Abstract: In some embodiments, a distributed nondestructive inspection method for slickline cable structural defect detection transmits a light pulse along an optical waveguide in the slickline cable. A reflected light signal is 5 received from the optical waveguide in response to the light pulse. Defects can then be determined in the slickline cable based on variations in scattering intensity, phase shift, specific spectral signature, power spectral density, strain amplitude, and/or transmission loss of the reflected light signal as compared to the light pulse.

Abstract: An example telemetry system for downhole operations in a subterranean formation comprises an electromagnetic (EM) radiation source and an EM radiation detector. A waveguide may be coupled to the EM radiation source and the EM radiation detector. A frequency multiplier may be coupled to the waveguide and positioned within a borehole in the subterranean formation.

Abstract: A disclosed system for determining sources of water in a downhole fluid includes one or more downhole sensors that measure at least one analyte concentration in the downhole fluid, and a computer having analyte concentration characteristics for water from multiple sources. The computer uses the analyte concentration characteristics and the at least one analyte concentration measurement to determine an amount of water from at least one given source. A described method for determining sources of water in a downhole fluid includes associating with each of multiple sources of water a characteristic concentration of at least one analyte, obtaining measured concentrations of the at least one analyte with one or more downhole sensors, and deriving for at least one source of water a fraction of the downhole fluid attributable to that at least one source. The deriving may also be based upon measurements from distributed pressure and/or temperature sensors.

Abstract: A downhole telemetry system comprises an optical fiber, a downhole signal generator, a downhole amplifier, and a first downhole laser. The downhole signal generator can be in optical communication with the optical fiber to generate a signal to be transmitted along the optical fiber. The downhole amplifier can be in optical communication with the optical fiber to receive the signal from the downhole signal generator. The first downhole laser can be in optical communication with the downhole amplifier to generate a first laser light output to power the downhole amplifier. Additional apparatus, methods, and systems are disclosed.

Abstract: A hybrid fiber optic assembly and system for use in a well, where the system includes a hybrid fiber optic cable with at least a first transmission region and at least a first sensory region as well as an interrogator system coupled to the hybrid fiber optic cable.

Abstract: An optical cable can include one or more graphenic elements disposed about one or more optically transmissive fibers. A graphenic element can be a coating of graphene or amorphous graphite, a ribbon of graphene or amorphous graphite, or fibers of graphene or amorphous graphite. The graphenic element provides a path for electrical conduction while the optically transmissive fiber provides a path for optical transmission. An optical cable as disclosed herein can include a plurality of electrical and optical paths with a much smaller diameter and weight than traditional cables.

Abstract: A quasi-optical waveguide apparatus includes a waveguide having a chamber formed by a substantially cylindrical body and configured to propagate terahertz radiation. A plurality of windows are included wherein each window is coupled to a respective end of the waveguide such that the chamber is substantially sealed from the ambient atmosphere. The plurality of windows are transparent to the terahertz radiation.

Abstract: A system for recording metadata is disclosed. The system includes an acoustic vibration sensing system. The system also includes one or more sensors operable to measure characteristic parameters. The sensors are coupled to the acoustic vibration sensing system and include one or more channels for recording metadata. The system further includes one or more optical modulators. The optical modulators modulate a signal received from the one or more sensors and direct the modulated signal to the acoustic vibration sensing system. The system further includes one or more sources of the metadata coupled to the one or more optical modulators.

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: Method and apparatus are disclosed for use of a fiber-optic sensor loop for use within a wellbore; with a plurality of light sources optically coupled to the fiber-optic sensor loop; at least one electromagnetically sensitized region within the fiber-optic sensor loop; and a plurality of detectors optically coupled to the fiber-optic sensor loop; and using the sensing system to detect changes in a magnetic field within the wellbore.

Abstract: Methods and systems for the use of partially reflective materials and coatings for optical communications in a wellbore environment are provided. In one embodiment, methods for remote communication in a wellbore comprise: positioning an optical fiber in the wellbore, wherein at least a portion of the optical fiber comprises a partially reflective coating; transmitting an output optical signal from an optical source through the optical fiber; and receiving a reflected optical signal from the optical fiber at an optical detector, wherein at least one optical property of the reflected optical signal is indicative of a downhole condition.

Abstract: Downhole slickline cable including a polymer matrix having reinforcing fibers embedded therein. A plurality of integrity-sensing optical fibers are embedded within the polymer composite and extend along an axial length of the downhole slickline cable that enables slickline cable structural and mechanical integrity self-diagnosis. The cable may include energy transmission lines that include one or more integrity-sensing optical fibers.

Abstract: A polymer composite wireline cable comprising: a polymeric matrix material; at least one reinforced fiber embedded in the polymeric matrix material; and at least one optical fiber disposed in the polymeric matrix material, the at least one optical fiber having at least one pair of Bragg grating sensors, wherein one of the pair of Bragg grating sensors is configured to experience loading strain and the other of the pair of Bragg grating sensors is configured not to experience loading strain.

Abstract: A quasi-optical waveguide apparatus includes a waveguide having a chamber formed by a substantially cylindrical body and configured to propagate terahertz radiation. A plurality of windows are included wherein each window is coupled to a respective end of the waveguide such that the chamber is substantially sealed from the ambient atmosphere. The plurality of windows are transparent to the terahertz radiation.

Abstract: A downhole sensing method includes modulating light to form a soliton that propagates through an optical fiber acting as a sensing element that measures a downhole parameter. The method further includes obtaining scattered light created as the soliton propagates through the optic-fiber. The method further includes determining a value for a downhole parameter based on the scattered light, and displaying a representation of the value.

Abstract: An example telemetry system for downhole operations in a subterranean formation comprises an electromagnetic (EM) radiation source and an EM radiation detector. A waveguide may be coupled to the EM radiation source and the EM radiation detector. A frequency multiplier may be coupled to the waveguide and positioned within a borehole in the subterranean formation.

Abstract: An optical cable can include one or more graphenic elements disposed about one or more optically transmissive fibers. A graphenic element can be a coating of graphene or amorphous graphite, a ribbon of graphene or amorphous graphite, or fibers of graphene or amorphous graphite. The graphenic element provides a path for electrical conduction while the optically transmissive fiber provides a path for optical transmission. An optical cable as disclosed herein can include a plurality of electrical and optical paths with a much smaller diameter and weight than traditional cables.

Abstract: A system may include a sensor to detect a characteristic of a fluid and output an electrical signal proportional to the characteristic, an acoustic signal generator to output an acoustic signal proportional to the electrical signal, and a signal detection apparatus to generate a signal proportional to the acoustic signal and transmit the signal to a remote location.

Abstract: Systems and methods for correcting chromatic dispersion in a remote distributed sensing application are disclosed. A remote distributed sensing system includes an interrogation subsystem configured to transmit an optical pulse and receive a reflection from the optical pulse. The remote distributed sensing system also includes a transit optical fiber coupled to the interrogation subsystem and having chromatic dispersion of a first slope at a frequency of the optical pulse, and an optical fiber under test being located in a remote location apart from the interrogation subsystem. The remote distributed sensing system additionally includes a chromatic dispersion compensator coupled in-line with at least one of the transit optical fiber and the optical fiber under test to adjust chromatic dispersion on the optical pulse in a direction of a second slope having an opposite sign from the first slope.

Abstract: Systems and methods for determining whether mechanical fatigue exists in a downhole cable using thermally-induced acoustic waves are disclosed herein. A cable fatigue monitoring system includes a thermal source, one or more light sources, one or more photodetector arrays, and a computing system comprising a processor, a memory, and a cable distortion module. The cable distortion module is operable to generate acoustic waves in a cable using the thermal source, direct light from the one or more light sources toward the cable, detect light from the one or more light sources transmitted past the cable at the one or more photodetector arrays, and determine, based on the detected light transmitted past the cable, whether a change in velocity of the acoustic waves has occurred in the cable.