Abstract: Formation treatment fluid compositions and methods are provided that include an aqueous base fluid, where the aqueous base fluid comprises one or more salts; and sago. The profile modification fluid may include sago in an amount in the range from 50,000 ppm to 100,000 ppm. Formation treatment fluid compositions may also include an aqueous base fluid, where the aqueous base fluid comprises one or more salts, and sago, where the formation treatment fluid may include sago in an amount in the range from 10,000 ppm to 50,000 ppm. Methods for using the formation treatment fluid may include introducing into a targeted stratum of a subterranean formation a treatment fluid. The subterranean treatment fluid may include an aqueous base fluid, where the aqueous base fluid includes one or more salts, sago, and the treatment fluid may include sago in an amount in the range from 10,000 ppm to 100,000 ppm.

Abstract: A method includes determining a critical micelle concentration (Ccm assumed) of a sample with an unknown concentration (Cs) of a surfactant based on an assumed surfactant concentration (Cassumed) of the sample, providing a benchmark solution with a known concentration of the surfactant, determining an actual critical micelle concentration (Ccm) of the surfactant from the benchmark solution, and calculating the unknown concentration (Cs) of the surfactant in the sample from the following equation: Cs=Ccm/(Ccm assumed/Cassumed).

Abstract: Techniques for analyzing a sample include preparing a sample; circulating a gel solution through the sample to saturate the sample; scanning the saturated sample with a nuclear magnetic resonance (NMR) system to determine two or more NMR values of the saturated sample; determining a permeability of the saturated sample based, at least in part, on the two or more NMR values of the saturated sample; aging the saturated sample; scanning the aged sample with the NMR system to determine two or more NMR values of the aged sample; determining a permeability of the aged sample based, at least in part, on the two or more NMR values of the aged sample; comparing the determined permeability of the saturated sample against the determined permeability of the aged sample; and based on the compared permeabilities, determining a gel solution syneresis rate.

Abstract: A polymer is flowed through a slim tube including porous media until steady state is achieved. A temperature of the porous media with the polymer is adjusted to emulate a reservoir temperature. A slug of a gel solution is flowed through the porous media in the slim tube. The gel solution includes the polymer and a crosslinker. The gel solution is configured to at least partially solidify at the temperature. Multiple pressure drops across the porous media in the slim tube are measured at corresponding locations along a length of the slim tube while the slug flows through the porous media in the slim tube. The slug at least partially solidifies within the slim tube, causing an increase in pressure. A location of gelation of the slug of gel solution within the slim tube is determined based on the increase in pressure.

Abstract: Techniques for analyzing a sample include preparing a sample; circulating a gel solution through the sample to saturate the sample; scanning the saturated sample with a nuclear magnetic resonance (NMR) system to determine two or more NMR values of the saturated sample; determining a permeability of the saturated sample based, at least in part, on the two or more NMR values of the saturated sample; aging the saturated sample; scanning the aged sample with the NMR system to determine two or more NMR values of the aged sample; determining a permeability of the aged sample based, at least in part, on the two or more NMR values of the aged sample; comparing the determined permeability of the saturated sample against the determined permeability of the aged sample; and based on the compared permeabilities, determining a gel solution syneresis rate.

Abstract: A contact angle measurement system includes a housing that can hold a volume of a first fluid having a first density, an adjustable rock sample holder positioned within the housing, a fluid dropper attached to the housing, an image capturing a device, and a computer system. The holder can support a rock sample. An orientation of the holder relative to the housing is adjustable such that an outer surface of the rock sample is at a non-zero angle relative to a lower wall of the housing. When the orientation of the holder relative to the housing is such that the outer surface of the rock sample is at the non-zero angle relative to the lower wall, the fluid droplet traverses the outer surface of the rock sample. The image capturing device can capture images of the fluid droplet as the fluid droplet traverses the outer surface of the rock sample.

Abstract: A contact angle measurement system includes a housing that can hold a volume of a first fluid having a first density, an adjustable rock sample holder positioned within the housing, a fluid dropper attached to the housing, an image capturing a device, and a computer system. The holder can support a rock sample. An orientation of the holder relative to the housing is adjustable such that an outer surface of the rock sample is at a non-zero angle relative to a lower wall of the housing. When the orientation of the holder relative to the housing is such that the outer surface of the rock sample is at the non-zero angle relative to the lower wall, the fluid droplet traverses the outer surface of the rock sample. The image capturing device can capture images of the fluid droplet as the fluid droplet traverses the outer surface of the rock sample.

Abstract: A polymer is flowed through a slim tube including porous media until steady state is achieved. A temperature of the porous media with the polymer is adjusted to emulate a reservoir temperature. A slug of a gel solution is flowed through the porous media in the slim tube. The gel solution includes the polymer and a crosslinker. The gel solution is configured to at least partially solidify at the temperature. Multiple pressure drops across the porous media in the slim tube are measured at corresponding locations along a length of the slim tube while the slug flows through the porous media in the slim tube. The slug at least partially solidifies within the slim tube, causing an increase in pressure. A location of gelation of the slug of gel solution within the slim tube is determined based on the increase in pressure.

Abstract: Techniques for analyzing a sample include preparing a sample; circulating a gel solution through the sample to saturate the sample; scanning the saturated sample with a nuclear magnetic resonance (NMR) system to determine two or more NMR values of the saturated sample; determining a permeability of the saturated sample based, at least in part, on the two or more NMR values of the saturated sample; aging the saturated sample; scanning the aged sample with the NMR system to determine two or more NMR values of the aged sample; determining a permeability of the aged sample based, at least in part, on the two or more NMR values of the aged sample; comparing the determined permeability of the saturated sample against the determined permeability of the aged sample; and based on the compared permeabilities, determining a gel solution syneresis rate.

Abstract: A contact angle measurement system includes a housing that can hold a volume of a first fluid having a first density, an adjustable rock sample holder positioned within the housing, a fluid dropper attached to the housing, an image capturing a device, and a computer system. The holder can support a rock sample. An orientation of the holder relative to the housing is adjustable such that an outer surface of the rock sample is at a non-zero angle relative to a lower wall of the housing. When the orientation of the holder relative to the housing is such that the outer surface of the rock sample is at the non-zero angle relative to the lower wall, the fluid droplet traverses the outer surface of the rock sample. The image capturing device can capture images of the fluid droplet as the fluid droplet traverses the outer surface of the rock sample.