Patent application number | Description | Published |
20080197851 | Borehole Conductivity Simulator Verification and Transverse Coil Balancing - Calibration of the arrays of a multicomponent induction logging tool is achieved by positioning the tool horizontally above ground. The upper and lower housings of the tool are connected by a borehole conductivity simulator which as a resistance comparable to that of a borehole. Axial and radial positioning of the transmitter coils is done by monitoring outputs at receiver coils to achieve a minimum. | 08-21-2008 |
20080218375 | BANDWIDTH WIRELINE DATA TRANSMISSION SYSTEM AND METHOD - 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. | 09-11-2008 |
20080246486 | Mutual Shielding of Collocated Induction Coils in Multi-Component Induction Logging Instruments - In a multicomponent logging tool, a coil is electrically isolated by open circuiting another, substantially orthogonal coil. | 10-09-2008 |
20080252295 | Detection of Borehole Effects Due to Eccentricity on Induction Instruments with Tilted Transducers - A transverse antenna of an electromagnetic induction measurement is provided with an additional pair of split antennas. The difference in the outputs of this split antennas is indicative of a borehole effect such as eccentering of the tool. | 10-16-2008 |
20080278171 | Two-Axial Pad Formation Resistivity Imager - 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. | 11-13-2008 |
20080297160 | Borehole Conductivity Simulator Verification and Transverse Antenna Balancing - A reactance is introduced into a flow path of axial currents in an induction logging tool. The reactance may be a capacitor or an inductor. A transmitter antenna is operated at a frequency defined by a cutoff frequency related to the reactance. | 12-04-2008 |
20080303525 | SINGLE-DIPOLE HIGH FREQUENCY ELECTRIC IMAGER - A single-dipole sensor for determining an electrical property of an earth formation, includes a pad consisting essentially of a body and at least one small electrode separated from a large electrode by an insulator; wherein an output of the sensor includes a measurement of an electrical signal through the formation for each small electrode. A method for using the sensor is included, as well as a method for providing images of the earth formation. | 12-11-2008 |
20090009174 | Borehole Conductivity Simulator Verification and Transverse Coil Balancing - Calibration of the arrays of a multicomponent induction logging tool is achieved by positioning the tool horizontally above ground. The upper and lower housings of the tool are connected by a borehole conductivity simulator which as a resistance comparable to that of a borehole. Axial and radial positioning of the transmitter coils is done by monitoring outputs at receiver coils to achieve a minimum. | 01-08-2009 |
20090105955 | Sensors For Estimating Properties Of A Core - A method for estimating a property downhole is provided, which, in one aspect, may include receiving a core at a receiving end of a downhole tool while removing a portion of the received core distal from the receiving end of the tool, obtaining measurements by a sensor downhole, and processing the measurements to estimate the property of interest. | 04-23-2009 |
20090143989 | WELLBORE LOGGING PERFORMANCE VERIFICATION METHOD AND APPARATUS - 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 sensor adapted 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 a correction to the data signal according to the measured output characteristic. An instrument and an additional method are provided. | 06-04-2009 |
20090243619 | FOUR-TERMINAL ELECTRIC IMAGER FOR RESISTIVE MUDS WITH LOCALIZED CURRENT CONTROL - An apparatus for imaging a subsurface material traversed by a borehole, the apparatus including an imaging pad deployed by a logging instrument, the pad including a plurality of measuring sets, each measuring set including a first current injector electrode, a second current injector electrode, a pair of sensor electrodes disposed between the first current injector electrode and the second current injector electrode, and an output for coupling to an electronics unit adapted for producing the imaging of the subsurface material. | 10-01-2009 |
20090302854 | Apparatus for Formation Resistivity Imaging in Wells with Oil-Based Drilling Fluids - Sequential measurements are made using a two terminal resistivity imaging device wherein the measure electrodes are activated sequentially with the remaining electrodes in a floating mode. This eliminates the hardware requirements for focusing electrodes, prevents galvanic leakage between proximal electrodes and the effects of mutual coupling between circuits including proximal electrodes. | 12-10-2009 |
20090306896 | Apparatus for Formation Resistivity Imaging in Wells with Oil-Based Drilling Fluids - Sequential measurements are made using a two terminal resistivity imaging device wherein the measure electrodes are activated sequentially with the remaining electrodes in a floating mode. This eliminates the hardware requirements for focusing electrodes, prevents galvanic leakage between proximal electrodes and the effects of mutual coupling between circuits including proximal electrodes. | 12-10-2009 |
20100019771 | Multi-Resolution Borehole Resistivity Imaging - 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. | 01-28-2010 |
20100023268 | Multi-resolution Borehole Resistivity Imaging - 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. | 01-28-2010 |
20100052687 | High Resolution Resistivity Earth Imager - 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. | 03-04-2010 |
20100052690 | Formation Resistivity Imaging in Conductive Boreholes - 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. | 03-04-2010 |
20110001481 | Borehole Effect Reduction in Multi-Axial Induction - 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. | 01-06-2011 |
20110025336 | Method and apparatus for well logging resistivity image tomography - 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°) 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. | 02-03-2011 |
20110035153 | WELLBORE LOGGING PERFORMANCE VERIFICATION METHOD AND APPARATUS - 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. | 02-10-2011 |
20110227580 | METHOD FOR MITIGATING LEAKAGE CURRENTS - 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. | 09-22-2011 |
20120074946 | Active Standoff Compensation in Measurements with Oil-Based Mud Resistivity Imaging Devices - 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. | 03-29-2012 |
20120299595 | HIGH RESOLUTION RESISTIVITY EARTH IMAGER - 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. | 11-29-2012 |
20130030708 | WELLBORE LOGGING PERFORMANCE VERIFICATION METHOD AND APPARATUS - A method for correcting a measurement of a property of a subsurface material includes: selecting an instrument having a test circuit and a separate sensor, the test circuit configured for generating a test signal having a characteristic that mimics a downhole measurement environment to generate correction information. The sensor is configured for: transmitting a 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. The sensor is further configured for: receiving the test 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. | 01-31-2013 |
20130063150 | CONNECTION METHOD OF REPLACEABLE SENSORS FOR RESISTIVITY ARRAYS - 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. | 03-14-2013 |
20140111212 | FORMATION RESISTIVITY IMAGING IN CONDUCTIVE BOREHOLES - 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. | 04-24-2014 |
20140182842 | METHOD OF INJECTION FLUID MONITORING - A method of monitoring an injection substance injected into an injection well penetrating the earth and a method of monitoring an underground reservoir storing a substance introduced through an injection well are described. The methods include disposing a monitoring system in a borehole, both a transmitting and a first receiving portion of the monitoring system being disposed in the borehole. The method of monitoring an injection substance also includes injecting the injection substance into the injection well, and monitoring, using a processor processing the received signal, flow of the injection substance out of the injection well. The method of monitoring an underground reservoir includes injecting the injection substance into the injection well for storage in the underground reservoir, and monitoring, using a processor processing the received signal, boundary conditions surrounding the underground reservoir. | 07-03-2014 |
20140312906 | FRACTAL SHAPED ANTENNA FOR DOWNHOLE LOGGING - An apparatus for estimating a subsurface material property includes: a first energy interface device configured to transmit electromagnetic or electrical energy into the subsurface material; a second energy interface device configured to receive return electromagnetic or electrical energy due to the transmitted electromagnetic or electrical energy interacting with the subsurface material; and a processor configured to estimate the property using a signal received from the second device; wherein at least one of the first energy interface device and the second energy interface device is a fractal-shaped antenna comprising a base motif figure and at least one scaled down replication of the base motif figure, the at least one replication being a change from the base motif by at least one of a linear displacement translation and a rotation, and a position of the replication upon the base motif figure is by at least one of rotation, translation, and stretching. | 10-23-2014 |