Abstract: Compositions may include a calcium lignosulfonate salt having a chemical structure (I), wherein a total number of syringyl groups is 2 to 10. The compositions may further include an alcohol, an aldehyde, and water. Cement slurries may include a lignosulfonate-based cement dispersant including a calcium lignosulfonate salt having a chemical structure (I), an alcohol, an aldehyde, and water, wherein a total number of syringyl groups in the chemical structure (I) is 2 to 10. The cement slurries may further include a cement and water. Methods may include introducing a cement slurry into a wellbore penetrating a subterranean formation, wherein the cement slurry comprises a lignosulfonate-based cement dispersant, a cement, and water, and allowing the cement slurry to set to a concrete in a downhole zone of interest.

Abstract: Described is a method for assessing quality of an amine-based shale inhibitor in drilling fluid. A relationship between a concentration of the amine-based shale inhibitor in a drilling fluid and turbidity is established by preparing drilling fluid solutions with varying concentrations of the amine-based shale inhibitor, allowing the drilling fluid solutions to form precipitates, and analyzing turbidity of the drilling fluid solutions. A sample of a drilling fluid with an unknown concentration of amine-based shale inhibitor is obtained. Using the established relationship, a concentration of the amine-based shale inhibitor in the sample of the drilling fluid is estimated.

Abstract: Methods for making and using an invert-emulsion drilling fluid, and the invert-emulsion drilling fluid are provided. An exemplary invert-emulsion drilling fluid includes a C-36 dimer diamine dihydrochloride salt (CDDH), an aqueous solvent, a non-aqueous solvent, an emulsifier, and calcium chloride.

Abstract: The present disclosure relates to cement compositions including Portland cement and volcanic ash. An exemplary cement composition includes about 10 wt % to about 85 wt % of Portland cement, and about 10% by weight of cement (BWOC) to about 70% BWOC of volcanic ash.

Abstract: A method of reducing water production in a wellbore may include introducing an alkaline nanosilica dispersion to the wellbore such that it contacts a water producing zone of the wellbore, introducing a sodium bicarbonate activator to the wellbore such that it contacts the alkaline nanosilica dispersion in the water producing zone, and forming a gelled solid from the water shutoff material in the water producing zone, thereby reducing water production in the wellbore.

Abstract: A loss circulation material (LCM) includes an alkaline nanosilica dispersion and a formate activator. The formate activator may be present in an amount in a range of 1 wt % to 40 wt % of the loss circulation material. A method of controlling loss circulation in a loss circulation zone (LCZ) in a wellbore includes introducing an alkaline nanosilica dispersion into the wellbore, introducing a formate activator solution into the wellbore, contacting the alkaline nanosilica dispersion with the formate activator, thereby forming a LCM composition, and forming a gelled solid from the LCM in the loss circulation zone. A method of controlling loss circulation in a LCZ in a wellbore includes introducing a LCM that includes an alkaline nanosilica dispersion and a formate activator into the wellbore such that they contact the LCZ, and forming a gelled solid from the LCM in the LCZ.

Abstract: A loss circulation material includes an acidic nanosilica dispersion and a formate activator, which may be present in an amount in a range of 1 wt % to 40 wt % of the loss circulation material. A method to control lost circulation in a lost circulation zone in a wellbore includes introducing an acidic nanosilica dispersion into the wellbore, introducing a formate activator into the wellbore, contacting the acidic nanosilica dispersion with the formate activator, thereby forming a loss circulation material composition, and forming a gelled solid from the loss circulation material in the lost circulation zone. A method of controlling lost circulation in a lost circulation zone in a wellbore includes introducing a loss circulation material comprising an acidic nanosilica dispersion and a formate activator into the wellbore, such that they contact the lost circulation zone, and forming a gelled solid from the loss circulation material in the lost circulation zone.

Abstract: A tool for use in a wellbore includes an annular body having an inner flow passage extending axially therethrough, at least one gripping member positioned around an outer perimeter of a retainer section of the annular body, and a gate member positioned in the inner flow passage. When the gate member is in a closed configuration, an upstream portion of the inner flow passage is sealed from a downstream portion of the inner flow passage by the gate member. When the gate member is in an open configuration, the upstream portion of the inner flow passage is fluidly connected to the downstream portion of the inner flow passage. At least one static mixing blade extends through the downstream portion of the inner flow passage to mix fluid when it flows through the open gate member.

Abstract: A method and system for controlling unwanted water production from a water-producing zone in a subterranean formation are provided. An exemplary method includes flowing an alkaline suspension of nanosilica particles into a wellbore such that it contacts the water-producing zone, and flowing a formate salt solution into the wellbore such that it contacts the alkaline suspension in the water-producing zone producing a composition. The wellbore is shut in a duration of time sufficient for the composition to form a gel that is impermeable to fluid flow.

Abstract: A cement spacer fluid and a method for making and a method for using the cement spacer fluid are provided. The cement spacer fluid includes a polyethyleneimine hydrochloride (PEI HCl) salt, an aqueous solvent, a viscosifier, and a weighting agent.

Abstract: A tool for use in a wellbore includes an annular body having an inner flow passage extending axially therethrough, at least one gripping member positioned around an outer perimeter of a retainer section of the annular body, and a gate member positioned in the inner flow passage. When the gate member is in a closed configuration, an upstream portion of the inner flow passage is sealed from a downstream portion of the inner flow passage by the gate member. When the gate member is in an open configuration, the upstream portion of the inner flow passage is fluidly connected to the downstream portion of the inner flow passage. At least one static mixing blade extends through the downstream portion of the inner flow passage to mix fluid when it flows through the open gate member.

Abstract: A composition of an invert emulsion oil-based drilling fluid is provided. The composition may include an oil phase and an aqueous phase. The oil phase may include an oleaginous fluid, an organophilic clay-based solid viscosifier, and a liquid viscosifier including a POSS. Further provided is a method of introducing the composition including the POSS into a wellbore. After introduction of the composition into the wellbore, the method includes maintaining wellbore conditions to provide a stable rheological property for a period up to about 96 hours in an HPHT section of a wellbore.

Abstract: A composition of an invert emulsion oil-based drilling fluid is provided. The composition may include an oil phase and an aqueous phase. The oil phase may include an oleaginous fluid, an organophilic clay-based solid viscosifier, and a liquid viscosifier including a POSS. Further provided is a method of introducing the composition including the POSS into a wellbore. After introduction of the composition into the wellbore, the method includes maintaining wellbore conditions to provide a stable rheological property for a period up to about 96 hours in an HPHT section of a wellbore.

Abstract: A wellbore fluid composition is provided that includes an aqueous base fluid and at least one ethylene ammonium salt having a number average molecular weight in a range of 250 to 500 grams per mole. A method of drilling a wellbore is also provided. the method includes circulating an aqueous drilling fluid into the wellbore while drilling, wherein the aqueous drilling fluid includes at least one ethylene ammonium salt. The aqueous drilling fluid further includes a pH value from 6.5 to 7.5. The method of drilling a wellbore further includes recovering shale cuttings while maintaining wellbore stability.

Abstract: A method for mitigating loss circulation zones in a wellbore is provided. The method includes synthesizing a carbamate from an amine-curing agent, and the carbamate is mixed with an epoxy resin from the loss control composition. The loss control composition is pumped into a wellbore with a loss circulation zone, wherein the loss control composition flows into the loss circulation zone. The carbamate of the loss control composition is allowed to decompose at wellbore temperatures, wherein the carbamate releases CO2 gas and the amine-curing agent. The CO2 gas foams the epoxy resin, expanding the epoxy resin to fill voids in the loss circulation zone, and the amine-curing agent cures the foamed epoxy resin, forming a loss control material that seals the loss circulation zone.

Abstract: Methods and compositions including introducing a lost circulation material to a zone of interest in a subterranean formation via a wellbore, the zone of interest comprising depleted zones, zones of low pressure, lost circulation zones, fractured zones, and any combination thereof; wherein the lost circulation material comprises an epoxidized linear ?-olefin; a surfactant; a curing agent; and a carbon dioxide gas-generating compound comprising sodium bicarbonate; heating the lost circulation material; and allowing the epoxidized linear ?-olefin to polymerize to a resin and the carbon dioxide gas-generating compound to produce a gas to form a foamed resin in the zone of interest, thereby mitigating a flow of fluids from the wellbore into the subterranean formation.

Abstract: Methods and compositions including introducing a lost circulation material to a zone of interest in a subterranean formation via a wellbore, the zone of interest comprising depleted zones, zones of low pressure, lost circulation zones, fractured zones, and any combination thereof; wherein the lost circulation material comprises an epoxidized linear ?-olefin; a surfactant; a curing agent; and a carbon dioxide gas-generating compound comprising sodium bicarbonate; heating the lost circulation material; and allowing the epoxidized linear ?-olefin to polymerize to a resin and the carbon dioxide gas-generating compound to produce a gas to form a foamed resin in the zone of interest, thereby mitigating a flow of fluids from the wellbore into the subterranean formation.

Abstract: Methods and compositions including introducing a lost circulation material to a zone of interest in a subterranean formation via a wellbore, the zone of interest comprising depleted zones, zones of low pressure, lost circulation zones, fractured zones, and any combination thereof; wherein the lost circulation material comprises: an epoxidized linear ?-olefin; a surfactant; a curing agent; and a nitrogen gas-generating compound, the nitrogen gas-generating compound comprising azodicarbonamide, isocyanate, hydrazine, azobisisobutyronitrile, and any combination thereof; heating the lost circulation material; and allowing the epoxidized linear ?-olefin to polymerize to a resin and the nitrogen gas-generating compound to produce a gas to form a foamed resin in the zone of interest, thereby mitigating a flow of fluids from the wellbore into the subterranean formation.

Abstract: A method for mitigating loss circulation zones in a wellbore is provided. The method includes synthesizing a carbamate from an amine-curing agent, and the carbamate is mixed with an epoxy resin from the loss control composition. Chapter loss control composition is pumped into a wellbore with a loss circulation zone, wherein the loss control composition flows into the loss circulation zone. The carbamate of the loss control composition is allowed to decompose at wellbore temperatures, wherein the carbamate releases CO2 gas and the amine-curing agent. The CO2 gas foams the epoxy resin, expanding the epoxy resin to fill voids in the loss circulation zone, and the amine-curing agent cures the foamed epoxy resin, forming a loss control material that seals the loss circulation zone.

Abstract: Methods for making and using an invert-emulsion drilling fluid, and the invert-emulsion drilling fluid are provided. An exemplary invert-emulsion drilling fluid includes a C-36 dimer diamine dihydrochloride salt (CDDH), an aqueous solvent, a non-aqueous solvent, an emulsifier, and calcium chloride.