Patent application number | Description | Published |
20100070181 | LATEROLOG SHUNT MEASUREMENT - An apparatus for estimating a property of a formation penetrated by a borehole, the apparatus having: a first electrode and a second electrode configured to couple to a characteristic impedance of a material disposed in the borehole; a third electrode configured with the first electrode to electrically couple to a characteristic impedance of the formation; a circuit element coupled to the first electrode and to the second electrode and having a characteristic impedance; a first sensing circuit coupled to the circuit element and configured to provide a first signal related to the impedance of the borehole material; and a second sensing circuit coupled to the first electrode and the third electrode and configured to provide a second signal related to the characteristic impedance of the formation; wherein the first signal and the second signal are used to estimate the property. A method is also provided. | 03-18-2010 |
20110221442 | TOROID GALVANIC AZIMUTHAL LWD TOOL - An apparatus and method for estimating a parameter of interest of an earth formation, particularly relating to borehole logging methods and apparatuses for estimating electrical resistivity properties using at least one transverse toroid. The apparatus may include one or more transmitters for introducing electrical current to the earth formation. The transverse toroid may detect responsive electric signals from the earth formation at one or more frequencies and provide data from one or more depths of investigation. Further multiple transverse toroids may be used for detecting electric signals from a larger azimuthal range than a single transverse toroid. The method includes steps for using the apparatus to obtain data that may be used to estimate the parameter of interest. | 09-15-2011 |
20120078558 | Triaxial Induction Calibration Without Prior Knowledge of the Calibration Area's Ground Conductivity - Disclosed is a method for determining calibration factors of an induction tool that includes three receiver coils, each having a distinct orientation. The method includes: placing the induction logging tool in a first position at a first height above a surface of the earth; performing a first set of measurements of conductivity using the receiver coils with the induction logging tool in the first position at the first height; placing the induction logging tool in a second position at a second height above the surface of the earth; performing a second set of measurements of conductivity using the receiver coils with the induction logging tool in the second position at the second height; and determining the calibration factors that correct conductivity measurements performed by the induction logging tool in a borehole penetrating the earth using the first and second sets of measurements. | 03-29-2012 |
20120081121 | MULTIPLE DEPTHS OF INVESTIGATION USING TWO PAIRS OF TOROID TRANSMITTERS - An apparatus and method for estimating a parameter of interest of an earth formation, particularly relating to borehole logging methods and apparatuses for estimating electrical resistivity properties at multiple depths of investigation. The apparatus may include two or more transmitters for introducing electrical current to the earth formation. The apparatus may include a controller configured to deliver an electrical signal to the two or more transmitters either simultaneously or sequentially. The controller may deliver an electrical signal to two or more transmitters at the same frequency for estimating depth of investigation. The apparatus may include one or more receivers responsive to electric signals from the earth formation at one or more frequencies to provide data from one or more depths of investigation. The method may include steps for using the apparatus to obtain data that may be used to estimate the parameter of interest. | 04-05-2012 |
20130076526 | SYSTEM AND METHOD FOR CORRECTION OF DOWNHOLE MEASUREMENTS - A system for estimating downhole parameters includes: at least one parameter sensor disposed along a downhole component and configured to measure a parameter of one or more of a borehole and an earth formation and generate parameter data; and a processor in operable communication with the at least one parameter sensor, the processor configured to receive the parameter data and deformation data relating to deformation of the downhole component. The processor is configured to: generate a mathematical model of the downhole component deformation in real time based on pre-selected geometrical data representing the downhole component and the received deformation data; estimate, in real time, an alignment of the at least one parameter sensor relative to at least one of another parameter sensor and a desired alignment; and in response to estimating a misalignment of the at least one parameter sensor, correct the parameter data based on the misalignment. | 03-28-2013 |
20130301388 | MISALIGNMENT COMPENSATION FOR DEEP READING AZIMUTHAL PROPAGATION RESISTIVITY - An apparatus and method for estimating a parameter of interest of an earth formation involving alignment information between receivers and their corresponding oriented transmitters. The method may include generating signals indicative responses to energy transmitted into an earth formation; estimating differences in alignment between transmitters and receivers; using the estimated differences in alignment to compensate for misalignment; and estimating a parameter of interest using the misalignment compensated signals. The apparatus may include a bottom hole assembly with one or more oriented transmitters, one or more oriented receivers, one or more alignment sensors, and at least one processor configured to compensate for misalignment using information about difference in alignment between the at least one oriented transmitter and at least one oriented receiver. | 11-14-2013 |
20130304384 | ACCOUNTING FOR BENDING EFFECT IN DEEP AZIMUTHAL RESISTIVITY MEASUREMENTS USING INVERSION - An apparatus and method for estimating a parameter of interest of an earth formation involving alignment information between non-collocated oriented receivers and their corresponding non-collocated oriented transmitters. The method may include generating signal responses indicative to energy transmitted into an earth formation; estimating differences in alignment between transmitters and receivers; using the estimated differences in alignment to compensate for misalignment; and estimating a parameter of interest using the misalignment compensated signals. The misalignment estimate may include an inversion of at least one measurement from an alignment sensor. The apparatus may include a bottom hole assembly with oriented transmitters, oriented receivers, one or more alignment sensors, and at least one processor configured to compensate for misalignment using information about difference in alignment between at least one oriented transmitter and at least one oriented receiver. | 11-14-2013 |
20160003963 | METHOD AND APPARATUS FOR INVERSION IN DIELECTRIC LOGGING - A method for inverting dielectric logging tool measurement data to estimate an electrical characteristic of an earth formation includes: receiving measurement data from the logging tool having a transmitter antenna and receiver antennas spaced known distances from the transmitter antenna; establishing an equation relating magnetic field measurements made by the receiver antennas to the distances and a wave vector; establishing an error equation that quantifies a difference between the magnetic field measurements made by the receiver antennas to magnetic field measurements made by the receiver antennas that would be obtained with an estimated formation electrical characteristic; calculating an error using the error equation for an initial estimated value of the wave vector that comprises a term having a first number multiplied times a second number of radians to provide a plurality of calculated errors; and determining a minimum error from the plurality of calculated errors to estimate the electrical characteristic. | 01-07-2016 |