Abstract: A method including, without removing a BHA from a wellbore of a well extending into a formation, extending, into an interior flow bore of the BHA, a first component of a wet latch assembly to provide an extended first component of the wet latch assembly, conveying downhole via a wireline cable, from a surface through an interior flow bore provided by a drill string, a second component of the wet latch assembly, and coupling the second component of the wet latch assembly with the extended first component of the wet latch assembly such that an electrical connection is established between the first component and the second component and between the BHA and the surface via the wireline cable, and testing the formation with a formation tester of the BHA, while providing power and/or data telemetry for the formation tester via the wet latch assembly and the wireline cable.

Abstract: A distributed acoustic system (DAS) with an interrogator, an umbilical line attached at one end to the interrogator, and a downhole fiber attached to the umbilical line at the end opposite the interrogator. A method for optimizing a sampling frequency may begin with identifying a length of a fiber optic cable connected to an interrogator, identifying one or more regions on the fiber optic cable in which a backscatter is received, and optimizing a sampling frequency of a distributed acoustic system (DAS) by identifying a minimum time interval that is between an emission of a light pulse such that at no point in time the backscatter arrives back at the interrogator that corresponds to more than one spatial location along a sensing portion of the fiber optic cable.

Abstract: An electromagnetic (EM) telemetry system of a wellbore drilling and production environment includes at least one downhole sensor. The system also includes a downhole transceiver including an encoded signal transmitter. The encoded signal transmitter transmits data collected by the at least one downhole sensor. Further, the system includes an encoded signal receiver, which includes one or more active counter electrodes.

Abstract: A method comprising: without removing a BHA from a wellbore of a well extending into a formation, extending, into an interior flow bore of the BHA, a first component of a wet latch assembly to provide an extended first component of the wet latch assembly; conveying downhole via a wireline cable, from a surface through an interior flow bore provided by a drill string, a second component of the wet latch assembly, and coupling the second component of the wet latch assembly with the extended first component of the wet latch assembly such that an electrical connection is established between the first component and the second component and between the BHA and the surface via the wireline cable; and testing the formation with a formation tester of the BHA, while providing power and/or data telemetry for the formation tester via the wet latch assembly and the wireline cable.

Abstract: A bottom hole assembly (BHA) comprising: a first component of a wet latch assembly, the first component configured for coupling, when extended into the interior flow bore of the BHA, with a second component of the wet latch assembly to provide an assembled wet latch assembly, such that an electrical connection can be made between the first component and the second component; and a formation tester operable for performing a formation test, the formation tester electrically connected with the first component of the wet latch assembly, such that power and/or telemetry can be provided to the formation tester via the assembled wet latch assembly during the formation test.

Abstract: A method for dipole modeling may comprise providing an electromagnetic induction tool comprising an electromagnetic antenna, disposing the electromagnetic induction tool in a wellbore, and activating the electromagnetic antenna. The method may further comprise producing a dipole array equivalent of the electromagnetic antenna, where the dipole array equivalent comprises at least two dipoles. Additionally, the method may comprise implementing the dipole array equivalent in a forward model within an inversion process, wherein the inversion process determines an electromagnetic property.

Abstract: Systems and methods for electromagnetic reservoir monitoring with earth modeling. An electromagnetic (EM) monitoring system for a subterranean earth formation comprises a receiver locatable in a wellbore and responsive to EM radiation propagating through the formation. The receiver generates EM data associated with the formation. The system also comprises a processor that generates a reservoir model of the earth formation based on additional data associated with the formation; converts the reservoir model to a resistivity model of the formation; generates simulated EM data based on the resistivity model of the formation; compares the EM data and the simulated EM data; generates an updated resistivity model based on the comparison between the EM data and the simulated EM data; and determines an operational parameter based on the updated resistivity model to manage production from a well.

Abstract: A system, in some embodiments, comprises: a drill string; a first receiver coil coupled to the drill string at a fixed tilt angle with respect to a longitudinal axis of the drill string; a second receiver coil coupled to the drill string at another fixed tilt angle with respect to the longitudinal axis of the drill string; and a processor coupled to the first and second receiver coils and configured to trigonometrically manipulate a response of the first receiver coil and a response of the second receiver coil to determine a response of a modeled receiver coil having a desired tilt angle with respect to the longitudinal axis of the drill string, wherein said responses are based on a subterranean formation layer.

Abstract: A downhole tool is placed in a borehole of a subsurface formation. The downhole tool comprises a plurality of calipers arranged around a circumference of the downhole tool. A plurality of standoff measurements is received for different rotation angles of the downhole tool, wherein each standoff measurement is indicative of a distance between one of the plurality of calipers and a wall of the borehole. A plurality of apparent diameters of the borehole is determined for the different rotation angles of the downhole tool based on the plurality of standoff measurements and a radius of the downhole tool. A probability function is determined based on the plurality of apparent diameters and at least one of a semiminor axis, semimajor axis, and ellipticity of the borehole is identified based on the probability function.

Abstract: A system includes an electromagnetic logging tool that transmits an electromagnetic signal as the tool is conveyed along a borehole through a formation. The system further includes a processing system that measures a first signal level in response to the tool being at a first measured depth, determines a first conductance based on the first signal level, measures a second signal level in response to the tool being at a second measured depth greater than the first measured depth, the second measured depth and the first measured depth defining a formation interval there between, determines a second conductance based on the second signal level, and assigns a uniform resistivity value to the formation interval based on the first conductance and the second conductance.

Abstract: A distributed acoustic system may comprise an interrogator which includes a single photon detector, an umbilical line comprising a first fiber optic cable and a second fiber optic cable attached at one end to the interrogator, and a downhole fiber attached to the umbilical line at the end opposite the interrogator. A method for optimizing a sampling frequency may comprise identifying a length of a fiber optic cable connected to an interrogator, identifying one or more regions on the fiber optic cable in which a backscatter is received, and optimizing a sampling frequency of a distributed acoustic system by identifying a minimum time interval that is between an emission of a light pulse such that at no point in time the backscatter arrives back at the interrogator that corresponds to more than one spatial location along a sensing portion of the fiber optic cable.

Abstract: An example method for modeling a geological formation includes receiving a set of measurements from an electromagnetic logging tool and representing at least one characteristic of the geological formation as at least one continuous spatial function. At least one coefficient of the at least one continuous spatial function may be determined based, at least in part, on the set of measurements. At least one characteristic of the geological formation may be determined based, at least in part, on the at least one continuous spatial function.

Abstract: A dielectric logging tool for use in a borehole that penetrates a subsurface formation, includes: at least one wall-contacting face with one or more embedded microstrip antennas including a transmit antenna; an oscillator that supplies a transmit signal; a coherent receiver that measures the one or more scattering coefficients; and a processor that derives a formation property from the one or more scattering coefficients. The tool may be conveyed along a borehole, with the scattering coefficients and derived formation property values associated with tool position and orientation to provide a permittivity log.

Abstract: An offshore measured or logging-while drilling electromagnetic telemetry system includes a bottomhole assembly having a transmitter to communicate one or more electromagnetic telemetry signals. A subsea telemetry cable is positioned on a sea floor to receive the telemetry signals. The subsea telemetry cable is coupled to an umbilical cable extending to a surface communication unit positioned at the sea surface. Signals received by the subsea telemetry cable are transmitted to the surface communication unit for further processing.

Abstract: A well monitoring system includes a plurality of transmitter coils coupled to an exterior of a casing positioned within a wellbore, wherein one or more first transmitter coils are positioned at a first location and one or more second transmitter coils are positioned at a second location axially offset from the first location. At least one receiver coil is coupled to the exterior of the casing and positioned at the second location. A power source is communicably coupled to the one or more first and second transmitter coils. The one or more first transmitter coils generates a magnetic field detectable by the at least one receiver coil, and the one or more second transmitter coils generates a bucking signal that minimizes a direct coupling between the one or more first transmitter coils and the at least one receiver coil.

Abstract: A logging tool having a transmitter and receiver is positioned in a geological formation. While the logging tool is static, a transmit input signal is applied to a transmitter to cause the transmitter to induce a transmit output signal in the form of an electromagnetic field into a formation. While the logging tool is static, a formation signal is received based on the transmit output signal. The formation signal may be a voltage indicative of an induced polarization in the formation based on the transmit output signal. A complex resistivity of the formation is determined based on the formation signal.

Abstract: An induction transceiver system includes a magnetic core and an insulator surrounding the magnetic core. The system further includes a cylindrically-shaped sleeve substantially surrounding the insulator. The sleeve includes a gap along the length of the sleeve. A potential difference is measured across the gap when receiving, and a current is applied across the gap when transmitting.

Abstract: Systems, methods and apparatuses for measuring properties of a borehole formation and generating an image of the formation. The method comprises selecting a direction for transmission of an electromagnetic signal, wherein the selection includes altering an electromagnetic coupling between an active element of a first device and at least one passive element of the first device. An electromagnetic signal can be transmitted, by the active element of the first device, into a borehole formation. The electromagnetic signal can subsequently be received by a second device. Formation properties can be determined from the received signal and an image of the formation can be generated.

Abstract: The disclosure relates generally to the inversion of geophysical and/or logging measurements for formation evaluation and monitoring. The disclosure may be related to methods of deconvolution and/or inversion of piecewise formation properties. A method for formation evaluation from a downhole tool may comprise disposing a downhole tool into a wellbore, broadcasting a signal into a formation penetrated by the wellbore, recording the signal from the formation with at least one receiver disposed on the downhole tool, computing an objective function, and determining formation properties by minimizing the objective function.

Abstract: A method includes activating a first electromagnetic source at a first frequency, acquiring a first set of electromagnetic measurements from a first fiber optic electromagnetic sensor in a first well, wherein the first fiber optic electromagnetic sensor is in electromagnetic communication with the first electromagnetic source. The method also includes acquiring a second set of electromagnetic measurements from a second fiber optic sensor in a second well, wherein the second fiber optic sensor is in electromagnetic communication with the first electromagnetic source. The method also includes determining a formation property based on the first set of electromagnetic measurements and the second set of electromagnetic measurements.