An x-ray-based borehole fluid evaluation tool for evaluating the characteristics of a fluid located external to said tool in a borehole using x-ray backscatter imaging is disclosed, the tool including at least an x-ray source; a radiation shield to define the output faun of the produced x-rays into the borehole fluid outside of the tool housing; at least one collimated imaging detector to record x-ray backscatter images; sonde-dependent electronics; and a plurality of tool logic electronics and power supply units. A method of using an x-ray-based borehole fluid evaluation tool to evaluate the characteristics of a fluid through x-ray backscatter imaging is also disclosed, the method including at least producing x-rays in a shaped output; measuring the intensity of backscatter x-rays returning from the fluid to each pixel of one or more array imaging detectors; and converting intensity data from said pixels into characteristics of the wellbore fluids.

Asphaltene onset pressure of a formation fluid is determined by subjecting the fluid to a plurality of tests where depressurization is conducted at a different depressurization rate for each test while optically monitoring the fluid for asphaltene flocculation. The pressures at which asphaltene flocculation are detected in each test are fit to a curve as a function of depressurization rate, and the curve is extrapolated to a pressure (e.g., 0 psi) to provide the asphaltene onset pressure.

A tool including a dispersive spectrometer deployable within a wellbore is provided. The dispersive spectrometer includes a waveguide layer to detect electromagnetic radiation according to wavelength. The dispersive spectrometer also includes a plurality of detector elements disposed along the waveguide layer to detect electromagnetic radiation associated with a portion of the wavelength of the electromagnetic radiation. A method for using the tool in a subterranean application is also provided.

The subject invention provides compositions and methods for simultaneously enhancing oil recovery, improving the quality of oil and gas through reduction in sulfur-containing compounds, and preventing and/or reducing corrosion of oil and gas production equipment. A multi-functional composition is provided comprising an antimicrobial biosurfactant component, a first ammonium salt, and ammonium hydroxide. In some embodiments, the efficiency of the composition is further enhanced by the addition of a chelating agent, a phenol (e.g., carbolic acid or phenolic acid), and/or an H.sub.2S scavenger. In some embodiments, the composition is further enhanced for use in cold climates by the addition of an antifreeze mixture comprising one or more of a second ammonium salt, sodium chloride and glycerol.

Light from a light source that has interacted with a sample of downhole fluid provided in a downhole optical tool is sequentially passed through a plurality of groups of light filters, each of the groups of light filters including of one or more light filters, to generate a data set for each of the groups of light filters, also referred to as a simultaneous channel group. The data generated for each of the simultaneous channel groups is then analyzed to determine if the data from that simultaneous channel groups is effective in providing information useful for the analysis of the sample of downhole fluid.

The present disclosure describes a method that includes: accessing production logs at a well location of the carbonate reservoir, the production logs comprising data encoding a flow meter profile and a ratio of water and oil (WOR) at each depth of a range of depths; accessing measurements of core samples extracted from each depth within the range of depths; based on the measurements of core samples, determining a relationship of permeability and porosity at each depth within the range of depths; based on the production logs, analyzing the WOR to determine a derivative WOR′ (dWOR/dt) at each depth within the range of depths; and characterizing at least one productive zone at the well location based on a combination of the WOR, the WOR′, the flow meter profile, and the relationship of permeability and porosity at each depth within the range of depths.

A system for controlling a flow of fluid includes a flow control device having a fluid channel configured to transport a fluid between a subterranean region and a borehole conduit, a resonant sensing assembly including a resonator body disposed in fluid communication with the fluid channel, and a controller configured to cause the resonator body to vibrate according to an expected resonance frequency of the resonator body. The system also includes a processing device configured to acquire a measurement signal generated by the resonator body, estimate a property of the fluid based on the measurement signal, and control a flow of the fluid through the flow control device based on the property of the fluid.

Embodiments of the disclosure can include systems, methods, and devices for determining saturation pressure of an uncontaminated fluid. Downhole saturation pressure measurements and downhole OBM filtrate contamination of a contaminated fluid may be obtained and a relationship may be determined between the saturation pressure measurements and OBM filtrate contamination. The relationship may be extrapolated to zero OBM filtrate contamination to determine the saturation pressure of the uncontaminated fluid. In some embodiments, OBM filtrate contamination may be determined from downhole saturation pressure measurements during pumpout of a fluid.

Embodiments of the disclosure can include systems, methods, and devices for determining saturation pressure of an uncontaminated fluid. Downhole saturation pressure measurements and downhole OBM filtrate contamination of a contaminated fluid may be obtained and a relationship may be determined between the saturation pressure measurements and OBM filtrate contamination. The relationship may be extrapolated to zero OBM filtrate contamination to determine the saturation pressure of the uncontaminated fluid. In some embodiments, OBM filtrate contamination may be determined from downhole saturation pressure measurements during pumpout of a fluid.

Methods for determining phase fractions of a downhole fluid via thermal properties of the fluids are provided. In one embodiment, a method includes measuring a temperature of a fluid flowing through a completion string downhole in a well and heating a resistive element of a thermal detector at a position along the completion string downhole in the well by applying power to the resistive element such that heat from the resistive element is transmitted to the fluid flowing by the position. The method also includes determining, via the thermal detector, a flow velocity of the fluid through the completion string and multiple thermal properties of the fluid, and using the determined flow velocity and the multiple thermal properties to determine phase fractions of the fluid. Additional systems, devices, and methods are also disclosed.