Using Plural Fields Patents (Class 324/371)
  • Patent number: 9097101
    Abstract: A system, method and device for interrogating a downhole environment in a borehole beneath a surface includes a source of electromagnetic energy, operable to transmit an electromagnetic signal in the borehole, a sensor module, including a passive resonator having a resonant frequency that varies with changes in the condition in the downhole environment to reflect the electromagnetic signal and generates harmonic frequencies in response to a condition in the downhole environment in the borehole and a detector positionable to receive a returned electromagnetic signal. Embodiments include a filter to pass a harmonic of the resonant frequency of the resonating circuit and circuitry configured and arranged to measure the frequency of the harmonic signal.
    Type: Grant
    Filed: March 29, 2012
    Date of Patent: August 4, 2015
    Assignee: CHEVRON U.S.A INC.
    Inventor: Mitchell Carl Smithson
  • Patent number: 8614578
    Abstract: The present disclosure relates to determining the attenuation of an electromagnetic signal passing through a conductive material. An antenna is provided and placed in relatively close proximity to the conductive material. An alternating current is passed through the antenna and the impedance of the antenna is measured. The attenuation is determined using the measured impedance. A single frequency measurement may be made, or multiple measurements using different frequencies may be made. Grouped parameters based on properties of the material and the frequency of the current are used to relate the coil impedance to the attenuation. A current frequency for which the ratio of the antenna's resistive part of the impedance to the angular frequency of the current is substantially insensitive to at least one of the parameters is preferred.
    Type: Grant
    Filed: December 18, 2009
    Date of Patent: December 24, 2013
    Assignee: Schlumberger Technology Corporation
    Inventors: Guozhong Gao, H. Frank Morrison, Hong Zhang, Richard A. Rosthal, David Alumbaugh, Cyrille Levesque
  • Patent number: 8593147
    Abstract: Systems and methods are disclosed for reducing boundary-related artifacts in logs taken from resistivity logging tools. Such tools often exhibit “horns” at boundaries between formation beds having different resistivities. A boundary indicator signal serves to identify the location of these boundaries. When derived from an azimuthally-sensitive resistivity tool, the bed boundary indicator may have a magnitude and shape that serves to nearly eliminate the horns even in high-dip angle environments. Logs that are processed to eliminate these artifacts are expected to be more accurate and thus easier to interpret.
    Type: Grant
    Filed: August 8, 2007
    Date of Patent: November 26, 2013
    Assignee: Halliburton Energy Services, Inc.
    Inventor: Michael S. Bittar
  • Patent number: 8581594
    Abstract: A microresistivity logging tool includes a monopole current injection electrode and at least first and second pairs of potential electrodes. The tool may further include a controller configured for making microresistivity anisotropy measurements using a single firing of the monopole current injection electrode. The controller may be configured to compute a two-dimensional tensor of the local formation resistivity from a single firing of the monopole current injection electrode. The use of a single firing tends to decrease measurement time, which in turn tends to improved azimuthal sensitivity in microresistivity anisotropy imaging while drilling applications.
    Type: Grant
    Filed: December 30, 2009
    Date of Patent: November 12, 2013
    Assignee: Schlumberger Technology Corporation
    Inventors: Tsili Wang, Christopher C Streinz
  • Patent number: 8508231
    Abstract: A microresistivity logging tool includes a monopole current injection electrode and first and second potential electrodes deployed on a downhole tool body. A controller is configured to apply a high frequency alternating current between the monopole current injection electrode and a return and measure a corresponding AC potential difference between the first and second electrodes.
    Type: Grant
    Filed: December 30, 2009
    Date of Patent: August 13, 2013
    Assignee: Schlumberger Technology Corporation
    Inventor: Tsili Wang
  • Patent number: 7612567
    Abstract: A resistivity imaging device injects currents in two orthogonal directions using two pairs of return electrodes and performing impedance measurements of the buttons placed between the returns.
    Type: Grant
    Filed: April 28, 2008
    Date of Patent: November 3, 2009
    Assignee: Baker Hughes Incorporated
    Inventors: Gregory B. Itskovich, Randy Gold, Alexandre N. Bespalov, Stanislav W. Forgang
  • Patent number: 7474101
    Abstract: A method for interpreting transient electromagnetic survey data includes imparting an electromagnetic field in the Earth's subsurface by passing electric current through a transmitter antenna. The electric current includes switched direct current at a selected switching frequency. Voltages induced in a receiver corresponding to electromagnetic effects induced in the Earth's subsurface are detected. Frequency domain electromagnetic response of the Earth's subsurface is determined from the detected voltages and transient electromagnetic response of the Earth's subsurface is determined from the detected voltages.
    Type: Grant
    Filed: September 12, 2006
    Date of Patent: January 6, 2009
    Assignee: KJT Enterprises, Inc.
    Inventor: Kurt M. Strack
  • Patent number: 7365545
    Abstract: A resistivity imaging device injects currents in two orthogonal directions using two pairs of return electrodes and performing impedance measurements of the buttons placed between the returns.
    Type: Grant
    Filed: December 29, 2005
    Date of Patent: April 29, 2008
    Assignee: Baker Hughes Incorporated
    Inventors: Gregory B. Itskovich, Randy Gold, Alexandre N. Bespalov, Stanislav Forgang
  • Patent number: 7026820
    Abstract: A method and apparatus for minimizing direct coupling between transmitters and receivers on a downhole logging tool are disclosed. One embodiment includes a transmitter, a bucking device, and a plurality of receivers, where signals may be directly coupled from the transmitter into the receivers and signals may be indirectly coupled from the transmitter into the receivers through the formation and borehole environment. The bucking device minimizes the magnitude of the signals that are directly coupled from the transmitter into multiple receivers within the plurality. By varying the current in the bucking device, the bucking device minimizes the magnitude of the directly coupled signal of each receiver in the plurality, and each receiver may utilize a common bucking device.
    Type: Grant
    Filed: November 4, 2003
    Date of Patent: April 11, 2006
    Assignee: Halliburton Energy Services, Inc.
    Inventors: Jiaqi Xiao, Li Gao
  • Patent number: 6765386
    Abstract: A logging tool is disclosed for measuring the resistive anisotropy of formations around a borehole. The logging tool includes a set of electrodes that contact a wall of the borehole. The set of electrodes includes a first pair of current electrodes spaced apart vertically, and a second pair of current electrodes spaced apart horizontally. Between the first and second pair of current electrodes are two or more measurement electrodes that measure a vertical axis voltage difference and a horizontal axis voltage difference caused by currents flowing between the pairs of current electrodes. A resistive anisotropy can be calculated from the measured voltage differences. A third pair of current electrodes oriented perpendicularly with respect to the first and second pair of current electrodes may be provided with corresponding measurement electrodes if it is desired to measure the biaxial resistive anisotropy of the formation.
    Type: Grant
    Filed: April 10, 2002
    Date of Patent: July 20, 2004
    Assignee: Halliburton Energy Services, Inc.
    Inventors: Stanley C. Gianzero, Li Gao
  • Patent number: 6670813
    Abstract: A method is disclosed for generating an image of earth formations penetrated by a wellbore. The method includes generating an initial model of the earth formations using formation resistivity measured by a direct current signal. A response to the initial model of an instrument used to make the direct current resistivity measurements is calculated. The calculated response is compared to the measurements of resistivity. The model is adjusted, and the calculating and comparing are repeated until a difference between the calculated response and measurements reaches a minimum. The adjusted model is refined based on resistivity measurements made using an electromagnetic measuring instrument, and the refined model is constrained using acoustic velocity measurements.
    Type: Grant
    Filed: March 27, 2003
    Date of Patent: December 30, 2003
    Assignee: KJT Enterprises, Inc.
    Inventor: Kurt M. Strack
  • Publication number: 20030197510
    Abstract: A logging tool is disclosed for measuring the resistive anisotropy of formations around a borehole. The logging tool includes a set of electrodes that contact a wall of the borehole. The set of electrodes includes a first pair of current electrodes spaced apart vertically, and a second pair of current electrodes spaced apart horizontally. Between the first and second pair of current electrodes are two or more measurement electrodes that measure a vertical axis voltage difference and a horizontal axis voltage difference caused by currents flowing between the pairs of current electrodes. A resistive anisotropy can be calculated from the measured voltage differences. A third pair of current electrodes oriented perpendicularly with respect to the first and second pair of current electrodes may be provided with corresponding measurement electrodes if it is desired to measure the biaxial resistive anisotropy of the formation.
    Type: Application
    Filed: April 10, 2002
    Publication date: October 23, 2003
    Applicant: Halliburton Energy Services, Inc.
    Inventors: Stanley C. Gianzero, Li Gao
  • Patent number: 6603314
    Abstract: A method of determining resistivity of an earth formation through a conductive wellbore casing. The resistance of conductors within an armored electrical cable for a wellbore sonde is measured and the sonde is inserted into the wellbore. The sonde has a plurality of electrodes at axially spaced apart locations for electrically contacting the casing. A first electrical current is applied between a first electrode and a surface return electrode and a first current amplitude and phase is measured. A second phase shifted electrical current is applied between a second electrode and the surface return electrode and the second current amplitude and phase is measured. A first voltage amplitude and phase between a first pair of electrodes axially disposed between the first and second electrodes is measured, and a second voltage amplitude and phase between a second pair of electrodes axially disposed between the first and second electrodes is measured.
    Type: Grant
    Filed: June 23, 1999
    Date of Patent: August 5, 2003
    Assignee: Baker Hughes Incorporated
    Inventors: Richard J. Kostelnicek, Hans-Martin Maurer
  • Patent number: 6541975
    Abstract: In one embodiment the invention comprises a system for generating an image of an Earth formation surrounding a borehole penetrating the formation. Resistivity of the formation is measured using a DC measurement, and conductivity and resistivity of the formations is measured with a time domain signal or AC measurement. Acoustic velocity of the formation is also measured. The DC resistivity measurement, the conductivity measurement made with a time domain electromagnetic signal, the resistivity measurement made with a time domain electromagnetic signal and the acoustic velocity measurements are combined to generate the image of the Earth formation.
    Type: Grant
    Filed: August 23, 2001
    Date of Patent: April 1, 2003
    Assignee: KJT Enterprises, Inc.
    Inventor: Kurt-Martin Strack
  • Patent number: 6426625
    Abstract: A small diameter tool for measurement of resistivity of geological rock formations, including a complex auxiliary electrode structure which is adjustable in electrode length between deep and shallow mode measurement operations.
    Type: Grant
    Filed: October 10, 2000
    Date of Patent: July 30, 2002
    Assignee: Reeves Wireline Technologies, Ltd.
    Inventors: James Roger Samworth, Hemant Kumar Patel
  • Patent number: 6353322
    Abstract: A method for determining the resistivity of earth formations penetrated by a wellbore. Electrical current is imparted to the wellbore and the earth formations from a first electrode located on a mandrel disposed in the wellbore. The electrical current is returned at a second electrode on the mandrel at a spaced apart location from the first electrode. Voltage differences are measured between a first pair and a second pair of electrodes located on the mandrel between the first and the second electrodes. Circuits used to measure the voltage differences are adjusted until the measured voltage difference between the second pair is substantially the same as the measured voltage difference between the first pair. Then the electrical current is returned to an electrode at the earth's surface or other location distal from the first electrode, and measuring the voltage differences is repeated. A difference of the voltage differences is then calculated.
    Type: Grant
    Filed: June 9, 1998
    Date of Patent: March 5, 2002
    Assignee: Baker Hughes Incorporated
    Inventors: Leonty Abraham Tabarovsky, Gregory Boris Itskovich
  • Patent number: 6191588
    Abstract: The borehole imaging apparatus of the present invention includes a tool having an array of voltage electrode buttons mounted on a non-conductive pad. A current source and a current return are preferably located on the non-conductive pads at opposite ends thereof. The locations of the current source and return are designed to force a current to flow in the formation parallel to the pad face and non-parallel to the formation boundary layers. According to a method of the invention, the voltage difference between a pair of buttons in the array is proportional to the resistivity of the formation bed adjacent to the buttons. The ratio of voltage differences between two nearby pairs of electrode buttons provides a quantitative measurement of the ratio of shallow resistivity. The resolution of the image produced by the new tool is determined only by the spacing of the buttons. The tool according to the invention produces much better images than the prior art tools when used in OBM wells.
    Type: Grant
    Filed: July 15, 1998
    Date of Patent: February 20, 2001
    Assignee: Schlumberger Technology Corporation
    Inventor: Min-Yi Chen
  • Patent number: 5754050
    Abstract: A method and apparatus for evaluating the geometrical characteristics of a well, comprising insertion of a sonde (12) of elongate shape into the well, the sonde including azimuth electrodes (A.sub.azi), an annular current electrode (A.sub.0), and at least one annular current return electrode (A). The annular current electrode (A.sub.0) emits a current I.sub.0, which flows essentially in a column of mud situated inside the well and returns to the annular current return electrodes. Signals induced in response to the current I.sub.0 are measured by the azimuth electrodes from which can be determined the geometrical characteristics of the well. An alternative embodiment includes an apparatus which is symmetrical about the azimuth electrodes.
    Type: Grant
    Filed: October 18, 1996
    Date of Patent: May 19, 1998
    Assignee: Schlumberger Technology Corporation
    Inventors: Jan W. Smits, Jean Claude Trouiller
  • Patent number: 5680049
    Abstract: An apparatus for measuring the resistivity of earth formations penetrated by a wellbore having a conductive conduit. The apparatus includes an elongated sonde mandrel, a plurality of electrodes positioned at axially spaced apart locations along the mandrel, the electrodes being electrically insulated from the mandrel and from each other, the electrodes adapted to electrically contact the conduit and positioned collinearly so that the electrodes contact the conduit when the mandrel is radially displaced towards the wall of the conduit. Some electrodes are for injecting electrical current into the conduit, other electrodes are for measuring voltage drop along the conduit at axially spaced apart locations. The mandrel includes selectively extensible locking arms for urging the mandrel into contact with the conduit. The arms are radially positioned opposite to the electrodes.
    Type: Grant
    Filed: December 11, 1995
    Date of Patent: October 21, 1997
    Assignee: Western Atlas International, Inc.
    Inventors: Robert W. Gissler, Otto Fanini, Jacques Maissa, H. Wade Bullock, Peter Rellinger
  • Patent number: 5543715
    Abstract: A method of determining resistivity of an earth formation penetrated by a wellbore having conductive casing. The preferred embodiment includes inserting a sonde into the wellbore, the sonde having a plurality of electrodes at axially spaced apart locations adapted to electrically contact the casing, applying electrical current between a first and a second one of the electrodes and measuring the current, measuring a first voltage between a first pair of electrodes axially disposed between the first and second electrodes and measuring a second voltage between a second pair of electrodes also axially disposed between the first and second electrodes and disposed externally to the first pair to determine casing resistance in between the pairs of electrodes. A second difference between the first and second voltages is also measured.
    Type: Grant
    Filed: September 14, 1995
    Date of Patent: August 6, 1996
    Assignee: Western Atlas International, Inc.
    Inventors: Bension Singer, Hans M. Maurer, Kurt M. Strack, Otto N. Fanini
  • Patent number: 5075626
    Abstract: Methods of operation of an apparatus having at least two pairs of voltage measurement electrodes vertically disposed in a cased well to measure the resistivity of adjacent geological formations from inside the cased well. During stationary measurements with the apparatus at a fixed vertical depth within the cased well, the invention herein discloses methods of operation which include a measurement step and subsequent first and second compensation steps respectively resulting in improved accuracy of measurement. The invention also discloses multiple frequency methods of operation resulting in improved accuracy of measurement while the apparatus is simultaneously moved vertically in the cased well. The multiple frequency methods of operation disclose a first A.C. current having a first frequency that is conducted from the casing into formation and a second A.C. current having a second frequency that is conducted along the casing.
    Type: Grant
    Filed: November 13, 1989
    Date of Patent: December 24, 1991
    Assignee: ParaMagnetic Logging, Inc.
    Inventor: William B. Vail, III
  • Patent number: 4851781
    Abstract: A method and apparatus investigating a circumferential segment of a borehole with an array of elements, which in effect spatially samples the segment, is described whereby, with a single circumferentially oriented array of spaced-apart elements sufficient overlap can be synthesized so as to reduce artifacts attributable to the spatial sampling. Measurements derived from circumferentially successive elements are combined, such as by summing to establish a desired overlap. In the described embodiment to a single lateral array of small electrodes is used to inject survey currents into the borehole wall and each current is measured. Measurements derived from pairs of successive survey currents are then summed to provide the desired overlap.
    Type: Grant
    Filed: April 22, 1986
    Date of Patent: July 25, 1989
    Assignee: Schlumberger Technology Corporation
    Inventors: Thomas L. Marzetta, Weng C. Chew
  • Patent number: 4686477
    Abstract: A method of identifying complex lithologies of subsurface rock formations includes the excitation of at least a portion of the rock formation with a multi-frequency electric current. The voltage resulting in the rock is measured and the phase and amplitude of such voltage is determined for each of the included frequencies. The resistivities are determined for each of the frequencies and are plotted as a function of frequency. The complex lithology of the rock formation is characterized by such plot.
    Type: Grant
    Filed: September 30, 1985
    Date of Patent: August 11, 1987
    Assignee: Mobil Oil Corporation
    Inventors: Wyatt W. Givens, Edgar A. Bowden
  • Patent number: 4659993
    Abstract: An apparatus and a method are disclosed wherein simultaneous electrical well logs can be made with a plurality of focused currents emitted from a plurality of electrodes located along a single equipotential surface of a housing. The focused currents are generated in response to a single voltage signal from a single power supply connected between the housing and a single current return electrode. A voltage reference is located on a cable which suspends the housing and the current return electrode in a well borehole, and a voltage detection circuit detects a voltage offset between the voltage reference and the housing.
    Type: Grant
    Filed: January 10, 1985
    Date of Patent: April 21, 1987
    Assignee: Halliburton Company
    Inventor: Terry D. Womack
  • Patent number: 4282486
    Abstract: Method and apparatus for reducing the dynamic range of measure signals encountered in simultaneously obtaining two focused logs of formation resistivity with different depths of investigation and means for providing the required electrical connections of the electrode system. The apparatus includes an electrode system having a central electrode, a near and far pair of current electrodes, respectively shortcircuited, and aligned symmetrically on both sides of the central electrode, and a near and far pair of measure electrodes, respectively shortcircuited, and aligned symmetrically between the central electrode and the near pair of current electrodes. A signal detected on the near measure electrode pair at a preselected frequency and a first and second signal are combined to produce first and second combined voltages which are used in the production of a first and second frequency, f.sub.1 and f.sub.2, respectively.
    Type: Grant
    Filed: December 4, 1978
    Date of Patent: August 4, 1981
    Assignee: Dresser Industries, Inc.
    Inventors: Richard B. Culver, Francis X. Bostick