Abstract: Electromagnetic field monitoring methods and systems for obtaining data corresponding to subsurface rock formations. An electromagnetic field monitoring system includes an electromagnetic transmitter located downhole in a well bore and configured to radiate electromagnetic radiation into a subsurface formation; a fiber optic cable coupled with a fiber optic interrogator, the at least one fiber optic cable and the interrogator located at the surface; and an array of electromagnetic sensors integrally formed in the fiber optic cable and configured to detect the electromagnetic radiation radiated through the subsurface formation. A method of detecting electromagnetic radiation at the surface of an oil well includes transmitting, from an electromagnetic transmitter, electromagnetic radiation into a subsurface formation; and sensing, from the subsurface formation, electromagnetic radiation at the surface of the oil well.

Abstract: A pressure management device of a drilling system is disclosed. The device includes a housing, a primary bearing package coupled to the housing such that the primary bearing package is not removable from the housing. The primary bearing package is further configured to rotate with respect to the housing. The device also includes a sealing package configured to automatically seal between a drill pipe and the primary bearing package in response to an insertion of the drill pipe through the housing.

Abstract: An example system for detecting mud pump stroke information comprises a distributed acoustic sensing (DAS) data collection system coupled to a downhole drilling system, a stroke detector coupled to a mud pump of the downhole drilling system configured to detect strokes in the mud pump and to generate mud pump stroke information based on the detected strokes, and a fiber disturber coupled to the stroke detector and to optical fiber of the DAS data collection system configured to disturb the optical fiber based on mud pump stroke information generated by the stroke detector. The system further comprises a computing system comprising a processor, memory, and a pulse detection module operable to transmit optical signals into the optical fiber of the DAS data collection system, receive DAS data signals in response to the transmitted optical signals, and detect mud pump stroke information in the received DAS data signals.

Abstract: Fluid densities can be monitored in real-time in a wellbore, such as during downhole stimulation operations, using an acoustic pressure-sensing system. The measured acoustic signal can be used to determine pressure fluctuations of a fluid in non-laminar flow. An estimated density of the fluid can be calculated based on the pressure fluctuations of the fluid and a known flow rate of the fluid. The flow rate of the fluid can be known, such as when being held constant by surface equipment or when measured at the surface.

Abstract: A drilling system includes a string of drill pipe extending into a wellbore from a drilling platform. A Y-block junction is coupled to the string of drill pipe at the drilling platform and provides a pressure housing that defines a first conduit and a second conduit that converges with the first conduit. The pressure housing further defines an outlet configured to be coupled to the string of drill pipe extending into the wellbore. A lubricator is operatively coupled to the Y-block junction at the second conduit, and a cable having one or more optical fibers embedded therein is conveyed into the wellbore within the string of drill pipe via the lubricator and the Y-block junction.

Abstract: In accordance with embodiments of the present disclosure, systems and methods for triggering detonation of a perforating gun via optical signals are provided. An improved laser firing head may be used with an optical cable (e.g., fiber optic cable) run through the wellbore to trigger detonation of a perforating gun in response to an optical signal. The laser firing head may be activated, and the perforating gun fired, upon the application of an optical signal output from the surface and transmitted through the optical cable. The disclosed system using the laser firing head with the optical cable may be impervious to electrical interference, since the laser firing head may only fire the perforating gun when a properly modulated laser or light source is directed down the optical cable for a specific period of time.

Abstract: A system includes a controlled acoustic source. The system also includes distributed acoustic sensors along a conduit. The distributed acoustic sensors obtain acoustic signal measurements as a function of position along the conduit in response to at least one acoustic signal provided by the controlled acoustic source. The system also includes a processing unit that generates an acoustic activity plot or report based on the acoustic signal measurements. The acoustic activity plot or report is used to identify at least one acoustic impedance boundary anomaly as a function of position along the conduit.

Abstract: A downhole system usable with a well string is provided that can include a first resonator positioned on the well string. The system can also include a second resonator positioned to couple with the first resonator by an evanescent field. The second resonator can include a load. Further, the system can include a metamaterial positioned between the first resonator and the second resonator for amplifying or extending a range of the evanescent field.

Abstract: Disclosed are optical computing devices that employ birefringent optical elements configured for use in optical computing devices. One optical computing device includes a polarizer configured to generate at least x polarized light and y polarized light, a birefringent integrated computational element configured to optically interact with a substance and the polarizer, thereby generating optically interacted light, and at least one detector arranged to receive the optically interacted light and generate an output signal corresponding to a characteristic of the substance.

Abstract: An example telemetry signal detection apparatus may include a optical splitter, a light source optically coupled to the optical splitter, and a light detector optically coupled to the optical splitter. The apparatus further may include a reference loop optically coupled to the optical splitter and a sensor loop optically coupled to the reference loop and the optical splitter. The reference loop may be contained within a reference loop enclosure. The sensor loop and reference loop may comprise a zero-area Sagnac loop with folded optical fiber or dual fiber cable configurations.

Abstract: Disclosed are optical computing devices that employ birefringent optical elements configured for use in optical computing devices. One optical computing device includes a polarizer configured to generate at least x polarized light and y polarized light, a birefringent integrated computational element configured to optically interact with a substance and the polarizer, thereby generating optically interacted light, and at least one detector arranged to receive the optically interacted light and generate an output signal corresponding to a characteristic of the substance.

Abstract: A distributed optical fiber sensing system is provided. The system can include an interrogator, a transmission optical fiber, a sensing optical fiber, and a reflector. Each of the transmission optical fiber and the sensing optical fiber includes at least one circulator. The reflector is optically coupled to the transmission optical fiber for sensing separate regions along the sensing optical fiber.

Abstract: An example system for detecting mud pulses may include a distributed acoustic sensing (DAS) data collection system coupled to a downhole drilling system, and an information handling system communicably coupled to the DAS data collection system. The information handling system may include a processor and memory coupled to the processor. The memory may contain a set of instructions that, when executed by the processor, cause the processor to receive quadrature DAS data signals from the DAS data collection system, determine a first template signal associated with mud pulses, transform the determined first template signal into analytic representation form, perform a matched filter operation using the quadrature DAS data signals and the transformed first template signal, and analyze an output signal of the matched filter operation to detect mud pulses in the downhole drilling system.

Abstract: An example system for detecting mud pulses may include a distributed acoustic sensing (DAS) data collection system coupled to a downhole drilling system, and an information handling system communicably coupled to the DAS data collection system. The information handling system may include a processor and memory coupled to the processor. The memory may contain a set of instructions that, when executed by the processor, cause the processor to receive quadrature DAS data signals from the DAS data collection system, determine a first template signal associated with mud pulses, transform the determined first template signal into analytic representation form, perform a matched filter operation using the quadrature DAS data signals and the transformed first template signal, and analyze an output signal of the matched filter operation to detect mud pulses in the downhole drilling system.

Abstract: A downhole system usable with a well string is provided that can include a first resonator positioned on the well string. The system can also include a second resonator positioned to couple with the first resonator by an evanescent field. The second resonator can include a load. Further, the system can include a metamaterial positioned between the first resonator and the second resonator for amplifying or extending a range of the evanescent field.

Abstract: A method and system for distributed acoustic sensing using multimode optical fibers.

Abstract: An acoustic well telemetry system has an acoustic telemetry transducer affixed to an in-well type component and a damper between the transducer and the in-well type component. The damper damps transmission from the in-well type component to the transducer of a specified frequency range. A method includes damping a specified frequency range from transmission from an in-well type component to an acoustic telemetry transducer in a well, and receiving another frequency range outside of the specified frequency range with the transducer.

Abstract: A distributed optical fiber sensing system is provided. The system can include an interrogator, a transmission optical fiber, a sensing optical fiber, and a reflector. Each of the transmission optical fiber and the sensing optical fiber includes at least one circulator. The reflector is optically coupled to the transmission optical fiber for sensing separate regions along the sensing optical fiber.

Abstract: An opto-acoustic subsystem is provided. The subsystem includes an optical transmitter and an actuator device. The optical transmitter can be positioned at a surface of a wellbore. The actuator device can be positioned in the wellbore and can respond to a modulated electrical signal generated from a modulated optical signal received from the optical transmitter by outputting a modulated acoustical signal into an environment of the wellbore.

Abstract: Technologies are described for providing optical analysis systems using an integrated computational element that has a surface patterned to selectively reflect or transmit different wavelengths by differing amounts across a spectrum of wavelengths. In one aspect, a measurement tool contains an optical element including a layer of material patterned so that the optical element selectively transmits or reflects, during operation of the measurement tool, light in at least a portion of a wavelength range by differing amounts, the differing amounts being related to a property of a sample. The wavelength range can include wavelengths in a range from about 0.2 ?m to about 100 ?m. Additionally, the sample can include wellbore fluids and the property of the sample is a property of the wellbore fluids.