A fluid for use in hydraulic fracturing contains underivatized guar or a guar gum derivative as viscosifying or gelling polymer, a crosslinking agent, carbon dioxide as foaming agent and urea and, optionally, a bifunctional organic compound containing at least one hydroxyl group and at least one quaternary group and, optionally, a non-gaseous foaming agent. The fluid may be characterized by a low pH such as a pH than or equal to 3.0 and less than or equal to 5.0.

This document relates to energetic salts that contain an organic cation and an oxidizing anion and methods of using the energetic salt compositions, including methods of hydraulic fracturing, pressure pulse fracturing, formation damage removal, and lowering the viscosity of heavy oil.

A composition for fracking an unconventional reservoir including hard water and liquid carbon dioxide for in-situ generation of proppant particles. A method for fracturing a rock formation in an unconventional reservoir at high temperature and pressure conditions, including pumping the composition into the rock formation and precipitating calcite and aragonite crystals inside the rock formation.

There is provided a method for mitigating fracturing hits on an underground well consisting of inserting a multi-phase composition comprising gas and a nanoparticle fluid into a pre-existing well for reducing of not eliminating any fracture driven interference at the pre-existing well; and a multi-phase composition for mitigating fracturing hits on an underground well, which consists of a gas and nanoparticle fluid combined to form a well treatment fluid adapted to be injectable into the underground well for resisting fracturing hits on the underground well.

Compositions comprising a neutral surfactant or a reaction product thereof and a reaction product of a saccharide polymer and a fatty acid may be obtained in the presence of water and a hydroxide base (optionally in the presence of the neutral surfactant), the saccharide polymer comprising a dextran, a dextrin compound, or any combination thereof. The reaction product of the saccharide polymer and the fatty acid may be present at a concentration effective to lower surface tension of the neutral surfactant. Depending on the fatty acid identity, among other factors, the compositions may promote emulsification or de-emulsification. In addition, the compositions may promote foam formation under appropriate conditions. Treatment fluids comprising the compositions, including foamed treatment fluids, may be introduced into a subterranean formation to perform a treatment operation in which fluid emulsification or de-emulsification may occur. The reaction products may be incorporated in soaps and other personal care products.

Certain foamed gel treatment fluids and methods of using the treatment fluids in wellbores penetrating subterranean formations are provided. In one embodiment, the treatment fluids comprise: an aqueous base fluid, a gas, a plurality of particulates, and a plurality of swellable particles each comprising a material having a first monomer, a second monomer, and a third monomer comprising a foamable surfactant. In one embodiment, the methods comprise: preparing a treatment fluid comprising an aqueous base fluid and a swellable particle that comprises a material having a first monomer, a second monomer, and a third monomer comprising a foamable surfactant; introducing the treatment fluid into a wellbore penetrating at least a portion of a subterranean formation; and blending the treatment fluid while in the wellbore to form a foamed gel.

A method of stimulating petroleum production includes introducing a fracturing fluid into a petroleum formation, thereby creating at least one fracture to stimulate the petroleum production. The fracturing fluid is introduced into the petroleum formation at a pressure above the breakdown pressure of the formation. The fracturing fluid includes a plurality of proppants each including a proppant particle and a coating. The coating includes a hydrophobic coating, a cross-linked hydrogel, or both. From 1 to 50 wt. % of the plurality of proppants includes micro proppants having a particle size ranging from 0.5 to 150 μm, and from 50 to 99 wt. % of the plurality of proppants includes macro proppants having a particle size of 100 mesh or greater.

Systems, compositions, and methods usable to stimulate a formation include a first supply subsystem adapted to provide a first medium to the formation and a pressure subsystem that includes a pump in communication with the first medium to pressurize the first medium to a pressure sufficient to stimulate the formation. Usable media can include non-gelled liquid alkanes, halogenated hydrocarbons, foamed hydrocarbons, a fluidized solid proppant material that behaves as a liquid under threshold conditions, or a liquid material adapted to solidify under threshold conditions. A proppant can be supplied in addition to the first medium when performing fracturing operations. Usable proppant can include materials having a size or density adapted to facilitate buoyancy, hollow materials, composite materials, porous materials, or crystalline materials.

A composition includes a nonionic fluorinated polymeric surfactant, a nonfluorinated surfactant, and a scale treatment. Additionally, a method for scale treatment is provided. The method includes injecting gas into the aforementioned composition to produce a foam and injecting the foam into a formation. In the formation, the foam may be exposed to a first temperature at which it has a first viscosity. The foam may be maintained inside the formation for a period of time, and then recovered from the formation, at which point it is exposed to a second temperature and has a second viscosity.

A method for acid treating a carbonate reservoir with an attenuated acid formulation is provided. The method includes mixing an acidic compound with a hygroscopic chemical to form the attenuated acid formulation, and injecting the attenuated acid formulation into a carbonate formation.