Baker Hughes Corporation

Halliburton Logging Services, Inc.

Halliburton Company

Western Atlas International, Inc.

Baker Hughes, a Ge Compnay, LLC

Baker Hughes Holdings LLC

Randy Gold

Stanislav W Forgang

Alexandre N Bespalov

Gregory Boris Itskovich

Luis M Pelegri

Michael S Crosskno

Carlos A Yanzig

Otto N Fanini

Michael Rabinovich

Leonty Abraham Tabarovsky

Gulamabbas A Merchant

Rashid W Khokhar

Arnold M Walkow

Bill H Corley

Albert A Alexy

James E Brewer

Cynthia Xue

Stephen V Painchaud

Darren E Smith

Zhiyong Jiang

Tsili Wang

Roger W Fincher

Peter S Aronstam

Larry A Watkins

Feyzi Inanc

David R Beard

David M Chace

John W Minear

Homero C Castillo

Sushant Dutta

Richard R Pemper

Babak Kouchmeshky

Mohamed Daoud

Wade D DuPree

Saeed Rafie

Toyli Anniyev

Raman Viswanathan

Allan Jones

Sandeep Gade

Peter John Nolan

David C Rathmann

Dinesh P Shah

Kerry L Sanderlin

Izhar Ahmad

Tammye Crosskno, Legal Representative

A system for performing downhole logging operations includes a conductor coil configured to alternate between producing a magnetic field and measuring a magnetic field induced in a formation, a power supply couplable to the conductor coil for providing an electrical control current to conductor coil, and a signal acquisition system couplable to the conductor coil. The system further includes a permanent magnet coupled to the conductor coil, and a multi-state switch operable in a first state and a second state. In the first state, the conductor coil is coupled to an output of the power supply and decoupled from an input of the signal acquisition system. In the second state, the conductor coil is coupled to the input of acquisition electronics and decoupled from the output of the power supply.

Power-efficient transient electromagnetic evaluation system and method

Estimating parameters of interest of a formation, including density, porosity, and fluid saturation. Methods relate to gamma ray energy spectra calibration for a radiation detector including generating a calibration radiation spectrum using measurements of radiation with the detector in a time interval wherein the radiation comprises predominantly gamma rays emitted by decay of radionuclides produced by neutron activation reactions resulting from neutron irradiation, the time interval following a prior time interval corresponding to thermal neutrons produced from the irradiation; making at least one other radiation measurement with the detector outside the time interval; and producing a calibrated radiation measurement from the at least one other radiation measurement using the calibration radiation spectrum. The measurements may be taken in the time interval by conveying the radiation detector in the borehole at high speed and using a background gate of the detector.

Gamma calibration

An apparatus and method for conducting resistivity logging in a borehole. The apparatus may include a housing configured for fluid isolation, an electrical conductor penetrating the housing and a sealing interface. The apparatus may also include at least one of: an electrical component inside the housing and an electrode disposed on the exterior of the housing. The apparatus is configured to allow the electrical conductor to be moved, while maintaining the sealing interface, between an electrically connected state and an electrically disconnected state with at least one of: the electrical component and the electrode. The method may include using the apparatus for resistivity logging operations.

Connection method of replaceable sensors for resistivity arrays

An apparatus for providing an image of a resistivity property of an earth formation surrounding a borehole is provided. The apparatus, in one aspect, may include a plurality of measure electrodes that are configured to convey an electrical current into the earth formation. In one aspect, each measure electrode may be substantially surrounded by an associated insulator that extends away from a tool body in a manner that blocks at least a portion of a vertical current flowing in a conductive fluid when the tool is operated to log the borehole. A processor provides an image of the resistivity property of the earth formation using the current in plurality of measure electrodes.

Formation resistivity imaging in conductive boreholes

Disclosed is an apparatus for estimating a property of an earth formation penetrated by a borehole having a substantially non-conducting liquid. The apparatus includes: a downhole tool having a transmitter electrode configured to convey an electric current into the earth formation. A measurement electrode is configured to receive the electric current from the earth formation, wherein the electric current bridges as least one of a first gap between the transmitter electrode and the formation and a second gap between the measurement electrode and the formation. A compensating circuit coupling the transmitter electrode to the measurement electrode is configured to reduce a reactive component of a total current received by the measurement electrode. A receiver coupled to the measurement electrode is configured to measure the total current to estimate the property.

Active standoff compensation in measurements with oil-based mud resistivity imaging devices

A suspended well logging device for use in a wellbore drilled in an earthen formation may include a cable configured to be conveyed into the wellbore; a single twisted pair of conductors positioned in the cable; and a conductive armor surrounding the single twisted pair of conductors. In embodiments, the device may further include a first channel formed using the single twisted pair of conductors; a second channel formed using the single twisted pair of conductors and the armor; and a wellbore logging tool coupled to an end of the cable.

Bandwidth wireline data transmission system and method

An apparatus and method for reducing an electric current leakage in a logging tool, particularly relating to reducing electric current leakage by altering a phase difference between a biasing element and an electric current produced by a first power source. The apparatus may include one or more measure electrodes for imparting electric current into a formation, a current meter, at least one current return electrode, a controller, and a biasing element. The method includes adjusting a phase angle difference between the current leaving the measure electrode and a biasing signal applied to the biasing element from a second power source to reduce the current leakage of the apparatus.

Method for mitigating leakage currents

An apparatus, method and computer-readable medium for obtaining a resistivity image of an earth formation. The apparatus includes a downhole assembly configured to be conveyed in a borehole penetrating the earth formation; a plurality of sensor electrodes on the downhole assembly, at least one of the electrodes having a different area than another of the electrodes; and at least one processor configured to: (i) process measurements using each of the sensor electrodes; (ii) process a subset of the measurements substantially unaffected by the different capacitances to produce an image of the borehole wall; and (iii) record the image on a suitable medium.

Multi-resolution borehole resistivity imaging

An apparatus, method and computer-readable medium are provided for estimating a resistivity property of an earth formation. A logging tool includes a first antenna arrangement and a second antenna arrangement of the logging tool; and at least one device for maintaining the first antenna arrangement and the second antenna arrangement in proximity to a wall of the borehole. The first antenna arrangement and the second antenna arrangement may be at substantially the same axial location on the logging tool. Alternately, the first antenna arrangement and the second antenna arrangement may be at different axial positions on the logging tool. Extendible arms of the logging tool are configured to extend one or more of the first antenna arrangement and the second antenna arrangement against a face of the borehole.

Method and apparatus for reducing effect of tool eccentricity in a borehole on multi-axial induction measurements

A method and apparatus for evaluating an earth formation penetrated by a borehole comprises taking resistivity measurements using a plurality of resistivity arrays or pads positioned within the borehole proximal the borehole wall. In one embodiment, pads are spaced apart azimuthally around the perimeter of a tool body, each pad carrying at least one electrode thereon. A sequence of resistivity measurement operations are performed involving sequentially operating each pad, in turn, as a transmitter, with remaining pads and electrodes operated as return electrodes. The sequence preferably involves a succession of adjacent pads around the perimeter of the tool body, resulting in a full rotational (360&#xb0;) imaging of the formation penetrated by the borehole. In one embodiment, the pads include at least two electrodes spaced vertically apart from one another, such that helical current paths are defined between transmitting electrodes and return electrodes.

Method and apparatus for well logging resistivity image tomography

A method for correcting a measurement of a property of a subsurface material includes: selecting an instrument that includes a test circuit and a separate sensor, the test circuit configured for providing a standard for referencing to generate correction information, the sensor configured for: transmitting an electric signal into the subsurface material; and receiving a data signal from the subsurface material; wherein the test circuit and the sensor are switchably coupled to an electronics unit of the instrument; receiving the electric signal from the test circuit in the electronics unit; using the electronics unit, measuring at least one output characteristic of the instrument; and applying the correction information to the data signal according to the measured output characteristic.

Wellbore logging performance verification method and apparatus

A measurement and communication system for use with a tubular string, comprises a tubular string having a plurality of self-powered, autonomous telemetry stations disposed at predetermined locations along the tubular string. Each autonomous telemetry station is adapted to receive at least one first signal and transmit at least one second signal related to the at least one first signal. Power is extracted from potential energy sources proximate each autonomous telemetry station. A method of communicating information along a tubular string comprises, disposing an autonomous telemetry station at predetermined locations along the tubular string. A preferred transmission path is autonomously determined at each of the autonomous telemetry stations. Information is transmitted along the tubular string according to the autonomously determined preferred path.

Apparatus and methods for self-powered communication and sensor network

An imaging tool made includes a pad whose curvature is chosen based on the expected range of borehole radius and the pad size so as to maintain the maximum standoff below a desired value. The curvature may be adjusted using fasteners.

High resolution resistivity earth imager

An apparatus, method and computer-readable medium for evaluating an earth formation are disclosed. The apparatus includes at least one coil on a logging tool conveyed in a borehole in the earth formation. Passage of a current through the coil induces an electrical current in the earth formation. At least two electrodes associated with the logging tool and in proximity to a wall of the borehole have a potential difference in response to the induced electrical current that is indicative of a property of the earth formation. The at least one coil may be mounted on a mandrel of a downhole assembly. The electrodes may be positioned on a first pad extendable from a mandrel of the downhole assembly.

Method and apparatus for resistivity imaging in boreholes with an antenna and two spaced apart electrodes

An apparatus, method and computer-readable medium for obtaining a resistivity image of an earth formation. The apparatus includes a downhole assembly configured to be conveyed in a borehole penetrating the earth formation; a plurality of sensor electrodes on the downhole assembly, each of the plurality of sensor electrodes having a different capacitance to a wall of the borehole; and at least one processor configured to: (i) process measurements using each of the sensor electrodes; (ii) process a subset of the measurements substantially unaffected by the different capacitances to produce an image of the borehole wall; and (iii) record the image on a suitable medium.

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Houston, TX, United States of America

Randy Gold