Abstract: A system includes a drillstring with an electromagnetic (EM) transmitter in a first borehole. The system also includes at least one fiber optic sensor deployed in a second borehole. The system also includes a processor configured to determine a distance or direction of the EM transmitter relative to the at least one fiber optic sensor based on EM field measurements collected by the at least one fiber optic sensor in response to an EM field emitted by the EM transmitter.

Abstract: A through-casing formation monitoring system may include a casing string positioned within a wellbore, a power source electrically coupled to the casing string, a voltage sensor electrically coupled to an inner surface of the casing string such that the voltage sensor allows a continued operation of the wellbore, a fiber optic cable coupled to an electro-optical transducer within the voltage sensor, and an optical interrogation system configured to measure an electric potential applied to the electro-optical transducer via the fiber optic cable.

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: An electromagnetic (EM) telemetry system with capacitive electrodes for use with downhole equipment is described. Embodiments of the EM telemetry system with capacitive electrodes include a downhole transceiver comprising an encoded signal transmitter, a downhole sensor disposed to monitor the downhole equipment, and an encoded signal receiver comprising one or more capacitive counter electrodes. The one or more capacitive counter electrodes receives a first encoded signal from the downhole transceiver, the encoded signal corresponding to a voltage measured between the counter electrode and a wellhead. A decoder and demodulator of the encoded signal receiver recovers information in the first encoded signal. A second encoded signal, which may include instructions for the downhole equipment, may be similarly encoded, modulated, and transmitted from the encoded signal receiver to the downhole transceiver.

Abstract: An electromagnetic (EM) telemetry system with telluric referencing for use with downhole equipment is described. Embodiments of an EM telemetry system with telluric referencing include a downhole transceiver comprising an encoded signal transmitter, a downhole sensor disposed to monitor the downhole equipment, the downhole sensor coupled to the transceiver, an encoded signal receiver, a reference receiver spaced apart from the encoded signal receiver and communicatively coupled to the encoded signal receiver, and a telluric voltage module coupled to one of the encoded signal receiver and the reference receiver. The telluric voltage module is communicatively coupled to the encoded signal receiver and the reference receiver to receive an encoded signal and a reference signal, respectively, which may include telluric noise. The telluric voltage module synchronizes the encoded signal and the reference signal, subtracts the reference signal from the encoded signal, and outputs a signal free from telluric noise.

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 of borehole correction for water-based mud includes conveying an induction logging tool along a borehole through a formation, obtaining one or more formation measurements using the tool, obtaining a water-based mud conductivity, performing an oil-based mud inversion on the formation measurements to determine an inverted formation conductivity, calculating a corrected formation conductivity using the water-based mud conductivity and the inverted formation conductivity, and displaying a log based at least in part on the corrected formation conductivity.

Abstract: A method includes introducing a resistivity logging tool including one or more transmitter coils and one or more receiver coils into a wellbore. First and second signals are then transmitted with a first transmitter coil at first and second frequencies, respectively, and a first receiver coil receives first and second response signals based on the first and second signals. A ratio between the first and second response signals is then calculated to obtain a ratio signal, and the ratio signal is processed in an inversion algorithm. One or more formation characteristics of the subterranean formation may then be determined based on the ratio signal as processed by the inversion algorithm.

Abstract: A method of obtaining an equivalent tool model includes obtaining a set of known well data, in which the known well data includes sensor data measured by a logging tool and an actual dispersion response, and the logging tool has an actual tool size. The method also includes obtaining one or more well parameters from the known well data, and inputting the one or more well parameters and a model tool size into a rigid tool model. The method further includes obtaining an estimated dispersion response from the rigid tool model, and fitting the estimated dispersion response to the actual dispersion response by adjusting the model tool size.

Abstract: Systems and methods are provided for using opto-electrical networks to control downhole electronic devices. A system is provided that can include an optical transmitter. The optical transmitter can generate a first electrical signal associated with a radio frequency or a frequency bandwidth of the radio frequency. The optical transmitter can also convert the first electrical signal to an optical signal. The optical transmitter can further transmit the optical signal over a fiber-optic cable to an optical receiver deployed in a wellbore. The system can include the optical receiver. The optical receiver can convert the optical signal to a second electrical signal associated with the radio frequency or the frequency bandwidth. The optical receiver can also control an electronic device in the wellbore that is identified from the radio frequency or the frequency bandwidth of the second electrical signal.

Abstract: Systems and methods for optimized geosteering using real-time geological models that are updated with LWD measurements containing data such as, for example, layer boundaries and formation properties.

Abstract: An electromagnetic telemetry system can be used for determining a resistivity of a portion of a wellbore drilled through a subterranean formation. For example, the electromagnetic telemetry system can include a computing device and a downhole transceiver positioned on a well tool in the wellbore. The computing device can receive, from the downhole transceiver, a signal indicating a load impedance across an electrically insulating segment of the downhole transceiver. The computing device can determine a resistivity associated with a portion of the wellbore based on the load impedance. The computing device can determine a corrected resistivity by modifying the resistivity associated with the portion of the wellbore using a correction factor.

Abstract: Systems and methods for optimized geosteering using real-time geological models that are updated with LWD measurements containing data such as, for example, layer boundaries and formation properties.

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: An electromagnetic logging tool module includes: a transmitter that sends an electromagnetic transmit signal; a receiver that derives a receive signal from a formation response to a remote module's electromagnetic signal; a processor that processes the receive signal to obtain a measurement of the formation response, wherein the processor demodulates the receive signal to determine the remote module's measurement of a formation response to the electromagnetic transmit signal, and wherein the processor further modulates the electromagnetic transmits signal to share the obtained measurement with the remote module.

Abstract: A substance saturation sensing method includes making a resistivity measurement of a formation proximate to a well with a logging tool prior to installation of a casing string in the well. After the casing string is installed in the well, a first set of measurements of the formation is made with a monitoring system to generate a measured response. A set of calibration values is calculated based on the first set of measurements to produce a resistivity that matches the resistivity measurement. A second set of measurements of the formation is made with the monitoring system during or after saturating of a substance occurs in the formation. At least one parameter indicative of the saturating of the substance in the formation is determined based on the second set of the measurements and the set of calibration values.

Abstract: Systems and methods for active ranging-while-drilling (ARWD) for collision avoidance and/or well interception. A method for ranging while drilling may comprise employing a rotating magnet assembly to induce a changing magnetization and/or electric current in a conductive member disposed in a target wellbore, wherein the rotating magnet assembly may be employed in a second wellbore; measuring at least one component of a magnetic gradient tensor using receivers; and calculating a relative location of the conductive member based at least in part on the measurements of the at least one component of the magnetic gradient tensor.

Abstract: A first transceiver positioned in a wellbore can transmit an electromagnetic signal. The electromagnetic signal can include encoded data. A second transceiver can be positionable at a surface of an adjacent wellbore and can include a computing device communicatively coupled to electrodes positionable in the adjacent wellbore. The electrodes can receive the electromagnetic signal and generate respective voltages in response to the electromagnetic signal. The computing device can determine a decoded version of the encoded data based on a voltage difference between the electrodes.

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 electromagnetic (EM) telemetry system with telluric referencing for use with downhole equipment is described. Embodiments of an EM telemetry system with telluric referencing include a downhole transceiver comprising an encoded signal transmitter, a downhole sensor disposed to monitor the downhole equipment, the downhole sensor coupled to the transceiver, an encoded signal receiver, a reference receiver spaced apart from the encoded signal receiver and communicatively coupled to the encoded signal receiver, and a telluric voltage module coupled to one of the encoded signal receiver and the reference receiver. The telluric voltage module is communicatively coupled to the encoded signal receiver and the reference receiver to receive an encoded signal and a reference signal, respectively, which may include telluric noise. The telluric voltage module synchronizes the encoded signal and the reference signal, subtracts the reference signal from the encoded signal, and outputs a signal free from telluric noise.