Abstract: A gamma-ray detector comprising: a housing having a window through which gamma rays can enter; the housing comprising; a two-dimensional array of electrically conducting carbon nanotubes, which act as a cathode, on a substrate; a metal plate electrode, which acts as an anode, positioned opposite the substrate so that there is a gap containing a gas between the electrode and the nanotubes; and a voltage source connected to the substrate and the electrode such that when in use the voltage between the substrate and the electrode is maintained below the arc-threshold voltage so that no electric current can flow through the gap between the nanotubes and the electrode; wherein the electrode and the substrate are arranged such that when a gamma ray enters the housing and hits one of the nanotubes a spark discharge is triggered between the nanotubes and the plate electrode creating an electrical current that can be measured.

Abstract: An electro-chemical sensor for methane is described having a catalyst to react methane or other low molecular weight hydrocarbons and a detector to detect the turnover or reaction rate and using such information to determine the concentration of the methane or other low molecular weight species. The sensor is preferably used for measurements in a wellbore.

Abstract: A wavelengths based multiplexer for an optical logging tool method and apparatus comprising a plurality of thin film filter sets and architecture to perform optical wavelength multiplexing without bending an optical fiber within the multiplexer. This enables the multiplexer to be used in a down hole, well logging, tool environment.

Abstract: A proppant consists of a core part and shell of a material different from the material of the core part. The shell comprises a soft material attached rigidly to the core part in such a way that the total surface area of the points where the shell and the core part are joined is less than the surface area of the core part.

Abstract: A wireless electromagnetic telemetry system for broadcasting signals across a bottomhole assembly disposed in a borehole drilled through a subterranean formation includes an insulated gap at a first point in the bottomhole assembly, at least one magnetic field sensor at a second point in the bottomhole assembly which measures a magnetic field, and a circuitry which modulates a voltage across the insulated gap, wherein the voltage creates an axial current along the bottomhole assembly that results in the magnetic field.

Abstract: A subsea communication system includes addressable nodes in a wellbore and addressable nodes on a floor, where the nodes in the wellbore and on the floor are able to communicate wirelessly with each other, such as through a formation.

Abstract: A method of managing a fluid or gas reservoir is disclosed which assimilates diverse data having different acquisition time scales and spatial scales of coverage for iteratively producing a reservoir development plan that is used for optimizing an overall performance of a reservoir.

Abstract: A method for determining an amount of creep for a tool on a cable and positioned in a well at an oilfield. The method includes moving a winch at a surface of the oilfield to effect movement of the tool below the surface in the well. The winch may then be stopped with the tool still in the well, but frequently the tool will continue to move, or “creep”, for some time after the winch is stopped. After the winch is stopped, data may be recorded indicative of movement of the tool. This data may then be used for the determining of the amount of creep.

Abstract: Methods and systems for processing microseismic waveforms. The methods and systems provide determining a measure of waveform fit in the frequency-domain comprising constructing, in the frequency-domain, at least one of an amplitude misfit functional and a cross phase functional between arrivals; and estimating source parameters and/or model parameters.

Abstract: A pressure transducer for high-pressure measurements comprising a housing and a piezoelectric resonator located in the housing, wherein the resonator comprises double rotation cut piezoelectric material configured or designed for vibrating in the fundamental tone of dual modes of the fast and slow thickness-shear vibrations.

Abstract: A drilling system for drilling a borehole in an underground formation, comprises a rotary drill bit, a drilling drive mechanism that is capable of applying both rotating the drill bit and applying an axial force to the drill bit, and a control system that is capable of controlling the drive mechanism so as to control rotation of the drill bit and the axial force applied to the drill bit in order to control the depth of cut created by the drill bit when drilling through the formation. A method of drilling a borehole in an underground formation with a rotary drill bit, comprises applying rotation and an axial force to the drill bit and controlling the rotation and axial force so as to control the depth of cut created by the drill bit when drilling through the formation.

Abstract: A cased hole pressure test tool is used to determine the integrity of cement between two points in a borehole in terms of permeability or transmissibility. The test tool drills at least one probe hole through the casing up to the cement. In one embodiment, two probes are set and the dissipation of a pressure pulse through the cement initiated by the first probe is observed by the second probe. In another embodiment, one probe hole is in hydraulic communication with the borehole fluid and a single offset probe is set in another probe hole. Fluid (water) is then added to the borehole to cause a pressure increase in the borehole fluid. Detection of the pressure increase through the cement by the offset probe is indicative of a loss of hydraulic isolation. Packers may be used to isolate the portion of the borehole under test. A mechanism for generating a pressure pulse of known magnitude is also described.

Abstract: Method and apparatus are disclosed for connecting internal shunt tubes to tubular end components of a sand screen assembly by coupling each end of each shunt tube to ports formed in the tubular end components in an annular space between a base pipe and a filter media using a tubular coupler.

Abstract: To perform distributed sensing with an optical fiber using Brillouin scattering, a light pulse is transmitted into the optical fiber, where the transmitted light pulse has a first frequency. Backscattered light and optical local oscillator light are combined, where the backscattered light is received from the optical fiber in response to the transmitted light pulse, and where the optical local oscillator light has a second frequency. A frequency offset is caused to be present between the first frequency of the transmitted light pulse and the second frequency of the optical local oscillator light, where the frequency offset is at least 1 GHz less than a Brillouin frequency shift of the backscattered light. Spectra representing Stokes and anti-Stokes components of the backscattered light are acquired, where the Stokes and anti-Stokes components are separated by a frequency span that is based on the frequency offset.

Abstract: A method of measuring depth and/or azimuth of logging data, the logging data being related to at least one property of a zone GF, CS, CA surrounding a wellbore and being measured by at least a sensor array SA1D, SA2D, the method comprising the steps of: acquiring and storing a first logging data frame F11, F21 corresponding to a first position of the sensor array, acquiring and storing a second logging data frame F12, F22 corresponding to a second position of the sensor array, the first and second position are such that the second logging data frame F12, F22 overlaps at least partially the first logging data frame F11, F21, comparing the first F11, F21 and second F12, F22 logging data frame, and calculating a relative change in the depth ?DP and/or azimuth ?AZ of logging data measured by the sensor array SA1D, SA2D between the first F11, F21 and second F12, F22 logging data frame.

Abstract: An apparatus for use in a well includes a flow control assembly to control fluid flow in a first zone of the well, where the flow control assembly has a fixed flow control device and an adjustable flow control device that cooperate to control the fluid flow in the first zone.

Abstract: A method for sampling fluid in a subterranean formation includes, reducing a viscosity a fluid, pressurizing a portion of the subterranean formation, and collecting a fluid sample. Specifically, a viscosity of a fluid in a portion of the subterranean formation is reduced and a portion of the subterranean formation is pressurizing by injecting a displacement fluid into the subterranean formation. A sample of the fluid pressurized by the displacement fluid is then collected.

Abstract: An optical sensor for pH is described using a cross-linked network of bisilanes to immobilize a pH sensitive chromophore to a surface potentially exposed to a high pressure, high temperature environment such as wellbore effluents at a downhole location.

Abstract: A rod-based well screen is formed in place on a perforated pipe base by wrapping wire around the pipe base and a plurality of rods located around the outside of the pipe. The wire is welded sequentially to each individual rod as it is wrapped around the pipe. The welding and ground electrodes engage the wire and the rods respectively. The rod engaging ground electrode is positioned a short distance ahead of the wire being wrapped around the rods and the pipe base. The ground electrode includes a plurality of contacts. Each contact is mounted to pivot toward and away from a rod. Springs urge each contact toward a rod to hold the rod against the outside surface of the pipe base and to maintain good electrical contact between the contact and the rod. Each contact has a groove to guide the rod into position for welding to the wire.

Abstract: The invention relates to a method of simulating operations of an oilfield, which has process facilities and wellsite operatively connected, each wellsite having a wellbore penetrating a subterranean formation for extracting fluid from an underground reservoir. The method steps include selecting simulators for modeling the oilfield with at least one of the simulators having functionality to model fluid injection, selectively coupling each of the simulators according to a predefined configuration, and modeling an injection operation of the oilfield by selectively communicating between the simulators.