Abstract: For determining a water cut of an oil-water mixture produced from an oil well at least one Venturi tube is placed in a well, through which an oil-water mixture, produced from a selected well segment, enters the borehole. During production process, pressure at a Venturi tube inlet and in a Venturi tube throat are measured, and flow temperature of the produced oil-water mixture at the Venturi tube inlet and the temperature of the Venturi tube wall in the Venturi tube throat are measured. Based on the results of the pressure and temperature measurements, the water cut of the oil-water mixture produced from the selected well segment is determined.

Abstract: A method of heterogeneous proppant placement in a subterranean fracture is disclosed. The method comprises injecting well treatment fluid including proppant (16) and proppant-spacing filler material (18) through a wellbore (10) into the fracture (20), heterogeneously placing the proppant in the fracture in a plurality of proppant clusters or islands (22) spaced apart by the material (24), and removing the filler material (24) to form open channels (26) around the pillars (28). The filler material can be dissolvable particles, initially acting as a consolidator during placement of the proppant in the fracture, and later dissolving to leave flow channels between the proppant pillars. The well treatment fluid can include extrametrical materials to provide reinforcement and consolidation of the proppant and, additionally or alternatively, to inhibit settling of the proppant in the treatment fluid.

Abstract: Solid particles are colored with a cationic dye and at least three calibration standards having different known mass concentrations of the colored particles are prepared. A digital analysis of the images of the calibration standards is carried out based on an additive RGB color model and intensity distribution profiles of red, green and blue colors are obtained for each calibration standard. A single norm function is selected to characterize quantitatively changes in the red, green and blue colors in all calibration standards. A single calibration curve is obtained by comparing values of the selected norm function for each calibration standard with a known mass concentration of the colored particles in this calibration standard. A suspension of the colored solid particles is injected through a porous medium sample and the sample is split into two parts along a suspension flow direction.

Abstract: A method of injecting well treatment fluid including proppant and proppant-spacing filler material through a wellbore into the fracture, heterogeneously placing the proppant in the fracture in a plurality of proppant clusters or islands spaced apart by the material, and removing the filler material to form open channels around the pillars for fluid flow from the formation through the fracture toward the wellbore. The proppant and channelant can be segregated within the well treatment fluid, or segregated during placement in the fracture. The filler material can be dissolvable particles, initially acting as a filler material during placement of the proppant in the fracture, and later dissolving to leave the flow channels between the proppant pillars. The well treatment fluid can include extrametrical materials to provide reinforcement and consolidation of the proppant and/or to inhibit settling of the proppant.

Abstract: Solid particles are colored with a cationic dye and at least three calibration standards having different known mass concentrations of the colored particles are prepared. A digital analysis of the images of the calibration standards is carried out based on an additive RGB color model and intensity distribution profiles of red, green and blue colors are obtained for each calibration standard. A single norm function is selected to characterize quantitatively changes in the red, green and blue colors in all calibration standards. A single calibration curve is obtained by comparing values of the selected norm function for each calibration standard with a known mass concentration of the colored particles in this calibration standard. A suspension of the colored solid particles is injected through a porous medium sample and the sample is split into two parts along a suspension flow direction.

Abstract: A suspension of a contaminant comprising at least one solid component and colored with at least one cationic dye is prepared. The suspension is injected through a sample of the porous medium and the sample is then split. A distribution and a profile of the contaminant in the sample is determined on the basis of a distribution and an intensity of the at least one cationic dye.

Abstract: A porous medium sample is initially saturated with a conductive fluid, or a conductive fluid and a non-conductive fluid at the same time, or a non-conductive fluid only. Measurements of electrical resistivity are taken in at least two places along the porous medium sample, and a flooding experiment is carried out with a contaminant solution injected through the porous medium sample. During or after the filtration experiment, second measurements of resistivity are carried out at the same places where the first measurement had been made. Measured data are used for computing a profile of rock saturation with filtrate and a ratio of a modified porosity to an initial porosity of the sample.

Abstract: A method of heterogeneous proppant placement in a subterranean fracture is disclosed. The method comprises injecting well treatment fluid including proppant (16) and proppant-spacing filler material (18) through a wellbore (10) into the fracture (20), heterogeneously placing the proppant in the fracture in a plurality of proppant clusters or islands (22) spaced apart by the material (24), and removing the filler material (24) to form open channels (26) around the pillars (28). The filler material can be dissolvable particles, initially acting as a consolidator during placement of the proppant in the fracture, and later dissolving to leave flow channels between the proppant pillars. The well treatment fluid can include extrametrical materials to provide reinforcement and consolidation of the proppant and, additionally or alternatively, to inhibit settling of the proppant in the treatment fluid.

Abstract: A suspension of a contaminant comprising at least one solid component and colored with at least one cationic dye is prepared. The suspension is injected through a sample of the porous medium and the sample is then split. A distribution and a profile of the contaminant in the sample is determined on the basis of a distribution and an intensity of the at least one cationic dye.

Abstract: A core sample is taken from a wall of a borehole and at least one core fragment is cut from the core sample. The irradiation of the core fragments is carried out with longitudinal acoustic waves and a propagation velocity of the longitudinal acoustic waves in each of the core fragments is measured. An empirical relationship between a velocity of a longitudinal acoustic wave and a porosity for a given lithological type of the rock is selected. A porosity for each core fragment is determined using the measured velocities of the longitudinal acoustic wave and the selected empirical relationship. A value for porosity change is determined by comparing the determined porosity values for the core fragments and a value of a reference porosity typical for the given lithological type of the rock.

Abstract: A method of treating a subterranean formation penetrated by a wellbore is carried out by introducing an emulsion composition into the formation through the wellbore wherein the formation has a formation temperature surrounding the wellbore of at least 120° C. The emulsion composition is formed from an aqueous acid component that forms an internal phase of the emulsion, non-aqueous component that forms an external phase of the emulsion, and a surfactant. The emulsion composition also includes an amount of fibers formed from high temperature polymer material. The high temperature polymer material is characterized by the property of not substantially degrading in water at pH<7 at temperatures below 80° C.

Abstract: A method of heterogeneous proppant placement in a subterranean fracture is disclosed. The method comprises injecting well treatment fluid including proppant (16) and proppant-spacing filler material (18) through a wellbore (10) into the fracture (20), heterogeneously placing the proppant in the fracture in a plurality of proppant clusters or islands (22) spaced apart by the material (24), and removing the filler material (24) to form open channels (26) around the pillars (28). The filler material can be dissolvable particles, initially acting as a consolidator during placement of the proppant in the fracture, and later dissolving to leave flow channels between the proppant pillars. The well treatment fluid can include extrametrical materials to provide reinforcement and consolidation of the proppant and, additionally or alternatively, to inhibit settling of the proppant in the treatment fluid.

Abstract: A source and a receiver of acoustic waves are placed on opposite surfaces of a porous medium sample. A first irradiation of at least one part of the sample with longitudinal acoustic waves is carried out. A propagation velocity of the longitudinal acoustic waves is determined. An empirical relationship between a propagation velocity of a longitudinal acoustic wave and a porosity for a given type of the porous medium based on the porosity and a saturation behavior of the sample is selected. A filtration experiment by injecting a contaminant mud through the sample is carried out. A second irradiation of the same portion of the sample with longitudinal acoustic waves is performed and a propagation velocity of the longitudinal acoustic waves is measured. A porosity change in this part of the sample is determined based on the velocities of the longitudinal acoustic waves measured prior to and after the injection of the contaminant and using the selected empirical relationship.

Abstract: A technique includes completing a well, including installing a tubing string that includes a screen in the well and installing a fiber-based material outside of the screen. The technique further includes using the well as an injection well, including communicating a fluid into the tubing string to cause an injection flow to be communicated in a fluid flow path from an interior of the tubing string, through the screen and into a formation.

Abstract: A method of injecting well treatment fluid including proppant and proppant-spacing filler material through a wellbore into the fracture, heterogeneously placing the proppant in the fracture in a plurality of proppant clusters or islands spaced apart by the material, and removing the filler material to form open channels around the pillars for fluid flow from the formation through the fracture toward the wellbore. The proppant and channelant can be segregated within the well treatment fluid, or segregated during placement in the fracture. The filler material can be dissolvable particles, initially acting as a filler material during placement of the proppant in the fracture, and later dissolving to leave the flow channels between the proppant pillars. The well treatment fluid can include extrametrical materials to provide reinforcement and consolidation of the proppant and/or to inhibit settling of the proppant.

Abstract: A method of treating a subterranean formation penetrated by a wellbore is carried out by introducing an emulsion composition into the formation through the wellbore wherein the formation has a formation temperature surrounding the wellbore of at least 120° C. The emulsion composition is formed from an aqueous acid component that forms an internal phase of the emulsion, non-aqueous component that forms an external phase of the emulsion, and a surfactant. The emulsion composition also includes an amount of fibers formed from high temperature polymer material. The high temperature polymer material is characterized by the property of not substantially degrading in water at pH<7 at temperatures below 80° C.

Abstract: A method of heterogeneous proppant placement in a subterranean fracture is disclosed. The method comprises injecting well treatment fluid including proppant (16) and proppant-spacing filler material (18) through a wellbore (10) into the fracture (20), heterogeneously placing the proppant in the fracture in a plurality of proppant clusters or islands (22) spaced apart by the material (24), and removing the filler material (24) to form open channels (26) around the pillars (28). The filler material can be dissolvable particles, initially acting as a consolidator during placement of the proppant in the fracture, and later dissolving to leave flow channels between the proppant pillars. The well treatment fluid can include extrametrical materials to provide reinforcement and consolidation of the proppant and, additionally or alternatively, to inhibit settling of the proppant in the treatment fluid.

Abstract: Elimination of sand entrainment and a significant increase in hydrodynamic permeability of the sand pack in an area near the wellbore are achieved through the use of a sand and/or proppant, and proppant material mixture at the final stage of the fracture filling process, where individual particles of the proppant material have at least one shape of plates, lattices, hollow bars, inside-hollow tubes with a closed impermeable cavity or cavities, toroidal particles, elongated particles in the form of ovals, pellets or plates, cylinders with a closed impermeable cavity or cavities, or blocks with a comb multi-channel structure with throughout channels of the ellipse or polygon cross-section.

Abstract: This invention relates to the oil and gas industry, in particular, to the technology for preventing proppant/sand entrainment from a reservoir.