A method of drilling in a subterranean formation. A method may include providing a direct emulsion drilling fluid comprising an aqueous fluid, an oil, and a polysorbate emulsifier; circulating the direct emulsion drilling fluid from a surface, through a wellbore, and back to the surface; and extending the wellbore in the subterranean formation while circulating the direct emulsion drilling fluid.

A method of repairing a well is provided. The method includes injecting a brine solution into the well, injecting carbon dioxide into the well, and reacting the brine solution in the reservoir rock with the carbon dioxide to form calcite such that calcite precipitates into the desired flow path between a cold well and a hot well to effectively repair short circuits within the EGS reservoir.

An acid treatment composition includes a nonionic surfactant, including nonyl phenol ethoxylate. The acid treatment composition also includes a retarding agent comprising magnesium, an acid, and water. The nonionic surfactant and retarding agent of the acid treatment composition are reactive with carbonate.

A drilling fluid and method for drilling in a coal containing formation. The method includes: providing a mixed metal-viscosified drilling fluid including at least 1% potassium salt; circulating the drilling fluid through the well; and drilling into a coal seam.

Clay stabilization compositions include one or a plurality of triamino compounds and/or derivatives thereof, fluids containing an effective amount of the clay stabilization compositions and methods for making and using same.

Amidoamine-based gemini surfactants having dual chains connected via an alkenylene or alkynylene linker. Each chain contains a quaternary ammonium head group and an ethoxylated alkyl tail. A water-based drilling fluid containing the gemini surfactant is also provided. As examined by linear swelling and free swelling tests, the gemini surfactant is effective in reducing clay swelling.

Disclosed herein are optical swell meters and methods for using them to measure fine-scale variations in the swelling behavior of shale specimens. In an embodiment, the optical swell meters can include: a glass imbibition chamber containing a specimen, where an imbibition fluid is located within the glass inhibition chamber and at least partially covering the specimen; a digital camera set a distance away from the chamber and facing the chamber; and a light source, where the light source illuminates the specimen. The method of using the optical swell meter can provide a swelling strain profile of the shale specimens during its interaction with the imbibition fluid.

A method of detecting an amine-based additive in a wellbore servicing fluid (WSF) comprising contacting an aliquot of WSF with an amine detector compound and an aqueous salt solution to form a detection solution; wherein the aqueous salt solution comprises an inorganic salt and organic carboxylate salt; wherein the WSF comprises the amine-based additive; and wherein the detection solution is characterized by at least one absorption peak wavelength in the range of 380-760 nm; detecting an absorption intensity for detection solution at a wavelength within about ±20% of the at least one absorption peak wavelength; comparing the absorption intensity of detection solution at the wavelength within about ±20% of the at least one absorption peak wavelength with a target absorption intensity of amine-based additive to determine the amount of amine-based additive in WSF; and comparing the amount of amine-based additive in WSF with a target amount of amine-based additive.

Multiple charged cationic compounds, which are derived from polyamines through an aza-Michael addition with an α, β-unsaturated carbonyl compound, in a clay treatment composition to reduces clay swelling, clay migration, and sludge formation in a subterranean formation in oil and gas operations are provided. The disclosed methods or compositions are found to be more effective than those methods or compositions commonly used for reducing clay swelling, clay migration, and sludge formation.

A method of repairing a well is provided. The method includes injecting a brine solution into the well, injecting carbon dioxide into the well, and reacting the brine solution in the reservoir rock with the carbon dioxide to form calcite such that calcite precipitates into the desired flow path between a cold well and a hot well to effectively repair short circuits within the EGS reservoir.