Abstract: A surface system for an electromagnetic telemetry remote sensing wireless system includes a surface acquisition system configured to receive wireless signals and a plurality of nodes deployed at Earth's surface in a drilling area. Each of the nodes includes a distinct pair of first and second spaced apart electrodes and is configured to digitize voltage differences between the corresponding first and second electrodes and to wirelessly transmit the digitized voltage differences to the surface acquisition system. The voltage differences include an electromagnetic signal transmitted by a downhole tool deployed in a wellbore in the drilling area.

Abstract: Embodiments of the disclosure can include systems and methods for removing in-situ noise from well logging data. In one embodiment, a method can include acquiring noise-calibration data for a logging tool, (the noise-calibration data including data obtained by the logging tool operating under one or more calibration conditions), generating a noise-signature waveform for the logging tool based at least in part on the noise-calibration data, acquiring logging data from the logging tool (the logging data including data obtained by the logging tool operating in a wellbore under one or more operating conditions), generating, based at least in part on the logging data, an uncorrected logging waveform for the logging tool operating in the wellbore under the one or more operating conditions, and modifying the uncorrected logging waveform based at least in part on the noise-signature waveform to generate a corrected logging waveform for the wellbore.

Abstract: A method for modeling an electromagnetic (EM) telemetry signal includes straightening a well in a model and dividing the well into a plurality of segments. The method also includes determining an electrical current in one or more of the segments when the well is straightened. The method also includes replacing the well with equivalent electrical sources based at least partially upon the electrical current in one or more of the segments. The method also includes bending the well back into its original shape in the model and determining the electrical current in one or more of the segments by projection when the well is back in its original shape. The method also includes summing EM fields for each of the one or more segments to estimate the EM telemetry signal.

Abstract: A method for placement of electrodes includes determining spatial distribution of a signal caused by generating an electromagnetic field in an instrument disposed in drill string used to drill a wellbore. The electromagnetic field comprises encoded measurements from at least one sensor associated with the instrument. Voltages induced by noise are measured across at least one pair of spaced apart electrodes placed at a plurality of positions spaced apart from a surface location of the wellbore. A spatial distribution of noise is estimated using the measured voltages. Positions for placement of at least two electrodes are selected using the spatial distribution of signal and the spatial distribution of noise.

Abstract: A surface system for an electromagnetic telemetry remote sensing wireless system includes a surface acquisition system configured to receive wireless signals and a plurality of nodes deployed at Earth's surface in a drilling area. Each of the nodes includes a distinct pair of first and second spaced apart electrodes and is configured to digitize voltage differences between the corresponding first and second electrodes and to wirelessly transmit the digitized voltage differences to the surface acquisition system. The voltage differences include an electromagnetic signal transmitted by a downhole tool deployed in a wellbore in the drilling area.

Abstract: EM-telemetry remote sensing wireless systems include a plurality of downhole tools in a drilling area, an array of electrodes at the earth's surface, a noise reduction manager, and an acquisition system. Each downhole tool transmits a modulated current into the formation to generate an electromagnetic signal at the earth's surface. The array of electrodes comprises a plurality of nodes. Each node has a plurality of electrodes that receives the signal. The signal received by the node has a signal component from the tool and a noise component from the area. The noise reduction manager has a de-mixing vector that filters the noise component of the signal and increases a signal to noise ratio. The acquisition system located on earth's surface wirelessly receives signal from each node.

Abstract: A method for modeling an electromagnetic (EM) telemetry signal includes straightening a well in a model and dividing the well into a plurality of segments. The method also includes determining an electrical current in one or more of the segments when the well is straightened. The method also includes replacing the well with equivalent electrical sources based at least partially upon the electrical current in one or more of the segments. The method also includes bending the well back into its original shape in the model and determining the electrical current in one or more of the segments by projection when the well is back in its original shape. The method also includes summing EM fields for each of the one or more segments to estimate the EM telemetry signal.

Abstract: A method for recovering data from a downhole tool in a wellbore includes measuring an electromagnetic signal using first and second sensors. At least a portion of the electromagnetic signal is transmitted by a downhole tool positioned in a first wellbore. The first and second sensors are each positioned at a different location along a length of a second wellbore. The electromagnetic signal measured by the first and second sensors is decoded to recover a property measured by the downhole tool.

Abstract: A method for placement of electrodes includes determining spatial distribution of a signal caused by generating an electromagnetic field in an instrument disposed in drill string used to drill a wellbore. The electromagnetic field comprises encoded measurements from tromagnetic at least one sensor associated with the instrument. Voltages induced by noise are measured across at least one pair of spaced apart electrodes placed at a plurality of positions spaced apart from a surface location of the wellbore. A spatial distribution of noise is estimated using the measured voltages. Positions for placement of at least two electrodes are selected using the spatial distribution of signal and the spatial distribution of noise.

Abstract: A method for signal communication between a well drilling instrument and the Earths surface includes generating an electromagnetic field in an instrument disposed in drill string used to drill a wellbore. The electromagnetic field includes encoded measurements from at least one sensor associated with the instrument. A signal corresponding to an amplitude and/or phase of the electromagnetic field is measured between the drill string and a surface electrode when the drill string is substantially electrically isolated from a well casing. A signal corresponding to the amplitude and/or phase is measured between the casing and a surface electrode when the casing and the drill string are in electrical contact with each other.

Abstract: EM-telemetry remote sensing wireless systems include a plurality of downhole tools in a drilling area, an array of electrodes at the earth's surface, a noise reduction manager, and an acquisition system. Each downhole tool transmits a modulated current into the formation to generate an electromagnetic signal at the earth's surface. The array of electrodes comprises a plurality of nodes. Each node has a plurality of electrodes that receives the signal. The signal received by the node has a signal component from the tool and a noise component from the area. The noise reduction manager has a de-mixing vector that filters the noise component of the signal and increases a signal to noise ratio. The acquisition system located on earth's surface wirelessly receives signal from each node.

Abstract: Methods and devices for obtaining well log data with reduced coherent noise are provided. One such method may include placing a downhole tool into a well to obtain a set of unfiltered well log data that includes individual measurements obtained at various azimuthal angles within the well. Some of the unfiltered well log data may represent eccentered well log data obtained while the downhole tool is eccentered in the well. The individual measurements of the eccentered well log data may have delays that vary as a function of the azimuthal angle at which they were obtained. By comparing the measurements of the eccentered well log data, a common pattern independent of delay, representing coherent noise, may be identified. The common pattern may be subtracted from the well log data to produce filtered well log data that is less noisy than the unfiltered well log data.

Abstract: A method for recovering data from a downhole tool in a wellbore includes measuring an electromagnetic signal using first and second sensors. At least a portion of the electromagnetic signal is transmitted by a downhole tool positioned in a first wellbore. The first and second sensors are each positioned at a different location along a length of a second wellbore. The electromagnetic signal measured by the first and second sensors is decoded to recover a property measured by the downhole tool.

Abstract: A method for signal communication between a well drilling instrument and the Earths surface includes generating an electromagnetic field in an instrument disposed in drill string used to drill a wellbore. The electromagnetic field includes encoded measurements from at least one sensor associated with the instrument. A signal corresponding to an amplitude and/or phase of the electromagnetic field is measured between the drill string and a surface electrode when the drill string is substantially electrically isolated from a well casing. A signal corresponding to the amplitude and/or phase is measured between the casing and a surface electrode when the casing and the drill string are in electrical contact with each other.

Abstract: A data retrieval device for communicating between a downhole location within a wellbore (16) and a surface location (22) in which a downhole to surface telemetry system is installed and adapted to communicate between a first telemetry module and a second telemetry module with the second telemetry module (18) positioned downhole and connected to a string (12) positioned within the wellbore (16). The data retrieval device is provided with a housing adapted to be positioned inside the string; a communication device supported by the housing; a connection port positioned on the housing and adapted to be connected to a line; and an electronic module supported by the housing. The electronic module is in communication with the communication device and is adapted to store and use at least an identification parameter of the first telemetry module to intercept a signal transmission addressed to the first telemetry module from the second telemetry module (18) via the communication device.

Abstract: An information-carrying acoustic-pressure wave is generated in a wellbore using mud pulse telemetry. The information-carrying acoustic-pressure wave is converted, downhole, into an information-carrying electromagnetic wave and that wave is transmitted to the surface where it is received and the information extracted. A downhole repeater converts the acoustic-pressure wave and transmits the electromagnetic wave. The signal is received by an uphole/surface receiver. The repeater and/or the surface receiver may use an insulating gap. The electromagnetic signal is modeled as a leaky and noisy electronic circuit and the modeling results are used to select a spread spectrum transmission technique. The selected spread spectrum transmission technique is used to transmit the information-carrying electromagnetic signal at an increased rate of data transmission.

Abstract: A disclosed example method involves receiving a first signal transmitted into a reservoir from a production installation in a formation at a wellsite, and determining an apparent resistance of the reservoir based on the first signal. A distance between a fluid extraction tool and a fluid distribution is determined based on the apparent resistance.

Abstract: Embodiments of the disclosure can include systems and methods for removing in-situ noise from well logging data. In one embodiment, a method can include acquiring noise-calibration data for a logging tool, (the noise-calibration data including data obtained by the logging tool operating under one or more calibration conditions), generating a noise-signature waveform for the logging tool based at least in part on the noise-calibration data, acquiring logging data from the logging tool (the logging data including data obtained by the logging tool operating in a wellbore under one or more operating conditions), generating, based at least in part on the logging data, an uncorrected logging waveform for the logging tool operating in the wellbore under the one or more operating conditions, and modifying the uncorrected logging waveform based at least in part on the noise-signature waveform to generate a corrected logging waveform for the wellbore.

Abstract: A disclosed example method involves receiving a first signal transmitted into a reservoir from a production installation in a formation at a wellsite, and determining an apparent resistance of the reservoir based on the first signal. A distance between a fluid extraction tool and a fluid distribution is determined based on the apparent resistance.

Abstract: Methods and devices for obtaining well log data with reduced coherent noise are provided. One such method may include placing a downhole tool into a well to obtain a set of unfiltered well log data that includes individual measurements obtained at various azimuthal angles within the well. Some of the unfiltered well log data may represent eccentered well log data obtained while the downhole tool is eccentered in the well. The individual measurements of the eccentered well log data may have delays that vary as a function of the azimuthal angle at which they were obtained. By comparing the measurements of the eccentered well log data, a common pattern independent of delay, representing coherent noise, may be identified. The common pattern may be subtracted from the well log data to produce filtered well log data that is less noisy than the unfiltered well log data.