Abstract: A method of estimating a directional parameter of a downhole component includes deploying a borehole string in a borehole, the borehole string including the downhole component, the downhole component being rotatable, the downhole component including a gyroscope device and a magnetometer device. The method also includes collecting gyroscope measurement data from the gyroscope device and magnetic field measurement data from the magnetometer device during rotation of the downhole component, and estimating, by a processor, the directional parameter of the downhole component, where the estimating includes correcting the gyroscope measurement data based on the magnetic field measurement data.

Abstract: Systems and methods for measuring a parameter of interest in a borehole in an earth formation are provided. The systems include a downhole sensor having a first sensor component with a first temperature and a second sensor component with a second temperature, the downhole sensor disposed on a downhole component. A temperature control system is configured with a thermal control mechanism operatively connected to at least one of the first and second sensor components. The thermal control mechanism is configured to maintain a temperature difference between the first temperature and the second temperature below a pre-determined temperature difference. The downhole sensor is configured to measure the parameter of interest when the temperature difference is below the pre-determined temperature difference.

Abstract: A method of estimating a directional parameter of a downhole component includes deploying a borehole string in a borehole, the borehole string including the downhole component, the downhole component being rotatable, the downhole component including a gyroscope device and a magnetometer device. The method also includes collecting gyroscope measurement data from the gyroscope device and magnetic field measurement data from the magnetometer device during rotation of the downhole component, and estimating, by a processor, the directional parameter of the downhole component, where the estimating includes correcting the gyroscope measurement data based on the magnetic field measurement data.

Abstract: Systems and methods for measuring a parameter of interest in a borehole in an earth formation are provided. The systems include a downhole sensor having a first sensor component with a first temperature and a second sensor component with a second temperature, the downhole sensor disposed on a downhole component. A temperature control system is configured with a thermal control mechanism operatively connected to at least one of the first and second sensor components. The thermal control mechanism is configured to maintain a temperature difference between the first temperature and the second temperature below a pre-determined temperature difference. The downhole sensor is configured to measure the parameter of interest when the temperature difference is below the pre-determined temperature difference.

Abstract: A method for processing nuclear magnetic resonance (NMR) measurement data includes receiving, with a processor, NMR measurement data obtained from an NMR tool, the NMR measurement data having an echo train affected by a motion artifact, wherein the motion artifact is related to a magnetic field magnitude that varies in a volume of interest due to a motion of the NMR tool. The method further includes reducing, with the processor, an effect on the NMR measurement data of the motion artifact by using a correcting inversion method that models the motion artifact to provide a corrected transverse relaxation time constant (T2) distribution, the correcting inversion method having a multiplicative term having a term that includes at least one local maximum and an optional decay term.

Abstract: Systems, devices and methods for evaluating a volume of interest of an earth formation. The method may include modeling the volume as being in one of two states using a plurality of measurements corresponding to a plurality of measurement types, and may include assigning a relative credence indicator value to each measurement in dependence upon the corresponding measurement value and using the relative credence indicator value for each of the plurality of measurements to estimate the state of the volume by estimating the state of the volume using a state indicator value derived from the relative credence indicator values. The first state of the two states may correspond with presence of a condition associated with the formation, and the second state of the two states may correspond with absence of the condition. The condition may comprise presence of a fluid in the formation having a selected fluid type.

Abstract: A method for processing nuclear magnetic resonance (NMR) measurement data includes receiving, with a processor, NMR measurement data obtained from an NMR tool, the NMR measurement data having an echo train affected by a motion artifact, wherein the motion artifact is related to a magnetic field magnitude that varies in a volume of interest due to a motion of the NMR tool. The method further includes reducing, with the processor, an effect on the NMR measurement data of the motion artifact by using a correcting inversion method that models the motion artifact to provide a corrected transverse relaxation time constant (T2) distribution, the correcting inversion method having a multiplicative term having a term that includes at least one local maximum and an optional decay term.

Abstract: Systems, devices and methods for evaluating a volume of interest of an earth formation. The method may include modeling the volume as being in one of two states using a plurality of measurements corresponding to a plurality of measurement types, and may include assigning a relative credence indicator value to each measurement in dependence upon the corresponding measurement value and using the relative credence indicator value for each of the plurality of measurements to estimate the state of the volume by estimating the state of the volume using a state indicator value derived from the relative credence indicator values. The first state of the two states may correspond with presence of a condition associated with the formation, and the second state of the two states may correspond with absence of the condition. The condition may comprise presence of a fluid in the formation having a selected fluid type.

Abstract: An apparatus for estimating a bubble point of a fluid in an earth formation penetrated by a borehole includes: a pump configured to pump fluid from the earth formation through an extendable probe into a volume; and a processor. The processor is configured to perform a pressure-volume test on the fluid sample. The test includes: increasing the pressure of the fluid sample above formation pressure and logging the pressure and volume of the fluid sample; calculating a reference compressibility of the fluid sample; decreasing the pressure of the fluid sample and logging the pressure and volume; calculating a compressibility of the fluid sample using the logged pressure and volume obtained from during the decreasing; comparing the calculated compressibility to a threshold; and estimating the bubble point as the current fluid sample pressure when the calculated compressibility first meets or exceeds the threshold factor.

Abstract: An apparatus for estimating a bubble point of a fluid in an earth formation penetrated by a borehole includes: a pump configured to pump fluid from the earth formation through an extendable probe into a volume; and a processor. The processor is configured to perform a pressure-volume test on the fluid sample. The test includes: increasing the pressure of the fluid sample above formation pressure and logging the pressure and volume of the fluid sample; calculating a reference compressibility of the fluid sample; decreasing the pressure of the fluid sample and logging the pressure and volume; calculating a compressibility of the fluid sample using the logged pressure and volume obtained from during the decreasing; comparing the calculated compressibility to a threshold; and estimating the bubble point as the current fluid sample pressure when the calculated compressibility first meets or exceeds the threshold factor.

Abstract: An apparatus for controlling fluid flow that includes a chamber having a first valve and a second valve; a sensor that senses a pressure parameter associated with the chamber; and a controller programmed to operate the first valve and the second valve in response to the sensed pressure parameter may be used to control for flow and to obtain data relating to a formation and/or formation fluid.

Abstract: Disclosed is a method for transmitting data from a tool disposed in a borehole penetrating the earth to a receiver. The method includes disposing the tool in a borehole and receiving a series of measurements using a processor disposed at the tool. A telemetry system transmits a latest received measurement that meets acceptance criteria to the receiver after completion of transmission of a previously transmitted measurement.

Abstract: A method for determining a property of a fluid includes: receiving at a computing device an admittance spectrum created by application of an excitation to a resonator contacting the fluid, the spectrum covering a first frequency range and having real and imaginary components; determining a resonant frequency of the admittance spectrum, the resonant frequency being a frequency at which a magnitude of the imaginary component is about zero; determining a bandwidth of the spectrum; and determining the property based on one or both of the resonant frequency and the bandwidth of the resonant frequency.

Abstract: An apparatus for evaluating downhole fluids is disclosed. The apparatus includes: an optical block having an adjustable opening that receives electromagnetic energy emitted by an electromagnetic energy source; a controller operatively associated with the optical block for adjusting the opening size, wherein the opening size is adjusted at least in part based on one or more estimated downhole parameters; and a sensor that receives the electromagnetic energy emitted by the electromagnetic energy source after the emitted electromagnetic energy interacts with a downhole fluid. A method for evaluating downhole fluids is also disclosed.

Abstract: Apparatus and methods for estimating a downhole property are provided. The apparatus may include a downhole tool having a predetermined temperature calibration based at least in part on an expected downhole temperature and a temperature controller in communication with the downhole tool that maintains a downhole tool temperature substantially within the predetermined temperature calibration. A method may include conveying a downhole tool having a predetermined temperature calibration based at least in part on an expected downhole temperature in a well borehole and adjusting the temperature of the downhole tool during downhole operation to maintain a downhole tool temperature substantially within the predetermined temperature calibration.

Abstract: Measurements of fluorescence spectra of fluid samples recovered downhole are processed to give the fluid composition. The processing may include a principal component analysis followed by a clustering method or a neutral network. Alternatively the processing may include a partial least squares regression. The latter can give the analysis of a mixture of three or more fluids.

Abstract: An apparatus for controlling fluid flow that includes a chamber having a first valve and a second valve; a sensor that senses a pressure parameter associated with the chamber; and a controller programmed to operate the first valve and the second valve in response to the sensed pressure parameter may be used to control for flow and to obtain data relating to a formation and/or formation fluid.

Abstract: A method includes calculating a correction factor that uses a tool component volume change model to estimate a system volume change resulting from a change in the tool component. An apparatus includes a carrier conveyable into a well borehole, a formation test tool coupled to the carrier, the formation test tool including a tool component. A measurement device to estimate a change in the tool component during operation, and a compensator uses an estimated system volume change resulting at least in part from the change in the tool component during a downhole operation, the compensator compensating for the system volume change and wherein the estimated system volume change is estimated at least in part using a volume change model.

Abstract: An apparatus for estimating a property of a fluid in an earth formation, the apparatus including: a logging instrument configured to be conveyed in a borehole penetrating the formation; and a plurality of light sources disposed at the logging instrument; wherein each of the light sources is configured to illuminate a sample of the fluid with a light beam causing the sample to fluoresce light with a characteristic related to the property, each of the light sources being configured to provide a light beam with a solid angle and a distance traveled to the sample, the solid angle and the distance being configured to concentrate the beam at an area of the sample that is overlapped substantially a same amount by a beam from another light source in the plurality.

Abstract: Apparatus and methods for estimating a downhole property are provided. The apparatus may include a downhole tool having a predetermined temperature calibration based at least in part on an expected downhole temperature and a temperature controller in communication with the downhole tool that maintains a downhole tool temperature substantially within the predetermined temperature calibration. A method may include conveying a downhole tool having a predetermined temperature calibration based at least in part on an expected downhole temperature in a well borehole and adjusting the temperature of the downhole tool during downhole operation to maintain a downhole tool temperature substantially within the predetermined temperature calibration.