Abstract: Methods and devices used to calibrate EM corrosion detection tools may estimate the effects of the presence of a core on measurements to enable more accurate corrosion detection in the well line. The methods may involve sending voltages to a core of a well tool disposed in the well line to obtain signals while the core is in a saturated and unsaturated state. Subsequent measurements using the core may be calibrated using a constant resulting from the division of the signals achieved at the core in the saturated and unsaturated states.

Abstract: A disclosed downhole drilling system may include a drill bit electrically coupled to a pulse-generating circuit to generate electrical arcs between first and second electrodes during pulsed drilling operations, a sensor to record responses to electromagnetic or acoustic waves produced by the electrical arcs, and a sensor analysis system. The electrical arcs occur at different azimuthal locations between the electrodes. The sensor analysis system may obtain a plurality of measurements representing first responses recorded by the sensor during a pulsed drilling operation, generate a model of a source of the electrical arcs based on the measurements, obtain an additional measurement representing a second response recorded by the sensor during the operation, and determine a characteristic of a formation near the drill bit using an inversion based on the model and the additional measurement. The determined characteristic may be used to determine dip parameters or construct images of the formation.

Abstract: A method for taking measurements in a wellbore including lowering a downhole logging tool in the wellbore; obtaining, via the logging tool, a plurality measurements of a downhole element; processing the plurality of measurements to obtain a plurality of processed measurements; calculating a contour model based on the plurality of processed measurements; and determining a parameter of the downhole element based on the contour model.

Abstract: In accordance with at least one aspect of this disclosure, a signal arithmetic processor includes a fiber optic cable including a fiber optic input and a fiber optic output and two or more electro-optical transducers coupled to the fiber optic cable between the fiber optic input and output and having at least a first electrode and second electrode, the two or more electro-optical transducers configured to modify an optical signal in the fiber optic cable based on a voltage between the first electrode and the second electrode of the two or more electro-optical transducers. The signal arithmetic processor can also include an interferometer coupled to the fiber optic cable and configured to sense a phase difference of a fiber optic signal between the fiber optic input and the fiber optic output.

Abstract: A method and system for visualizing data to detect a collar. A method may comprise disposing an electromagnetic logging tool downhole; emitting an electromagnetic field from the transmitter; energizing a casing with the electromagnetic field to produce an eddy current; recording the eddy current from the casing with the receiver; creating a variable-density-log from the recorded eddy current; selecting a wrapping period for the variable-density-log; creating a wrapped-variable-density-log from the variable-density-log using the wrapping period; and determining at least one collar location and a pipe index with the wrapped-variable-density-log. A system for to detect a collar may comprise an electromagnetic logging tool. The electromagnetic logging tool may comprise a transmitter and a receiver, wherein the transmitter and the receiver may be a coil. The system may further comprise an information handling system.

Abstract: A sensor and sensing method for a downhole logging tool provide an antenna having a toroidal or spiral winding that is toroidally or helically wound around a toroid core. The toroidally-wound toroidal winding antenna forms a natural high-pass filter that is capable of suppressing low-frequency and midrange frequency noise and other interference. This allows the logging tool to sense or detect high-frequency signals, or the high-frequency component of a signal, more clearly and accurately. Multiple toroidally-wound toroidal winding antennas may be used in multiple different configurations, including a multi-axial configuration, bucking configuration, radial configuration, and the like. The sensor and sensing method are particularly useful in applications, such as dielectric logging, short hop communications, waterflood monitoring, and the like.

Abstract: A method of filtering measured responses of downhole pipes, obtained by electromagnetic (EM) logging tools, to correct for natural variations in downhole pipes during downhole pipe defect characterization. A further method of directly characterizing downhole pipe defects by obtaining measured responses at known pipe features, such as casing collars. An apparatus and system for characterizing downhole pipe corrosion is also disclosed.

Abstract: A downhole drilling system is disclosed. The downhole drilling system may include a pulse-generating circuit, a drill bit including a first pair of electrodes electrically coupled to the pulse-generating circuit to receive a first electrical pulse from the pulse-generating circuit and form a first electrical arc between the first pair of electrodes during a pulsed drilling operation; a sensor to record responses to the first electrical pulse during the pulsed drilling operation; and a sensor analysis system communicatively coupled to the sensor, the sensor analysis system configured to obtain a first measurement from the sensor representing the responses recorded by the sensor during the pulsed drilling operation, and determine a first value of the dielectric constant associated with a portion of a formation in proximity to the drill bit, the first value of the dielectric constant based on the first measurement.

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 method and system for wellbore ranging. A method for wellbore ranging may comprise placing a coil antenna in a wellbore, wherein the coil antenna may comprise one or more coil windings, and the coil windings comprise a magnetic material. The method may further comprise measuring a characteristic of an induced electromagnetic field with the coil antenna. A system for wellbore ranging may comprise an electromagnetic ranging tool which may further comprise a coil antenna, wherein the coil antenna comprises one or more coil windings, and wherein the coil windings comprise a magnetic material. The method may further comprise an information handling system, wherein the information handling system may be operable to measure a characteristic of an induced electromagnetic field with the coil antenna.

Abstract: Methods to accurately plan and optimize clamped source excitation in ranging or telemetry operations approximate a well having a complex pipe structure as a simple solid pipe (“effective model”) with an effective pipe cross-section and resistance. The simple solid pipe is then treated as a thin wire and analyzed using a FAST Code.

Abstract: A method for determining tubing permeability includes conveying a tool through a tubular string in a borehole. The tool includes a transmitter that transmits a primary electromagnetic field and a receiver that receives at least one collar response. The collar response includes a secondary electromagnetic field produced in response to the primary field by a collar in the tubular string. The method further includes determining a permeability of at least one portion of the tubular string based on a magnitude of the at least one collar response. The method further includes displaying a representation of the at least one portion of the tubular string based on the permeability.

Abstract: A method for detecting corrosion may comprise placing an electromagnetic logging tool into a wellbore, emitting an electromagnetic field from a transmitter, energizing a casing with the electromagnetic field to produce an eddy current, recording the eddy current from the casing with a receiver, creating a well log from the recorded eddy current, removing a collar signal from the well log to obtain a collar-removed signal, calculating a baseline signal from the collar-removed signal, subtracting the baseline signal from the collar-removed signal to obtain a baseline-subtracted signal, calculating an artifact-removed signal with the baseline-subtracted signal, and displaying the artifact-removed signal. A system for detecting corrosion may comprise an electromagnetic logging tool, wherein the electromagnetic logging tool comprises a transmitter and a receiver. The system may further comprise an information handling system.

Abstract: A method and a system for tuning a pad. The method may comprise disposing a downhole tool into a borehole, configuring the pad in a first configuration, taking a first measurement of the formation in the first configuration, configuring the pad in a second configuration, taking a second measurement of the formation in the second configuration, determining a tuning coefficient to reduce a tool body effect in the first measurement and the second measurement, computing a first weighted measurement from the tuning coefficient and the first measurement, computing a second weighted measurement from the tuning coefficient and the second measurement, and computing a tuned impedance from a ratio of the first weighted measurement and the second weighted measurement. A system for determining a formation boundary may comprise a downhole tool, an arm, and a pad. The system may further comprise a conveyance and an information handling system.

Abstract: Systems and methods for incorporating mandrel current measurements in deep ranging inversion. A method may include introducing a current through a transmitter into a subterranean formation, wherein the transmitter may be a component of an electromagnetic induction tool disposed in a wellbore, wherein the electromagnetic induction tool may comprise the transmitter, a toroid receiver, and a second receiver comprising a coil or electrode, wherein the transmitter, the toroid receiver, and the second receiver may be disposed on a tubular; measuring a first signal utilizing the toroid receiver, wherein the first signal may comprise a tubular current; measuring a second signal utilizing the receiver and determining at least one downhole parameter utilizing the first signal and the second signal.

Abstract: Direct field cancelation with optional receive antenna compensation is provided in at least some gradient induction logging tool embodiments. Illustrative embodiments include a spatial gradient antenna arrangement having multiple spatially-separated multi-component coil antennas and a multi-component coil antenna having bucking coils that cancel the effects of both the direct field and the gradient of the direct field on the receive signal. Other tool embodiments include a multi-component coil antenna and a spatial gradient antenna arrangement having spatially separated multi-component coil antennas with bucking coils that cancel the effects of both the direct field and the gradient of the direct field on the receive signal. Those embodiments employing a spatial gradient antenna arrangement for receiving may further be configured to provide compensated measurements by combining measurements from rotated orientations of the spatial gradient antenna.

Abstract: A method and system for mitigating direct coupling. A method of mitigating direct coupling may comprise disposing an electromagnetic sensor system in a wellbore. The electromagnetic sensor system may include a receiver disposed on a conductive body and a gap sub disposed at another location on the conductive body. Exciting an electromagnetic source to inject an electrical current into a formation. Exciting the gap sub to achieve a small current condition at the selected point. Performing a first measurement at a receiver. Interpreting the first measurement to calculate a formation or pipe parameter and using the formation or pipe parameter to adjust at least one parameter of a well operation. A system of mitigating direct coupling may include a conductive body may comprise a gap sub, a controller, a voltage source, a receiver, and an information handling system. The information handling system may be operable to cancel current.

Abstract: In-well steam monitoring for SAGD operations using permanent fiber optic sensors installed behind the casing of an injector or producer well provides continuous monitoring of downhole steam injection. Using in-well sensor measurements, the system may also adjust or otherwise manipulate the volume of injected steam over time.

Abstract: A method and system for identifying a target well. A system for identifying a target well may comprise placing an electromagnetic ranging tool in a wellbore, transmitting an electromagnetic field into a formation, inducing an eddy current within a target well, measuring a second electromagnetic field from the target well, calculating a position or an orientation of a transmitter or a receiver relative to another position, and calculating at least one parameter of the target well. An electromagnetic ranging system may comprise an electromagnetic ranging tool and an information handling system. The information handling system may be operable to calculate a position and/or an orientation of a transmitter or a receiver relative to another position on the electromagnetic ranging tool disposed on a borehole assembly, and calculate at least one parameter of a target well from the calculated position or orientation of the transmitter and the receiver.