Abstract: A method includes positioning a downhole acquisition tool in a wellbore in a geological formation. The method includes operating a pump module to gather information for a fluid outside of the downhole acquisition tool that enters the downhole acquisition tool from a first flowline, a second flowline, or both while the downhole acquisition tool is within the wellbore. Operating the pump module includes controlling a valve assembly to a first valve configuration that enables the fluid to flow into the downhole tool via the first flowline fluidly coupled to a first pump module.

Abstract: A method includes positioning a downhole acquisition tool in a wellbore in a geological formation. The method includes operating a pump module to gather information for a fluid outside of the downhole acquisition tool that enters the downhole acquisition tool from a first flowline, a second flowline, or both while the downhole acquisition tool is within the wellbore. Operating the pump module includes controlling a valve assembly to a first valve configuration that enables the fluid to flow into the downhole tool via the first flowline fluidly coupled to a first pump module.

Abstract: A method includes positioning a downhole acquisition tool in a wellbore in a geological formation. The method includes operating a pump module to gather information for a fluid outside of the downhole acquisition tool that enters the downhole acquisition tool from a first flowline, a second flowline, or both while the downhole acquisition tool is within the wellbore. Operating the pump module includes controlling a valve assembly to a first valve configuration that enables the fluid to flow into the downhole tool via the first flowline fluidly coupled to a first pump module.

Abstract: A method includes operating a downhole acquisition tool in a wellbore in a geological formation. The wellbore or the geological formation, or both, contains a fluid that includes a native reservoir fluid of the geological formation and a contaminant. The method also includes receiving a portion of the fluid into the downhole acquisition tool, obtaining a measured resistivity, a measured conductivity, or both of the portion of the fluid using the downhole acquisition tool, and using a processor of the downhole acquisition tool to obtain a temperature-corrected resistivity, a temperature-corrected conductivity, or both based on a downhole temperature of the portion of the fluid and the measured resistivity, the measured conductivity, or both.

Abstract: A method includes operating a downhole acquisition tool in a wellbore in a geological formation. The wellbore or the geological formation, or both, contain a reservoir fluid. The method also includes receiving a portion of the reservoir fluid into the downhole acquisition tool and performing downhole fluid analysis using the downhole acquisition tool in the wellbore to determine at least one measurement associated with the portion of the reservoir fluid. The at least one measurement includes fluid density, optical density, or both. The method also includes using a processor of the downhole acquisition tool to obtain compressibility of the reservoir fluid based at least in part on the fluid density, the optical density, or both and determining a composition of the reservoir fluid based at least in part on the compressibility.

Abstract: A method includes positioning a downhole acquisition tool in a wellbore in a geological formation. The method includes operating a pump module to gather information for a fluid outside of the downhole acquisition tool that enters the downhole acquisition tool from a first flowline, a second flowline, or both while the downhole acquisition tool is within the wellbore. Operating the pump module includes controlling a valve assembly to a first valve configuration that enables the fluid to flow into the downhole tool via the first flowline fluidly coupled to a first pump module.

Abstract: A method includes operating a downhole acquisition tool in a wellbore in a geological formation. The wellbore or the geological formation, or both, contain a reservoir fluid. The method also includes receiving a portion of the reservoir fluid into the downhole acquisition tool and performing downhole fluid analysis using the downhole acquisition tool in the wellbore to determine at least one measurement associated with the portion of the reservoir fluid. The at least one measurement includes fluid density, optical density, or both. The method also includes using a processor of the downhole acquisition tool to obtain compressibility of the reservoir fluid based at least in part on the fluid density, the optical density, or both and determining a composition of the reservoir fluid based at least in part on the compressibility.

Abstract: A method includes operating a downhole acquisition tool in a wellbore in a geological formation. The wellbore or the geological formation, or both, contains a fluid that includes a native reservoir fluid of the geological formation and a contaminant. The method also includes receiving a portion of the fluid into the downhole acquisition tool, obtaining a measured resistivity, a measured conductivity, or both of the portion of the fluid using the downhole acquisition tool, and using a processor of the downhole acquisition tool to obtain a temperature-corrected resistivity, a temperature-corrected conductivity, or both based on a downhole temperature of the portion of the fluid and the measured resistivity, the measured conductivity, or both.

Abstract: Variable volume systems and methods of use thereof described herein are capable of making calibrated determinations of fluid properties and phase behavior of a fluid sample. The determinations can be calibrated based on one or more calibration functions, such as system volume corrected for pressure and temperature variations. Cross-checking the results of measurements can be used to determine accuracy of the calibration or monitor for leaks or other anomalies of the variable volume systems. The variable volume systems can be implemented in a well logging tool and are capable of being calibrated downhole.

Abstract: A method and apparatus for measuring a presence of a multi-phase system is disclosed. The method includes positioning a fluid communication device of a down hole tool in a well bore, drawing fluid from the well bore to an evaluation cavity and sampling the fluid to determine a presence of a multi-phase system.

Abstract: Methods and apparatus that change the mobility of formation fluids using thermal and non-thermal stimulation including, an example apparatus to simultaneously provide thermal and non-thermal stimulation to change a mobility of a fluid in a subsurface formation includes one or more containers to hold one or more reactants. Additionally, the example apparatus includes a reactor to initiate a chemical reaction with at least one of the reactants. Further, the example apparatus includes an injector to inject a product of the chemical reaction into a formation. The product of the chemical reaction includes heat and a gaseous diluent to change a mobility of a fluid in a subsurface formation.

Abstract: Variable volume systems and methods of use thereof described herein are capable of making calibrated determinations of fluid properties and phase behavior of a fluid sample. The determinations can be calibrated based on one or more calibration functions, such as system volume corrected for pressure and temperature variations. Cross-checking the results of measurements can be used to determine accuracy of the calibration or monitor for leaks or other anomalies of the variable volume systems. The variable volume systems can be implemented in a well logging tool and are capable of being calibrated downhole.

Abstract: Example methods, apparatus and articles of manufacture to process measurements of wires vibrating in fluids are disclosed. A disclosed example apparatus includes a downhole assembly and a surface assembly. The downhole assembly including a sensor to measure a waveform representative of a motion of a wire vibrating within a fluid at a downhole location in a wellbore, a waveform modeler to compute a model parameter from the measured waveform, and a first telemetry module to transmit the computed model parameter to a surface location. The surface assembly including a second telemetry module to receive the computed model parameter from the downhole assembly, and a viscosity analyzer to estimate a viscosity of the fluid from the computed model parameter.

Abstract: A technique involves collecting formation fluids through a single packer having at least one drain located within the single packer. The single packer comprises an outer seal layer, and the at least one drain is positioned in the outer seal layer. A viscosity system also is incorporated and enables the viscosity of a surrounding fluid to be selectively lowered for sampling.

Abstract: Vibrating wire viscometers are disclosed. An example apparatus to determine the viscosity of a downhole fluid is described, the apparatus including a wire to be immersed in a downhole fluid, to vibrate when an alternating current is applied to the wire within a magnetic field, and to generate an electromotive force when vibrating within the magnetic field, the wire comprising a first resistance. The apparatus further includes a nulling circuit coupled to the wire, wherein the nulling circuit comprises a second resistance that is selectable to be substantially equal to the first resistance, and an analyzer coupled to the wire and the nulling circuit to determine the first resistance, the second resistance, and a viscosity of the downhole fluid based on the first and second resistances, at least one characteristic of the wire, and the electromotive force.

Abstract: A technique involves collecting formation fluids through a single packer having at least one drain located within the single packer. The single packer comprises an outer seal layer, and the at least one drain is positioned in the outer seal layer. A viscosity system also is incorporated and enables the viscosity of a surrounding fluid to be selectively lowered for sampling.

Abstract: Vibrating wire viscometers are disclosed. An example apparatus to determine the viscosity of a downhole fluid is described, the apparatus including a wire to be immersed in a downhole fluid, to vibrate when an alternating current is applied to the wire within a magnetic field, and to generate an electromotive force when vibrating within the magnetic field, the wire comprising a first resistance. The apparatus further includes a nulling circuit coupled to the wire, wherein the nulling circuit comprises a second resistance that is selectable to be substantially equal to the first resistance, and an analyzer coupled to the wire and the nulling circuit to determine the first resistance, the second resistance, and a viscosity of the downhole fluid based on the first and second resistances, at least one characteristic of the wire, and the electromotive force.

Abstract: Methods and apparatus to change the mobility of formation fluids using thermal and non-thermal stimulation are described. An example apparatus to simultaneously provide thermal and non-thermal stimulation to change a mobility of a fluid in a subsurface formation includes one or more containers to hold one or more reactants. Additionally, the example apparatus includes a reactor to initiate a chemical reaction with at least one of the reactants. Further, the example apparatus includes an injector to inject a product of the chemical reaction into a formation. The product of the chemical reaction includes heat and a gaseous diluent to change a mobility of a fluid in a subsurface formation.

Abstract: Example methods, apparatus and articles of manufacture to process measurements of wires vibrating in fluids are disclosed. A disclosed example apparatus includes a downhole assembly and a surface assembly. The downhole assembly including a sensor to measure a waveform representative of a motion of a wire vibrating within a fluid at a downhole location in a wellbore, a waveform modeler to compute a model parameter from the measured waveform, and a first telemetry module to transmit the computed model parameter to a surface location. The surface assembly including a second telemetry module to receive the computed model parameter from the downhole assembly, and a viscosity analyzer to estimate a viscosity of the fluid from the computed model parameter.

Abstract: Protective barriers for small devices, such as sensors, actuators, flow control devices, among others, protect the devices from erosive and/or corrosive fluids, for example, formation fluids under harsh downhole conditions. The protective barriers include protective coatings and fluid diverting structures in the fluid flow which facilitate use of the small devices in high temperature-high pressure applications with erosive and/or corrosive fluids that are often found in downhole environments.