Well fluids and methods are provided that can be used for stabilizing a shale formation, especially during drilling of a well into or through a shale formation. The well fluids include: (i) a continuous water phase; (ii) a viscosity-increasing agent, wherein the viscosity-increasing agent comprises water-soluble hydrophilic polymer; (iii) a fluid loss control agent; and (iv) a cyclodextrin-based compound. The methods of drilling include the steps of: (A) introducing the well fluid into a zone of a subterranean formation; and (b) drilling the zone.

Methods and compositions including silicate shale inhibitor additives. In some embodiments, the methods include introducing a shale inhibitor additive comprising a silicate anion and a quaternary ammonium cation into a treatment fluid; introducing the treatment fluid into a wellbore penetrating at least a portion of a subterranean formation that comprises shale; and allowing the shale inhibitor additive to interact with the shale in the subterranean formation to at least partially inhibit the shale.

Provided is an injection fluid that may include a nanoemulsion having an oil phase dispersed in an aqueous phase, and non-superparamagnetic magnetic nanoparticles that are present in the dispersed oil phase. Further provided is a method for preparing an injection fluid that may include preparing a nanoemulsion from an aqueous phase and an oil phase having non-superparamagnetic magnetic nanoparticles therein, and may be used to form nanodroplets of the non-superparamagnetic magnetic nanoparticles. Further provided is a method for tracking movement of an injection fluid. The method may include introducing a tagged injection fluid into a hydrocarbon-containing reservoir, the tagged injection fluid may be a nanoemulsion that includes: an aqueous phase, an oil phase dispersed in the aqueous phase, and non-superparamagnetic nanoparticles that are present in the dispersed oil phase; and tracking the movement of the tagged injection fluid.

A composition of matter including a fluorescent assembly and a drilling fluid is provided. The fluorescent assembly includes a matrix material and a plurality of fluorophores held within the matrix material and has an average particle size of at least one millimeter. A method includes introducing the fluorescent assembly into a drilling fluid and circulating the drilling fluid through a well during a drilling operation that creates formation cuttings such that the fluorescent assembly interacts with the formation cuttings, creating tagged cuttings. The method further includes collecting returned cuttings from the circulating drilling fluid at a surface of the well, detecting the presence of the fluorescent assembly on the returned cuttings to identify the tagged cuttings, and correlating the tagged cuttings with a drill depth in the well at a time during the drilling operation.

Polyacrylamide (PAM)-coated nanosand that may be a relative permeability modifier (RPM) and that is applied to treat a wellbore in a subterranean formation. The treatment may be for excess water production. The PAM-coated nanosand is PAM-hydrogel-coated nanosand. The PAM-coated nanosand os nanosand coated with PAM hydrogel. The PAM hydrogel includes crosslinked PAM in water. Application of the PAM-coated nanosand may reduce water production from the subterranean formation into the wellbore. The PAM hydrogel of the PAM-coated nanosand may expand in a water zone of the subterranean formation to restrict water flow into the wellbore. The PAM hydrogel of the PAM-coated nanosand may contract in an oil zone of the subterranean formation so not to significantly restrict crude oil flow into the wellbore.

A composition for use in a wellbore activity, the composition comprising a stabilized monovalent iodide brine, the stabilized monovalent iodide brine comprises a monovalent salt system, the monovalent salt system comprises a monovalent iodide; a primary iodide stabilizer, the primary iodide stabilizer operable to remove free iodine, prevent the formation of free iodine, and suppress TCT; and an aqueous fluid, where the stabilized monovalent iodide brine has a density greater than 10 lb/gal, where the stabilized monovalent iodide brine has a TCT of less than or equal to 70 deg F.

The methods of suspending at least one weighting agent in a drilling fluid include synthesizing carbon nanotubes via chemical vapor deposition on iron oxide catalyst nanoparticles to form a quantity of nanoparticles. Individual nanoparticles of the iron oxide catalyst nanoparticles include a transition metal disposed on iron oxide. The embodiments further include adding a quantity of nanoparticles to the drilling fluid which results in an amount of carbon nanotubes dispersed within the drilling fluid. The dispersion of the quantity of nanoparticles increases the value of at least one of a Newtonian viscosity, a yield point, a plastic viscosity, and a density of the drilling fluid with the dispersed nanoparticles versus a similar or equivalent drilling fluid without the nanoparticle dispersion. The method may further include adding at least one weighting agent which will become suspended in the drilling fluid.

Disclosed herein is a nanoparticle modified fluid that includes nanoparticles that are surface modified to increase a viscosity of the nanoparticle modified fluid and that have at least one dimension that is less than or equal to about 50 nanometers; nanoparticles that are surface modified to increase a viscosity of the nanoparticle modified fluid and that have at least one dimension that is less than or equal to about 70 nanometers; and a liquid carrier; wherein the nanoparticle modified fluid exhibits a viscosity above that of a comparative nanoparticle modified fluid that contains the same nanoparticles but whose surfaces are not modified, when both nanoparticle modified fluids are tested at the same shear rate and temperature.

Methods and systems for the treatment of wells are disclosed. A method for treating a well comprises providing a treatment fluid comprising calcium-aluminate cement, water, and a cement set retarder; and introducing the treatment fluid into a wellbore. A system for treating a well comprises a treatment fluid comprising calcium-aluminate cement, water, and a cement set retarder; a vessel to contain the treatment fluid; a pumping system coupled to the vessel to pump the treatment fluid; and a conduit coupled to the pumping system.

A method for the fracking or stimulation of a hydrocarbon-bearing formation, said method comprising the steps of: providing a wellbore in need of stimulation; inserting a plug in the wellbore at a predetermined location; inserting a perforating tool and a spearhead or breakdown acid into the wellbore; positioning the tool at said predetermined location; perforating the wellbore with the tool thereby creating a perforated area; allowing the spearhead acid to come into contact with the perforated area for a predetermined period of time sufficient to prepare the formation for fracking or stimulation; removing the tool from the wellbore; and initiating the fracking of the perforated area using a fracking fluid. Also disclosed is a corrosion inhibiting composition for use with the acid composition.