum (a post- transition metal) and silicon (a metalloid).

[20] Suitable silica materials include, but are not necessarily limited to, silica nanoparticles, silica microparticles, a silica sol or colloidal silica. Exemplary siliconate includes, but is not necessarily limited to, potassium methyl siliconate and sodium methyl siliconate. Exemplary silicate includes tetraethyl orthosilicate. Silsesquioxane includes polymethylsilsesquioxane. Nanoparticles are defined herein as having an average particle size distribution between 1 to 999 nanometers, inclusive; alternatively between 1 and 100 nanometers. Microparticles are defined herein as having an average particle size distribution between 1 independently to 999 μιτι in size; alternatively between 10 independently to 100 μιτι in size. The term "independently" as used herein with respect to a range means that any lower threshold can be used together with any upper threshold to give an acceptable alternative range.

[21 ] The buoyant additives are prepared by a method including, but not necessarily limited to, a solution-immersion method, chemical vapor deposition, a sol-gel method, casting, self-assembly, a layer-by-layer method, an electrospinning method, a phase separation method, or the like. Exemplary methods are described in Journal of Surface Engineering Materials and Advanced Technology, 2012, 2, 76-94. Surface modification includes, but is not necessarily limited to at least partially coating or entirely coating a filament or plurality of filaments with a coating or layer.

[22] The surface modifier can be applied in one layer, more than one layer, more than two layers, more than three layers, more than four layers, or more than five layers. The maximum number of the surface modifier layers is not limited and can be fifteen or ten.

[23] In another non-limiting example, the buoyant additive comprises a core of woven and/or non-woven textile filaments or fibers. Natural and/or synthetic filaments can form textiles to suit a wide range of configurations of buoyant additive shapes. The filaments can be surface modified with superhydrophobic agents or other surface modifying agents before or after forming into textile. Textile will also allow engineering of the buoyant additive mesh thickness, pore structure and sizes, and additive densities, among other properties if mixed with inorganic core agents.

[24] In one non-limiting example a 3D mesh "sandwich" of specific gauged width, thickness, length and mesh density, geometric proppant transport shape, and filament surface coating, can be non-limiting examples of a proppant transport agents new to the art of hydraulic fracturing.

[25] The buoyant additive can be in a number of formats, shapes and/or configurations, including, but not necessarily limited to, a sheet, plate, boat, roving, fiber, strand, braid, mat, and the like, or a combination thereof. The buoyant additive can be of various dimensions, predominantly having a two-dimensional aspect ratio (i. e., ratios of length to width, at an assumed thickness; diameter to thickness; or surface area to cross-sectional area, for plate-like additives) of greater than or equal to about 4: 1, specifically greater than or equal to about 5 :1, more specifically greater than or equal to about 10: 1, and still more specifically greater than or equal to about 15 : 1. Similarly, the two-dimensional aspect ratio is less than or equal to about 50: 1, specifically less than or equal to about 30: 1, and alternatively less than or equal to about 20:1. Suitable coating thickness ranges may in one non-limiting embodiment be from about 4 nm independently to about 400 nm; alternatively from about 5 nm independently to about 200 nm; and in another non-restrictive version from about lOnm independently to about 100 nm.

[26] The buoyant additive is useful to increase the suspension and transportation of proppant particles. The proppant particles have a size from 1 μιτι independently to 2,000 μηι, alternatively from 10 μπι independently to 1,000 μηι, in another non-limiting embodiment from 10 μηι independently to 500 μιτι, and in a different non-restrictive version from 200 μηι independently to 850 μηι. Further, the proppant particles can have any shape including, but not necessarily limited to, spherical, angular, and polyhedral and are monodisperse or polydisperse with an average particle size distribution that is unimodal or multimodal, e.g., bimodal.

[27] The proppant can comprise, but is not necessarily limited to, sand, glass beads, walnut hulls, metal shot, resin-coated sands, intermediate strength ceramics, sintered bauxite, resin-coated ceramic proppants, plastic beads, polystyrene beads, thermoplastic particulates, thermoplastic resins, thermoplastic composites, thermoplastic aggregates containing a binder, synthetic organic particles including nylon pellets and ceramics, ground or crushed shells of nuts, resin-coated ground or crushed shells of nuts, ground or crushed seed shells, resin-coated ground or crushed seed shells, processed wood materials, porous particulate materials, and combinations comprising at least one of the foregoing.

[28] Advantageously the buoyant additives improve the proppant suspension and transportation in a low viscosity carrier such as slickwater, freshwater, brine, aqueous acid, aqueous base, or a combination comprising at least one of the foregoing. The buoyant additives also improve the proppants' suspension and transportation properties in a high viscosity fluid. A high viscosity fluid includes a gelled fluid or a foam.

[29] The treatment fluid such as a hydraulic fracturing composition is useful e.g., to transport and dispose proppant particles into a fracture. The buoyant additive is effective to prevent or inhibit proppant particles from settling and therefore increase overall fractured surface area. According to an embodiment, the hydraulic fracturing fluid composition is used to form the fracture. In an embodiment, a process for disposing a plurality of proppant particles in a fracture includes disposing a hydraulic fracturing composition in a downhole environment. In this method, forming a fracture in the downhole environment is accomplished by applying hydraulic force on the downhole environment from the hydraulic fracturing fluid, and disposing the hydraulic fracturing fluid in the fracture. In this manner, the proppant particles do not settle, and are inhibited from settling, to the bottom of the fracture. In one non-limiting embodiment less proppant has settled in the fracture as compared with an otherwise identical method absent the buoyant additive. The downhole environment is, e.g., a reservoir temperature, formation water, formation rock, sand, and the like, which contains, e.g., pores or veins of various sizes in such rock, sand, and the like.

[30] The mechanism by which the buoyant additive associates or is connected with the proppant is the buoyancy, in particular neutral buoyancy of the buoyant additive and hydrophobicity that keeps the additive suspended in the fluid. In this case the buoyant additive acts as a transport vessel to the proppant.

[31] The amount of proppant in the carrier fluid may range from about 0.25 ppa (pounds per proppant added) (about 0.03 kg/L) independently to about 12 ppa (about 1.4 kg/L); alternatively from about 0.25 ppa (about 0.03 kg/L) independently to about 8 ppa (about 1 kg/L). Ppa is equivalent to lb/gallon added. The amount of buoyant additive relative to the amount of proppant may range from about 0.01 wt% independently to about 30 wt%, alternatively from about 0.5 wt% independently to about 8 wt%, in another non-limiting embodiment from about 0.1 independently to about 10 wt%, and in a different non-restrictive embodiment from about 1 wt% independently to about 5 wt%.

[32] All ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other. The ranges are continuous and thus contain every value and subset thereof in the range. Unless otherwise stated or contex- tually inapplicable, all percentages, when expressing a quantity, are weight percentages. As used herein, "combination" is inclusive of blends, mixtures, alloys, reaction products, and the like. Further as used herein, "a combination thereof refers to a combination comprising at least one of the named constituents, components, compounds, or elements, optionally together with one or more like constituents, components, compounds, or elements not named. The use of the terms "a" and "an" and "the" and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. "Or" means "and/or" as defined herein unless noted otherwise or where such meaning would be contextually inapplicable.

[33] The modifier "about" used in connection with a quantity is inclusive of the stated value and has the meaning dictated by the context (e.g., it includes the degree of error associated with measurement of the particular quantity).

[34] While one or more embodiments have been shown and described, modifications and substitutions may be made thereto without departing from the scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustrations and not limitation. Embodiments herein can be used independently or can be combined.

[35] As used herein, the terms "comprising," "including," "containing," "characterized by," and grammatical equivalents thereof are inclusive or open-ended terms that do not exclude additional, unrecited elements or method acts, but also include the more restrictive terms "consisting of and "consisting essentially of and grammatical equivalents thereof. As used herein, the term "may" with respect to a material, structure, feature or method act indicates that such is contemplated for use in implementation of an embodiment of the disclosure and such term is used in preference to the more restrictive term "is" so as to avoid any implication that other, compatible materials, structures, features and methods usable in combination therewith should or must be, excluded.

[36] The present invention may suitably comprise, consist of or consist essentially of the elements disclosed and may be practiced in the absence of an element not disclosed. For instance, there may be provided a method of fracturing a subterranean formation penetrated by a well, the method that consists essentially of or consists of injecting a fracturing fluid into a subterranean formation at a pressure effective to fracture the formation, where the fracturing fluid comprises, consists essentially of, or consists of a carrier fluid, a proppant, and a buoyant additive having a hydrophobic surface, the buoyant additive being present in an amount effective to suspend at least a portion of the proppant in the fracturing fluid, where the buoyant additive has had its surface modified with a surface modifying agent. [37] There may be further provided a treatment or fracturing fluid consisting essentially of or consisting of a carrier fluid, a proppant, and a buoyant additive having a hydrophobic surface, the buoyant additive being present in an amount effective to suspend at least a portion of the proppant in the fracturing fluid, where the buoyant additive has had its surface modified with a surface modifying agent.

Claims

CLAIMS What is claimed is:

1. A method of fracturing a subterranean formation comprising:

injecting a fracturing fluid into a subterranean formation at a pressure effective to fracture the formation, where the fracturing fluid comprises:

a carrier fluid;

a proppant; and

characterized by a buoyant additive having a hydrophobic

surface, the buoyant additive being present in an amount effective to suspend at least a portion of the proppant in the fracturing fluid, where the buoyant additive has had its surface modified with a surface modifying agent.

2. The method of claim 1 where the buoyant additive comprises a plurality of filaments physically connected together, where the filaments are at least partially coated with a coating that confers superhydrophobicity to the filaments.

3. The method of claim 2 where the thickness of the coating ranges from 4 nm to 100 nm.

4. The method of claim 1 , 2, or 3 where the surface modifying agent is selected from the group consisting of wax, silica, an organo silane, a siliconate, a silicate, a silsesquioxane, phosphonic acids, metal oxides nanoparticles that confer the superhydrophobicity through patterning on the surface of the fabric, transition metal oxides, post-transition metal oxides, silicon, fluorinated carbon based compounds, polymers, and combinations thereof.

5. The method of claim 4 where the amount of buoyant additive based on the amount of proppants ranges from 0.01 wt% to 30 wt% of proppant.

6. The method of claim 4 where the amount of proppant in the carrier ranges from 0.25 ppa to 12 ppa (0.03 kg/L to 1.4 kg/L).

7. The method of claim 1, 2, or 3 where the method further comprises:

creating at least one fracture; and

permitting at least one fracture to close against the proppant.

8. The method of claim 7 where less proppant has settled in the fracture as compared with an otherwise identical method absent the buoyant additive.

9. The method of claim 1 further comprising the buoyant additive undergoing a shape change after the fracturing fluid is injected into the subterranean formation.

10. A fracturing fluid comprising:

a carrier fluid;

a proppant; and

characterized by a buoyant additive having a hydrophobic surface, the buoyant additive being present in an amount effective to suspend at least a portion of the proppant in the fracturing fluid, where the buoyant additive has had its surface modified with a surface modifying agent.

11. The fracturing fluid of claim 10 where the buoyant additive comprises a plurality of filaments physically connected together, where the filaments are at least partially coated with a coating that confers superhydrophobicity to the filaments.

12. The fracturing fluid of claim 11 where the thickness of the coating ranges from 4 nm to 100 nm.

13. The fracturing fluid of claim 10, 11, or 12 where the surface modifying agent is selected from the group consisting of wax, silica, an organo silane, a siliconate, a silicate, a silsesquioxane, phosphonic acids, metal oxides nanoparticles that confer the superhydrophobicity through patterning on the surface of the fabric, transition metal oxides, post-transition metal oxides, silicon, fluorinated carbon based compounds, polymers, and combinations thereof.

14. The fracturing fluid of claim 10, 1 1 , or 12 where the amount of buoyant additive based on the amount of proppants ranges from 0.01 wt% to 30 wt% of proppant.

15. The fracturing fluid of claim 10, 1 1 , or 12 where the amount of proppant in the carrier ranges from 0.25 ppa to 12 ppa (0.03 kg/L to 1.4 kg/L).

16. The fracturing fluid of claim 10, 1 1 , or 12 where the buoyant additive is configured to undergo a shape change in response to hydrolyzing, change in temperature, change in pH, change in the nature of the surrounding fluid, and combinations thereof.