A lost circulation material (LCM) is provided having an alkaline nanosilica dispersion and an ester activator. The alkaline nanosilica dispersion and the ester activator may form a gelled solid after interaction over a contact period. Methods of lost circulation control using the LCM are also provided.

A silicon oxide Janus nanosheets relatively permeability modifier (RPM) for carbonate and sandstone formations. The silicon oxide Janus nanosheets RPM may be used to treat a water and hydrocarbon producing carbonate or sandstone formation to reduce water permeability in the formation and increase the production of hydrocarbons. The silicon oxide Janus nanosheets RPM for carbonate formations includes a first side having negatively charged functional groups and a second side having alkyl groups. The silicon oxide Janus nanosheets RPM for sandstone formations includes a first side having positively charged functional groups and a second side having alkyl groups. The negatively charged functional groups may include a negatively charged oxygen group groups and hydroxyl groups. The positively charged functional groups may include amino groups and an amine. Methods of reducing water permeability using the silicon oxide Janus nanosheets RPM and methods of manufacturing the silicon oxide Janus nanosheets RPM are also provided.

A silicon oxide Janus nanosheets relatively permeability modifier (RPM) for carbonate and sandstone formations. The silicon oxide Janus nanosheets RPM may be used to treat a water and hydrocarbon producing carbonate or sandstone formation to reduce water permeability in the formation and increase the production of hydrocarbons. The silicon oxide Janus nanosheets RPM for carbonate formations includes a first side having negatively charged functional groups and a second side having alkyl groups. The silicon oxide Janus nanosheets RPM for sandstone formations includes a first side having positively charged functional groups and a second side having alkyl groups. The negatively charged functional groups may include a negatively charged oxygen group groups and hydroxyl groups. The positively charged functional groups may include amino groups and an amine. Methods of reducing water permeability using the silicon oxide Janus nanosheets RPM and methods of manufacturing the silicon oxide Janus nanosheets RPM are also provided.

A composition includes an aqueous colloidal dispersion of a nanomaterial. The nanomaterial includes, disposed on a surface of the nanomaterial, a first coupling agent including silane and a functional group including an amino acid. The nanomaterial includes, disposed on the surface of the nanomaterial, a second coupling agent including silane and a polymer with a molecular weight between 1,000 and 20,000.

A composition includes an aqueous colloidal dispersion of a nanomaterial. The nanomaterial includes, disposed on a surface of the nanomaterial, a first coupling agent including silane and a functional group including an amino acid. The nanomaterial includes, disposed on the surface of the nanomaterial, a second coupling agent including silane and a polymer with a molecular weight between 1,000 and 20,000.

Provided is a loss circulation material that may consist essentially of an acidic nanosilica dispersion and an activator. The acidic nanosilica dispersion may consist of acidic silica nanoparticles, stabilizer, and water, and may have a pH in a range of 3 to 6. The activator may be one or more from the group consisting of sodium bicarbonate, sodium chloride, or an amine salt. A method is provided for controlling lost circulation in a lost circulation zone in a wellbore comprising introducing the loss circulation material and forming a gelled solid from the loss circulation material in the lost circulation zone.

Disclosed herein is a method of servicing a wellbore penetrating a subterranean formation with a thixotropic cement composition. The thixotropic cement composition comprises a cementitious material, maltodextrin, and an aqueous fluid, has a 10-minute gel strength of from about 30 lbf/100 ft.sup.2 to about 300 lbf/100 ft.sup.2, and can be used to reduce lost circulation in the wellbore. By incorporating maltodextrin into the thixotropic cement composition as disclosed herein, the thixotropic cement composition can have a similar 10-minute gel strength and an increased thickening time when compared to a reference composition.

Disclosed herein is a method of servicing a wellbore penetrating a subterranean formation with a thixotropic cement composition. The thixotropic cement composition comprises a cementitious material, maltodextrin, and an aqueous fluid, has a 10-minute gel strength of from about 30 lbf/100 ft.sup.2 to about 300 lbf/100 ft.sup.2, and can be used to reduce lost circulation in the wellbore. By incorporating maltodextrin into the thixotropic cement composition as disclosed herein, the thixotropic cement composition can have a similar 10-minute gel strength and an increased thickening time when compared to a reference composition.

A composition useful for subterranean water or gas shut off applications includes organosilane-modified colloidal silica and an accelerator. The accelerator includes one or more organic or inorganic salts. A method of using a composition, including an organosilane-modified colloidal silica and an accelerator, includes forming a fluid system that is flowed to a formation in a subterranean zone, such as through a wellbore, where the composition forms a gel to plug the formation and shut off water flow into the wellbore.

A composition useful for subterranean water or gas shut off applications includes organosilane-modified colloidal silica and an accelerator. The accelerator includes one or more organic or inorganic salts. A method of using a composition, including an organosilane-modified colloidal silica and an accelerator, includes forming a fluid system that is flowed to a formation in a subterranean zone, such as through a wellbore, where the composition forms a gel to plug the formation and shut off water flow into the wellbore.