| Entries |
| Document | Title | Date |
|---|
| 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 |
| 20080231283 | Multi-Frequency Cancellation of Dielectric Effect - Measurements made with an induction logging tool are responsive to formation conductivity and permittivity. The effect of permittivity can be substantially removed by multifrequency focusing. | 09-25-2008 |
| 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 |
| 20080265892 | Externally Guided and Directed Field Induction Resistivity Tool - In one aspect an induction resistivity tool incorporated into a downhole tool string comprises an outer wall of a downhole component comprising an outer diameter and at least one induction transmitter assembly disposed along the outer diameter. The at least one transmitter assembly comprises at least one induction transmitter coil wound about at least one core. The at least one transmitter coil is adapted to project an induction signal outward from the outer wall when the at least one transmitter coil is carrying an electrical current. The transmitter assembly is adapted to create electromagnetic fields that originate the induction signal from outside the outer wall and substantially prevent the signal from entering the outer wall. | 10-30-2008 |
| 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 |
| 20080315883 | Method of Calibrating an Azimuthal Inductive Cross-Coil or Tilted Coil Instrument - A phase error in measurements made by a resistivity logging tool is estimated by positioning the tool above a conducting surface. Deviation of the measured phase difference between the transmitter and the receiver from 90° gives the phase error in the electronics. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. | 12-25-2008 |
| 20090160445 | Resistivity Reference Receiver - A downhole induction resistivity assembly that comprises a downhole tool string component. The tool string component comprises an induction transmitter. The transmitter is adapted to induce an induction field in the surrounding formation. A first induction receiver is spaced apart from the transmitter and is adapted to measure the induction field. A magnetic field generating mechanism is disposed adjacent on either or both sides of the transmitter and adapted to guide the transmitter's signal into the formation. A second induction receiver is disposed in close proximity to the magnetic field generating mechanism and is adapted to measure the magnetic field generated by the mechanism. | 06-25-2009 |
| 20090160446 | Resistivity Receiver Spacing - A downhole induction resistivity assembly that comprises a downhole tool string component. The tool string component comprises an induction transmitter. The transmitter is adapted to induce an induction field in the surrounding formation. A first induction receiver is spaced apart from the transmitter and is adapted to measure the induction field. A magnetic field generating mechanism is disposed adjacent on either or both sides of the transmitter and adapted to guide the transmitter's signal into the formation. A second induction receiver is disposed in close proximity to the magnetic field generating mechanism and is adapted to measure the magnetic field generated by the mechanism. | 06-25-2009 |
| 20090160447 | Independently Excitable Resistivity Units - A downhole induction resistivity assembly that comprises a downhole tool string component. The tool string component comprises an induction transmitter. The transmitter is adapted to induce an induction field in the surrounding formation. A first induction receiver is spaced apart from the transmitter and is adapted to measure the induction field. A magnetic field generating mechanism is disposed adjacent on either or both sides of the transmitter and adapted to guide the transmitter's signal into the formation. A second induction receiver is disposed in close proximity to the magnetic field generating mechanism and is adapted to measure the magnetic field generated by the mechanism. | 06-25-2009 |
| 20090160448 | Induction Resistivity Cover - A downhole induction resistivity assembly that comprises a downhole tool string component. The tool string component comprises an induction transmitter. The transmitter is adapted to induce an induction field in the surrounding formation. A first induction receiver is spaced apart from the transmitter and is adapted to measure the induction field. A magnetic field generating mechanism is disposed adjacent on either or both sides of the transmitter and adapted to guide the transmitter's signal into the formation. A second induction receiver is disposed in close proximity to the magnetic field generating mechanism and is adapted to measure the magnetic field generated by the mechanism. | 06-25-2009 |
| 20090167309 | Method of and Apparatus for Measuring Tensor Resistivity - An induction or propagation apparatus for performing measuring the tensor resistivity of a sample of matter includes a non-conductive, generally cylindrical tubular member adapted to receive the matter therein, a triaxial transmitter, at least one triaxial receiver, and an electronic module. The electronic module is adapted to energize the triaxial transmitter, control acquisition of signals by the at least one triaxial receiver, and perform anisotropic measurements and analysis. The triaxial transmitter and the at least one triaxial receiver are disposed on the generally cylindrical tubular member in axial spaced relationship. | 07-02-2009 |
| 20090237084 | Electromagnetic and Magnetostatic Shield to Perform Measurements Ahead of the Drill Bit - A transmitter on a bottomhole assembly (BHA) is used for generating a transient electromagnetic signal in an earth formation. A pair of receivers on the BHA receive signals that are indicative of formation resistivity and distances to bed boundaries. A time dependent calibration factor or a time-independent calibration factor may be used to combine the two received signals and estimate the distance to bed boundaries that are unaffected by the drill conductive body. Further improvement can be obtained by using copper shielding. | 09-24-2009 |
| 20090278543 | Systems and Methods Having Radially Offset Antennas for Electromagnetic Resistivity Logging - Disclosed herein are electromagnetic resistivity logging systems and methods that employ magnetic dipole antennas embedded in wall-contacting surfaces. In some embodiments, the antennas are pot-core or ferrite-rod antennas. Prototypes of electromagnetic resistivity logging tools having such antennas exhibit good resistivity logging performance in both water-based and oil-based borehole fluids, indicating that this architecture may yield a logging tool that is suitable for use with borehole fluids of all types. Moreover, the tool offers good spatial resolution, enabling the creation of formation resistivity images for the borehole walls. | 11-12-2009 |
| 20090295393 | Octupole Induction Sensors for Resistivity Imaging in Non-Conductive Muds - The present disclosure provides a method and apparatus for performing resistivity measurements of a borehole wall using a transverse octupole sensor. The sensor may be a resistivity sensor. Higher resolution is obtained with an octupole sensor than with lower-order-pole sensors. For the resistivity case, the ratio of dual-frequency measurements has reduced sensitivity to standoff. | 12-03-2009 |
| 20090309601 | ELECTROMAGNETIC LOGGING APPARATUS AND METHOD - An apparatus for investigating a geological formation GF surrounding a borehole WB, comprises a logging tool TL moveable through the borehole, an electromagnetic probe | 12-17-2009 |
| 20100007348 | ANISOTROPY ORIENTATION IMAGE FROM RESISTIVITY MEASUREMENTS FOR GEOSTEERING AND FORMATION EVALUATION - A method for providing an image of a formation surrounding a wellbore, includes: obtaining an apparent conductivity curve from main components of resistivity measurements of the formation; performing fitting for cross-components of the resistivity measurements; calculating scaling factors from the cross-component data; scaling apparent conductivity data by the calculated scaling factors; and plotting the scaled conductivity data to provide the image of the anisotropic formation. A system and a computer program product are disclosed. | 01-14-2010 |
| 20100052689 | Magnetic Field Deflector in an Induction Resistivity Tool - A downhole induction resistivity assembly comprises a mandrel. Disposed around the mandrel are coils of wire disposed circumferentially around magnetic field concentrators. The coils of wire and the magnetic field concentrators are disposed on an outer diameter of the mandrel. A magnetic field deflector, of magnetic permeability greater than the mandrel, is disposed intermediate the coils and the mandrel. | 03-04-2010 |
| 20100097066 | Casing Correction in Non-magnetic Casing by the Measurement of the Impedance of a Transmitter or Receiver - Methods and related systems are described for determining the casing attenuation factor for various frequencies from measurements of the impedance of the transmitting or receiving coil of wire of. The compensation is based on two relationships. The first relationship is between one or more measured impedance parameters and the product of casing conductivity, casing thickness and electromagnetic frequency. The second relationship is between the casing correction factor and the product of casing conductivity, casing thickness and electromagnetic frequency. | 04-22-2010 |
| 20100097067 | Externally Guided and Directed Field Induction Resistivity Tool - In one aspect of the invention, an induction resistivity tool incorporated into a downhole tool string comprises an outer wall of a downhole component comprising an outer diameter and at least one induction transmitter assembly disposed along the outer diameter. The at least one transmitter assembly comprises at least one induction transmitter coil wound about at least one core. The at least one transmitter coil is adapted to project an induction signal outward from the outer wall when the at least one transmitter coil is carrying an electrical current. The transmitter assembly is adapted to create electromagnetic fields that originate the induction signal from outside the outer wall and substantially prevent the signal from entering the outer wall. | 04-22-2010 |
| 20100123461 | OSCILLATOR SENSOR FOR DETERMINING A PROPERTY OF AN EARTH FORMATION - An apparatus for evaluating an earth formation, the apparatus including: a logging tool configured to be conveyed through a borehole penetrating the earth formation; a coil inductively coupled to the earth formation, the coil being disposed at the logging instrument; and a circuit coupled to the coil wherein the circuit and the coil form an oscillator circuit, the oscillator circuit being configured to oscillate when a circuit parameter of the oscillator circuit satisfies an oscillation criterion, the circuit parameter being related to a property of the earth formation. | 05-20-2010 |
| 20100127708 | Resistivity Logging with Reduced Dip Artifacts - 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. | 05-27-2010 |
| 20100134112 | DETECTING ELECTRICAL CURRENT IN A MAGNETIC STRUCTURE - A current sensor measures an electrical current flowing in well casing or other magnetic structure. The current sensor can be installed in a tool for performing electromagnetic (EM) induction surveying in a wellbore lined with an electrically conductive casing. The tool includes an EM element to transmit or receive a magnetic field through the casing. The measured current using the current sensor can be used to relate the change of casing effect on the EM element (e.g., an induction receiver) placed inside the well casing for performing the EM induction survey. | 06-03-2010 |
| 20100156424 | Robust Inversion Systems and Methods for Azimuthally Sensitive Resistivity Logging Tools - Methods and systems for determining the horizontal resistivity, vertical resistivity, and relative dip angle of anisotropic earth formations. Some of the disclosed methods and systems measure sinusoidal variation of azimuthally sensitive resistivity logging tool measurements, determine parameters representative of the sinusoidal variation, and perform inversion based on the sinusoidal parameters. When cast in this manner, the inversion process may yield more accurate and consistent resistivity and dip angle estimates. The sinusoidal parameters preferably take the form of average and peak-to-peak measurements, but may also take other forms. Moreover, use of such sinusoidal parameters enables a condensed representation of the resistivity logging tool measurements, enabling significantly more efficient communication and storage of these measurements. The condensed representations continue to enable directional boundary detection and geosteering. | 06-24-2010 |
| 20100176812 | LOOK-AHEAD BOUNDARY DETECTION AND DISTANCE MEASUREMENT - Systems and methods for look-ahead boundary detection and distance estimation are disclosed. In some embodiments, a drilling method includes extending a borehole with a drill string that includes a resistivity logging tool. The logging tool makes upward-looking and downward-looking resistivity measurements based on radial current flow. The upward looking and downward looking resistivity measurements are processed to estimate the distance to approaching bed boundaries, and drilling can be halted when the estimated distance reaches a desired value. Such information can be used to anchor casing at advantageous points and can further be used to avoid penetrating water-containing formations below a hydrocarbon reservoir. | 07-15-2010 |
| 20100176813 | ANTENNA OF AN ELECTROMAGNETIC PROBE FOR INVESTIGATING GEOLOGICAL FORMATIONS - An antenna ( | 07-15-2010 |
| 20100213943 | METHOD FOR ACCENTUATING SIGNAL FROM AHEAD OF THE BIT - A method for estimating a property of a portion of an earth formation ahead of a borehole penetrating the formation, the method includes: conveying a logging tool through the borehole; receiving one or more first signals from a previous depth of the logging tool; constructing a model of the earth formation using the one or more first signals; predicting one or more second signals from the portion of the earth formation ahead of the borehole using the model; receiving one or more third signals from the portion of the earth formation ahead of the borehole; calculating a difference between the one or more third signals and the one or more second signals; and estimating the property from the difference. | 08-26-2010 |
| 20100225322 | SYSTEM AND METHOD FOR ELEVATED SOURCE TO BOREHOLE ELECTROMAGNETIC SURVEY - Methods and systems are provided to determine a property of an earth formation, comprising a mobile transmitter disposed at a predetermined elevated height above a surface of the earth formation, and one or more receivers moveably disposed in a wellbore penetrating the earth formation. Electromagnetic energy is transmitted from the mobile transmitter into the formation from a plurality of locations; and at the one or more receivers a signal is measured. Using the signal received by the one or more receivers, a property of the formation, such as resistivity, can be determined and mapped. | 09-09-2010 |
| 20100231221 | Induction Coil Impedance Modeling using Equivalent Circuit Parameters - Methods and related systems are described for making an electromagnetic induction survey of a formation surrounding a cased section of a borehole. An electromagnetic transmitter and/or receiver is deployed into the cased section of the borehole. Electromagnetic survey measurements and impedance measurements relating to impedance of the transmitter and/or receiver are made while deployed in the section of the borehole. Compensation is made for the attenuation amplitude and/or phase in the electromagnetic survey measurements due to the conductive casing. The compensation is based on the impedance measurements and equivalent circuit parameters. The impedance measurements are correlated with numerical modeling results of a purely inductive electromagnetic transducer, and calculated equivalent circuit parameters are combined with the numerical modeling results. | 09-16-2010 |
| 20100259266 | METHOD FOR DETERMINING FLUID TYPE IN RESERVOIR - Methods are disclosed herein that relate to determining a formation type within a wellbore. The wellbore may be formed (e.g., drilled) such that the wellbore intersects fractures within a formation. An induction tool may then be disposed downhole into the wellbore for taking measurements of the formation surrounding the wellbore. These measurements may include a resistivity of the formation based upon horizontal resistivity measurement, a vertical resistivity measurement, and/or an anisotropy measurement. Using any one or all of these measurements then, one may determine a formation type of the formation measured with the induction tool. | 10-14-2010 |
| 20100259267 | ELECTROMAGNETIC LOGGING BETWEEN BOREHOLE AND SURFACE - The present disclosure relates to determining a property, such as resistivity, of an earth formation. A transmitter is disposed in a wellbore penetrating the formation, and a plurality of receivers are distributed on or near the earth's surface. The transmitter sends electromagnetic energy into the formation and the resulting signal, after passing through the formation, is detected by the array of receivers. The received signal is used to determine the property of the formation. This is often achieved using an inversion or numerical model of the formation being measured. The inversion takes into account changes in the background formation model due to transmitting from various locations. The measurements made on the formation can be performed while drilling the wellbore or subsequent to the drilling. | 10-14-2010 |
| 20100259268 | ELECTROMAGNETIC LOGGING BETWEEN A CASED BOREHOLE AND SURFACE - The present disclosure relates to systems and methods for conducting an electromagnetic borehole-to-surface survey of a formation surrounding a borehole. Such methods include deploying a dipole transmitter into the borehole to a depth of investigation, deploying an array of electromagnetic receivers outside of the wellbore, and measuring a response of the formation at the array of electromagnetic receivers deployed outside of the wellbore, for example at the surface. From the response of the formation a property of the formation can be determined based on the response of the formation measured at the array of electromagnetic receivers. For the scenario of a cased well, a local reference receiver may be added at a location proximate the borehole to measure the effective magnetic moment of the transmitter inside the casing, and normalize the formation response in order for a more accurate determination of a formation characteristic, such as resistivity. These receivers can also be used for other types of surveys. | 10-14-2010 |
| 20100295547 | Downhole Resistivity Receiver with Canceling Element - A downhole tool assembly comprising at least one downhole tool string component. The downhole tool string component comprises at least one transmitter. The transmitter is attached to a primary signal generator and transmits a primary signal into the surrounding earth formation. The primary signal creates an induced or reflected signal within the formation which may reveal information regarding the formation. The downhole tool string component also comprises at least one receiver. The receiver is adapted to measure the signal induced or reflected in the formation. The downhole tool sting component also comprises at least one active coil or piezoelectric transducer proximate the receiver. The active coil or piezoelectric transducer is adapted to substantially cancel the primary signal generated by the transmitter and allow the receiver to focus on the induced or reflected signal. | 11-25-2010 |
| 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 |
| 20110006775 | Apparatus and Method for Reducing Effects of Eccentricity in Induction Tools - In aspects, an apparatus for use in a wellbore for determining a property of an earth formation is provided. The apparatus, in one embodiment, may include a tool body including a transmitter configured to induce electromagnetic waves in an earth formation, a receiver configured to provide signals responsive to the induced electromagnetic waves, a conductive member between the transmitter and the receiver extending radially from the tool body and configured to reduce propagation of eddy currents between the transmitter and the receiver when the tool body is in a wellbore and a processor configured to process the signals provided by the receiver to determine the property of the earth formation. | 01-13-2011 |
| 20110012602 | Cancellation of Vibration Noise in Deep Transient Resistivity Measurements While Drilling - A transient electromagnetic (TEM) signal is recorded in an earth formation during vibration of a logging tool. Concurrently, accelerometer measurements are made. The accelerometer measurements are used to correct the TEM signal for the vibration using the accelerometer measurement and a transfer function relating the TEM signal and the accelerometer. The transfer function may be determined using measurements in a water tank or by using the tail end of the TEM measurements. | 01-20-2011 |
| 20110050233 | VIBRATING HELICAL SPRING SENSORS AND METHODS TO OPERATE THE SAME - Example vibrating helical spring sensors and methods to operate the same are disclosed. A disclosed example apparatus includes a housing, a helical spring held in tension, a flowline to expose the helical spring to a fluid, a magnet to expose the helical spring to a magnetic field, and a wire to electrically conduct an actuating current through the helical spring to displace the helical spring. | 03-03-2011 |
| 20110068797 | LOGGING TOOL WITH INDEPENDENTLY ENERGIZABLE TRANSMITTERS - A downhole induction resistivity assembly that comprises a downhole tool string component. The tool string component comprises an induction transmitter. The transmitter is adapted to induce an induction field in the surrounding formation. A first induction receiver is spaced apart from the transmitter and is adapted to measure the induction field. A magnetic field generating mechanism is disposed adjacent on either or both sides of the transmitter and adapted to guide the transmitter's signal into the formation. A second induction receiver is disposed in close proximity to the magnetic field generating mechanism and is adapted to measure the magnetic field generated by the mechanism. | 03-24-2011 |
| 20110074427 | Directional Resistivity Antenna Shield - A logging while drilling tool includes a directional resistivity antenna and an antenna shield having. The shield has at least one slot having at least one electrically open end formed therein. The antenna shield may include a base portion and a plurality of spaced apart fingers extending away from the base portion such that the finger ends are electrically isolated from the tool body and from one another. The antenna shield may alternatively include a plurality of spaced apart plates that are electrically isolated from the tool body and from one another. These antenna shields have been found to provide suitable physical protection for sensitive antenna components while at the same time being substantially transparent to both z-mode and x-mode electromagnetic waves. | 03-31-2011 |
| 20110074428 | Apparatus and Method for Downhole Electromagnetic Measurement While Drilling - A directional resistivity tool includes a pair of transmitters deployed between at least one pair of receivers. Each of the transmitters and receivers preferably includes collocated z-mode and x-mode antennae. Exemplary embodiments may further include additional receivers, for example, additional pairs of receivers deployed axially about the transmitters or one or more deep reading receivers deployed on one axial end of the transmitters. Tools in accordance with the invention enable directional resistivity measurements to be acquired at multiple depths of investigation using fewer transmitter firings than conventional tools. | 03-31-2011 |
| 20110140701 | DETERMINING PROPERTIES OF EARTH FORMATIONS USING THE ELECTROMAGNETIC COUPLING TENSOR - A system and method to determine earth formation properties by positioning a logging tool within a wellbore in the earth formation, the logging tool having a tool rotation axis and a first, a second, and a third tilted transmitter coil, and a tilted receiver coil; rotating the logging tool about the tool rotation axis; energizing each transmitter coil; measuring a coupling signal between each transmitter coil and the receiver coil for a plurality of angles of rotation; determining a coupling tensor; and determining the earth formation properties using the coupling tensor. | 06-16-2011 |
| 20110199088 | Electromagnetic Wave Resistivity Tool Having A Tilted Antenna For Determining The Horizontal And Vertical Resistivities And Relative Dip Angle In Anisotropic Earth Formations - This invention is directed to a downhole method and apparatus for simultaneously determining the horizontal resistivity, vertical resistivity, and relative dip angle for anisotropic earth formations. The present invention accomplishes this objective by using an antenna configuration in which a transmitter antenna and a receiver antenna are oriented in non-parallel planes such that the vertical resistivity and the relative dip angle are decoupled. Preferably, either the transmitter or the receiver is mounted in a conventional orientation in a first plane that is normal to the tool axis, and the other antenna is mounted in a second plane that is not parallel to the first plane. Although this invention is primarily intended for MWD or LWD applications, this invention is also applicable to wireline and possibly other applications. | 08-18-2011 |
| 20110215809 | DETECTION OF FORMATION STRUCTURES USING ELECTROMAGNETIC COUPLING MEASUREMENTS - The present disclosure relates to a method to determine a characteristic of a subsurface formation using electromagnetic coupling components. A downhole logging tool having one or more transmitters and one or more receivers, and being capable of measuring the electromagnetic coupling components is provided. The electromagnetic coupling components are measured using the downhole logging tool and used to form a 3-D Lateral Indicator and/or a 3-D Longitudinal Indicator. The 3-D Lateral Indicator and/or the 3-D Longitudinal Indicator are used to determine the characteristic of the subsurface formation. | 09-08-2011 |
| 20110221443 | High Frequency Dielectric Measurement Tool - Disclosed dielectric logging tools and methods employ three or more receive horn antennas positioned between at least two transmit antennas, which can also be horn antennas. The logging tools can operate in the range between 100 MHz and 10 GHz to provide logs of formation permittivity, formation conductivity, standoff distance, and electrical properties of material in the standoff gap. Logs of water-saturated porosity and/or oil movability can be readily derived. The presence of additional receive antennas offers a significantly extended operating range, additional depths of investigation, increased measurement accuracy, and further offers compensation for tool standoff and mudcake effects. In both wireline and logging while drilling embodiments, at least some disclosed dielectric logging tools employ a set of three axially-spaced receive antennas positioned between pairs of axially-spaced transmit antennas. At least some disclosed methods employ absolute amplitude and phase measurements in response to alternate firings of the transmit antennas. | 09-15-2011 |
| 20110254552 | METHOD AND APPARATUS FOR DETERMINING GEOLOGICAL STRUCTURAL DIP USING MULTIAXIAL INDUCTION MEASUREMENTS - A method for determining structural dip of subsurface formations includes accepting as input multiaxial induction measurements made by passing electric current through a multiaxial transmitter disposed in a wellbore drilled through subsurface rock formations. Voltages induced in a multiaxial receiver disposed at a longitudinally spaced apart location along the wellbore are detected while moving the transmitter and receiver along the wellbore. The multiaxial voltage measurements are inverted into values of formation dip magnitude and formation dip azimuth. A parameter related to shale content of the rock formations is measured, and structural dip of the rock formations is determined by selecting dip magnitude and dip azimuth values occurring when the parameter exceeds a selected threshold. | 10-20-2011 |
| 20110267066 | METHOD AND APPARATUS FOR GRADIENT ELECTROMAGNETIC INDUCTION WELL LOGGING - The method and apparatus for determining the conductivity of anisotropic formations surrounding a borehole. The method comprises measuring the gradient of the magnetic field by an electromagnet logging tool in a borehole in the subsurface formation. The instrument comprises one or several closely positioned parallel receiver coils and one or several closely positioned parallel transmitter coils with the magnetic direction of the transmitter coils parallel or different from the magnetic moment direction of the receiver coils. In an embodiment, a gradient induction instrument consists of a tri-axial transmitter array and up to 27 pairs of receiver coils, measuring some or all magnetic gradient components. | 11-03-2011 |
| 20110309834 | DETERMINATION OF CONDUCTIVE FORMATION ORIENTATION BY MAKING WELLBORE SONDE ERROR CORRECTION - A method for determining orientation of an electrically conductive formation proximate an electrically substantially non-conductive formation includes measuring multiaxial electromagnetic induction response within the substantially non-conductive formation using an instrument disposed in a wellbore drilled through the formations. A difference from zero conductivity is determined for each component measurement of the multiaxial electromagnetic induction response. The differences are used to correct the measured response of each component measurement in the electrically conductive response. The corrected component measurements are used to determine the orientation of the conductive formation. | 12-22-2011 |
| 20110309835 | METHOD FOR DETERMINING SPATIAL DISTRIBUTION OF FLUID INJECTED INTO SUBSURFACE ROCK FORMATIONS - A method for determining spatial distribution of fluid injected into a subsurface rock formation includes injecting the fluid into the rock formation. The fluid includes therein electrically conductive solid particles dispersed in an electrolyte. An electromagnetic response of the formation is measured. The measured electromagnetic response is used to determine spatial distribution of the injected fluid. | 12-22-2011 |
| 20110309836 | Method and Apparatus for Detecting Deep Conductive Pipe - Downhole tools and techniques acquire information regarding nearby conductors such as pipes, well casing, and conductive formations. At least some method embodiments provide a current flow along a drill string in a borehole. The current flow disperses into the surrounding formation and causes a secondary current flow in the nearby conductor. The magnetic field from the secondary current flow can be detected using one or more azimuthally-sensitive antennas. Direction and distance estimates may be obtainable from the azimuthally-sensitive measurements, and can be used as the basis for steering the drillstring relative to the distant conductor. Possible techniques for providing current flow in the drillstring include imposing a voltage across an insulated gap or using a toroid around the drillstring to induce the current flow. | 12-22-2011 |
| 20110316542 | SLOTTED SHIELD FOR LOGGING-WHILE-DRILLING TOOL - An LWD tool with a tubular having a longitudinal axis and a set of co-located antennas carried in a recess on the tubular is disclosed. The tool carries a shield having an open slot configuration and circumferentially surrounds the set of co-located antennas, a first end of the shield being mechanically and electrically connected to the tubular. The tool also includes an insulating ring carried on the tubular, at least a portion of the insulating ring being disposed between the tubular and a second end of the shield. | 12-29-2011 |
| 20120001637 | CORRECTING FOR MAGNETIC INTERFERENCE IN AZIMUTHAL TOOL MEASUREMENTS - Methods and systems that compensate for magnetic interference in azimuthal tool measurements. At least some method embodiments include a downhole logging method that includes taking measurements as a function of orientation from inside a borehole. The measurements are associated with different azimuthal bins, and an azimuthal direction is determined for each azimuthal bin. Because the tool rotates at a constant rate, the relative number of measurements associated which the different bins can be used to measure the effective sizes of the different bins and to redetermine the effective angles of the bins in the presence of magnetic interference. The tool measurements may include, but are not limited to, formation resistivity, magnetic field, and formation density. | 01-05-2012 |
| 20120025834 | DETERMINING ANISOTROPIC RESISTIVITY - The present disclosure relates to a method to determine the vertical resistivity of a subsurface formation. A downhole logging tool having a plurality of spaced antennas, at least one of which is a transverse antenna, at least two of which are tilted antennas, and at least two of which are axial antennas is provided. Measurements involving the transverse and/or the tilted antennas of the downhole logging tool are obtained. Voltage ratios are formed using the measurements, and conditioning factors are formed by raising the determined voltage ratios not involving the transverse antenna to some arbitrary power. The sum of the exponents of the conditioning factors preferably equals one. A voltage ratio involving the transverse antenna is multiplied by the conditioning factors, and the vertical resistivity of the subsurface formation is determined using the resulting ratio. | 02-02-2012 |
| 20120081122 | COMBINATIONS OF AXIAL AND SADDLE COILS TO CREATE THE EQUIVALENT OF TILTED COILS FOR DIRECTIONAL RESISTIVITY MEASUREMENTS - An electromagnetic well logging instrument includes an instrument housing, at least one transmitter coil disposed on the housing and at least one receiver coil disposed on the housing. At least one of the transmitter and receiver coils is formed from a combination solenoidal (axial) and saddle coils. The net dipole moment direction of the combined coil is determined by selecting the relative turn-areas of the saddle and solenoidal coil. The combined coil can be formed from a single wire wound to have both a longitudinal magnetic dipole moment and a transverse magnetic dipole moment with respect to a longitudinal axis of the housing. | 04-05-2012 |
| 20120119744 | SYSTEM AND METHOD FOR IMAGING PROPERTIES OF SUBTERRANEAN FORMATIONS - A system and method for imaging properties of subterranean formations in a wellbore is provided. The system comprises a formation sensor for collecting currents injected into the subterranean formations, the formation sensor positionable on a downhole tool deployable into the wellbore. The system comprises a controller for controlling the formation sensor and a formation imaging unit. The formation imaging unit comprises a current management unit for collecting data from the currents injected into the subterranean formations, the currents having at least two different frequencies. The formation imaging unit comprises a drilling mud data unit for determining at least one drilling mud parameter, a formation data unit for determining at least one formation parameter from the collected data, and an inversion unit for determining at least one formation property by inverting the at least one formation parameter. | 05-17-2012 |
| 20120169344 | USE OF ELECTRODES AND MULTI-FREQUENCY FOCUSING TO CORRECT ECCENTRICITY AND MISALIGNMENT EFFECTS ON TRANSVERSAL INDUCTION MEASUREMENTS - A multicomponent induction logging tool uses a nonconducting mandrel. A central conducting member including wires that electrically connect at least one of the antennas to another of the antennas. Electrodes disposed about the transmitter antenna form a conductive path through a borehole fluid to the central conducting member. | 07-05-2012 |
| 20120293179 | Apparatus and Method for Multi-Component Wellbore Electric Field Measurements Using Capacitive Sensors - A method and apparatus is provided for collecting reservoir data. The method includes providing one or more electromagnetic sources for generating an electromagnetic field in a reservoir and providing one or more electromagnetic sensors equipped with capacitive electrodes. The electromagnetic source is located separately from the electromagnetic sensor. The electromagnetic sensor may either be located within a well or at the surface, is capable of measuring the electromagnetic field in three dimensions, and may be isolated from the well fluids. The data collected by the electromagnetic sensors can be used to create a model of the oil reservoir, including the water saturation. | 11-22-2012 |
| 20130141103 | Induction Coil Impedance Modeling Using Equivalent Circuit Parameters - Methods and related systems are described for making an electromagnetic induction survey of a formation surrounding a cased section of a borehole. An electromagnetic transmitter and/or receiver is deployed into the cased section of the borehole. Electromagnetic survey measurements and impedance measurements relating to impedance of the transmitter and/or receiver are made while deployed in the section of the borehole. Compensation is made for the attenuation amplitude and/or phase in the electromagnetic survey measurements due to the conductive casing. The compensation is based on the impedance measurements and equivalent circuit parameters. The impedance measurements are correlated with numerical modeling results of a purely inductive electromagnetic transducer, and calculated equivalent circuit parameters are combined with the numerical modeling results. | 06-06-2013 |
| 20130141104 | Shielded Antenna For A Downhole Logging Tool - This disclosure relates to a downhole logging tool for acquiring data in an earth formation. In one embodiment, the downhole logging tool has a tool body with a longitudinal axis, a set of antennas located on the tool body and including coil windings forming a closed-loop pattern, and a shield disposed over the antennas and having an arrangement of slots with each slot being substantially perpendicular to a proximate portion of at least one of the underlying coil windings, wherein the path length around each slot is more than twice the length of the distance between the slot and a directly adjacent slot along an arc of the coil windings. The downhole logging tool may be a wireline or while-drilling tool, and it may be an induction or propagation tool. | 06-06-2013 |
| 20130234717 | Apparatus And Method For Microresistivity Imaging In Nonconductive Drilling Fluid - A microresistivity logging tool includes a transmitter coil and at least one receiver coil deployed on a tool body. The transmitter coil and receiver coil define axes that are preferably substantially perpendicular to the tool axis. | 09-12-2013 |
| 20130249561 | MULTI-AXIAL ANTENNA AND METHOD FOR USE IN DOWNHOLE TOOLS - Embodiments of a multi-axial antenna system and system for measuring subsurface formations are generally described herein. Other embodiments may be described and claimed. In some embodiments, the multi-axial antenna system comprising at least two co-located coils wound around a torroidal-shaped bobbin. Each coil generates a magnetic field in a mutually orthogonal direction. Signals provided to the coils may be adjusted to simulate a tilted-coil antenna system. | 09-26-2013 |
| 20130285665 | Signal Processing Methods for Steering to an Underground Target - A method of processing data from an electromagnetic resistivity logging tool which includes a transmitter coil and a receiver coil is disclosed. The electromagnetic resistivity logging tool is placed at a desired location. The transmitter coil and the receiver coil are positioned at a first azimuthal angle. A signal is transmitted from the receiver coil. The receiver coil then receives a signal. The signal at the receiver coil, a tilt angle of the transmitter coil, a tilt angle of the receiver coil and the first azimuthal angle are then used to calculate a first complex voltage representing at least one component of the received signal. | 10-31-2013 |
| 20130320985 | APPARATUS AND METHOD FOR DIRECTIONAL RESISTIVITY MEASUREMENT WHILE DRILLING USING AN ANTENNA WITH A JOINT-COIL STRUCTURE - An apparatus for making directional resistivity measurements of a subterranean formation includes a resistivity tool with a longitudinal axis and an outer surface, a first antenna deployed below the outer surface and having an axial mode coil for processing an axial electromagnetic wave and a transverse mode coil for processing a transverse electromagnetic wave to form a joint-coil structure, a second antenna deployed below the outer surface and spaced at an axial distance from the first antenna, at least two sets of slots with different orientations formed on the outer surface. A corresponding method for making directional resistivity measurements includes rotating a resistivity tool in a borehole, utilizing a transmitter-receiver antenna group formed in the resistivity tool to process a superimposition of the axial and transverse electromagnetic waves, and computing a resistivity-related measurement from the superimposition of the axial and transverse electromagnetic waves received on the receiver antenna. | 12-05-2013 |
| 20140015530 | ELECTRONICS FOR A THIN BED ARRAY INDUCTION LOGGING SYSTEM - A logging tool electronics system is disclosed (FIG. | 01-16-2014 |
| 20140167767 | MODULAR RESISTIVITY LOGGING TOOL SYSTEMS AND METHODS - Resistivity logging tool module systems and methods enable efficient logging string assemblies and logging operations. In some of the disclosed embodiments, a resistivity logging tool module includes a mandrel with a connector section at each end and a ring support section between the connector sections. The resistivity logging tool module also includes a composite layer disposed around the ring support section. A set of ring electrodes is positioned along the ring support section around the composite layer, wherein the composite layer electrically isolates the ring electrodes from the ring support section. One of the modules of the multi-module resistivity logging tool includes an adaptor in an isolation joint configuration with one of its connector sections. A related assembly method includes obtaining a mandrel with a connector section at each end and a ring support section between the connector sections. The method also includes disposing a composite layer around the ring support section. The method also includes moving a set of ring electrodes to a position along the ring support section, wherein the composite layer electrically isolates the ring electrodes from the ring support section. One of the modules of the multi-module resistivity logging tool includes an adaptor in an isolation joint configuration with one of its connector sections. | 06-19-2014 |
| 20140184228 | METHOD FOR TREATING AND MEASURING SUBTERRANEAN FORMATIONS - A method of treating a subterranean formation penetrated by a wellbore comprising injecting electrically conductive or electromagnetic fibers into the subterranean formation during hydraulic fracturing is provided. Suitable metallic materials, organic polymers, and organic polymers coated with or containing conductive or electromagnetic materials are described. The treatment is followed by measurement of resistivity and/or electromagnetic properties, optionally by a crosswell technique. | 07-03-2014 |
| 20140191761 | Fiberoptic Systems and Methods for Subsurface EM Field Monitoring - A disclosed subsurface electromagnetic field monitoring system employs at least one fiberoptic cable to optically communicate measurements from an array of electromagnetic field sensors in a borehole. A data processing system that receives the measurements and responsively models the subsurface electromagnetic field, which in at least some cases is generated by a controlled source such as a downhole electric or magnetic dipole source or a casing that serves as an electrode for injecting a distributed current into the formation. At least some disclosed method embodiments include: receiving measurements from an array of electromagnetic field sensors via a fiberoptic cable in a borehole; modeling a subsurface electromagnetic field based on estimated formation parameters to predict said measurements; adjusting the estimated formation parameters to improve a match between predicted measurements and received measurements; and displaying the estimated formation parameters after matching the predicted measurements to the received measurements. | 07-10-2014 |
| 20140218037 | Intelligent Spectral Induced Polarization Measurement Module - A system for spectral induced polarization measurement of a formation is provided. The system provides an intelligent module to be utilized in performing spectral induced polarization (SIP) measurements for geophysical studies or otherwise. The system includes a instrument that includes a housing configured to be inserted into a surface opening. The housing houses a signal generator that generates an excitation signal. A drive electrode directs the excitation signal into the material adjacent the housing. A plurality of electrodes sense the voltage and/or current in the material adjacent the housing and a processor processes the sensed voltage and/or current to measure a property of the material. The system also provides a configuration in which a plurality of instruments configured for spectral induced polarization measurements are interconnected to provide communication, synchronization, a common reference signal or power. | 08-07-2014 |
| 20140292341 | Method and Tool for Directional Electromagnetic Well Logging - A directional antenna, system and method are provided. The methods include acquiring a plurality of data pairs, each data pair comprising an induced signal at a receiver and a corresponding toolface angle using a tool including at least one antenna assembly, as described herein. It further discloses a method to generate a measurement containing information about the directionality of the formation by calculating areas of an induced signal function approximated by the plurality of data pairs. | 10-02-2014 |
| 20140368201 | Systems and Methods for Downhole Electromagnetic Field Measurement - Sensors, systems and methods for downhole electromagnetic field measurement, including a downhole micro-opto-electro-mechanical system (MOEMS) electromagnetic field sensor that includes a first surface that is at least partially reflective, a second surface that is at least partially reflective and suspended by one or more flexible members to define an optical cavity having a variable distance between the first and second surfaces, a first conductive layer attached to the first surface, and a second conductive layer attached to the second surface. The first and second conductive layers have an electrical potential proportional to an electromagnetic field within a formation surrounding the sensor. The electrical potential produces an electric field that displaces the second surface to alter the variable distance and cause a spectrum variation in light exiting the sensor. | 12-18-2014 |
| 20140368202 | Systems and Methods for Downhole Electric Field Measurement - Sensors, systems and methods for downhole electromagnetic field detection, including a downhole micro-opto-electro-mechanical system (MOEMS) electromagnetic field sensor that includes a first surface that is at least partially reflective, a second surface that is at least partially reflective and suspended by one or more flexible members to define an optical cavity having a variable distance between the first and second surfaces, and a first conductive layer attached to the second surface and having a first electric charge. An electric field passing through the optical cavity interacts with the first electric charge and displaces the second surface to alter the variable distance and cause a spectrum variation in light exiting the sensor. | 12-18-2014 |
| 20140368203 | Systems and Methods for Downhole Magnetic Field Measurement - Sensors, systems and methods for downhole electromagnetic field detection, including a downhole micro-opto-electro-mechanical system (MOEMS) electromagnetic field sensor that includes a first surface that is at least partially reflective, a second surface that is at least partially reflective and suspended by one or more flexible members to define an optical cavity having a variable distance between the first and second surfaces, and a magnetically polarized layer attached to the second surface. A magnetic field passing through the optical cavity interacts with the magnetically polarized layer and a gradient in the magnetic field produces a displacement of the second surface that alters the variable distance and causes a spectrum variation in light exiting the sensor. | 12-18-2014 |
| 20150008927 | Methods and Systems for Obtaining an Electrical Impedivity and/or Resistivity Image of a Subterranean Formation - Methods and systems for obtaining an electrical impedivity and/or resistivity image of a subterranean formation are provided. The electrical impedivity and/or resistivity image can be obtained by determining first formation impedivity data and second formation impedivity data. The first formation impedivity data can be based on a component of the measured impedance data orthogonal a downhole fluid impedance. The second formation impedivity data can be based on an amplitude of the measured impedance data. A combined formation impedivity data can be obtained by combining a portion of the first formation impedivity data based on a first formation impedivity determination process with a portion of the second formation impedivity data based on a second formation impedivity determination process. The electrical impedivity and/or resistivity image of the subterranean formation can then be obtained by using the combined formation impedivity data. | 01-08-2015 |
| 20150008928 | Electronics for a Thin Bed Array Induction Logging System - A logging tool electronics system is disclosed with noise minimization features and pulse compression signal processing techniques to improve the signal-to-noise ratio of array induction logging tools. The borehole is radiated with a magnetic field produced by a configurable multi-frequency and/or multi-amplitude sine wave signal stimulus section driving a fully differential single transmitter coil. Received signals from multiple mutually balanced fully differential receiver arrays are processed by receiver signal chains using adaptive algorithms under firmware control. The received signals are used to determine the conductivity and resistivity of the formation surrounding the borehole. | 01-08-2015 |
| 20150015265 | Look Ahead Logging System - A technique utilizes the acquisition of data from desired subterranean regions via a logging system. The logging system is constructed for use in a wellbore and comprises a transmitter module having a transmitter antenna. Additionally, the logging system utilizes a receiver module spaced from the transmitter module and having a receiver antenna. The transmitter antenna and the receiver antenna are oriented to enable sensitivity in desired directions, such as ahead of the logging system. | 01-15-2015 |
| 20150035536 | DETECTING BOUNDARY LOCATIONS OF MULTIPLE SUBSURFACE LAYERS - Systems, methods, and software for detecting boundary locations of multiple subsurface layers are described. In some aspects, the boundaries of multiple subsurface layers in a subterranean region are identified based on measurements associated with multiple different transmitter-receiver spacings. The measurements are generated based on operating multiple transmitters and multiple receivers of a resistivity logging tool at a tool depth in a wellbore in the subterranean region. A first pair of the subsurface boundary locations are determined based on a first measurement associated with a first transmitter-receiver spacing. A second, different pair of the subsurface boundary locations are determined based on a second measurement associated with a second, longer transmitter-receiver spacing. The first pair of subsurface boundary locations reside between the second pair of subsurface boundary locations in the subterranean region. | 02-05-2015 |
| 20150061682 | Shielded Antenna For A Downhole Logging Tool - A downhole logging tool includes a tool body having a co-located set of antennas located on the tool body and first and second antennas formed from respective first and second pairs of coil windings having a closed-loop pattern. Both the first and second pair of coil windings are arranged on diametrically opposed antenna sections. A cylindrical shield is disposed over the co-located set of antennas and has a first set of vertical slots arranged interposed between each of the underlying antenna sections, a second set of vertical slots arranged over each of the underlying antenna sections, with each of the second set of vertical slots being perpendicular to a portion of the coil winding in the underlying antenna section, and a set of non-vertical slots arranged over each the underlying antenna sections. Each of non-vertical slots is perpendicular to a portion of the coil winding in the underlying antenna section. | 03-05-2015 |
| 20150115965 | Induction Logging Sensor - Apparatuses and methods are provided herein that may improve sensitivity to transient signals. For example, an electromagnetic sensor for downhole measurements that includes a plurality of sectors (e.g., four quadrants) is provided herein. Each quadrant may include a magnetic core formed of a material with a high initial magnetic permeability to improve sensitivity to transient signals. A sensor for continuous wave induction tools is also provided, and may include a magnetic core formed of a material with a high initial magnetic permeability. Forming each sector magnetic core of a material with a high mechanical reliability may allow the magnetic core of the corresponding sensor to be pliable and flexible and not brittle and prone to breaking. Furthermore, the corresponding sensor may have enhanced sensitivity, greater stability of sensitivity relative to temperature changes, and high mechanical reliability. | 04-30-2015 |
| 20150293255 | RESISTIVITY OF CHEMICALLY STIMULATED RESERVOIRS - A chemical stimulation system and a resistivity tool are disposed in a wellbore. Chemical stimulation operations are performed in the wellbore using the chemical stimulation system. Resistivity measurements are made with the resistivity tool before, during, and/or after the chemical stimulation operations. The resistivity measurements may be used to determine the porosity of a formation penetrated by the wellbore. A wormhole distribution and/or penetration in the formation is determined based on the resistivity measurements. Decisions regarding stimulation operations are made based on the determined wormhole distribution and/or penetration. The resistivity tool may be modular and have various arrays allowing various depths of investigation. The depths of penetration of the wormholes into the formation may be determined using the measurements from the multiple depths of investigation. The volume of the formation that is dissolved by the chemical stimulation operations may also be estimated. | 10-15-2015 |
| 20150301218 | FORMATION IMAGING WITH MULTI-POLE ANTENNAS - Various embodiments include systems and methods that operate to provide reservoir imaging. The systems and methods can include a number of transmitter antennas and a number of receiving antennas arranged to operate as one or more multi-pole antennas, controlled to generate high resolution cross-well formation images. Additional apparatus, systems, and methods are disclosed. | 10-22-2015 |
| 20150331139 | SYSTEMS AND METHODS FOR PERFORMING RANGING MEASUREMENTS USING THIRD WELL REFERENCING - Systems and methods for obtaining ranging measurements are described herein. An example method includes injecting a current | 11-19-2015 |
| 20150355368 | METHODS AND SYSTEMS FOR DETERMINING FORMATION PARAMETERS USING A ROTATING TOOL EQUIPPED WITH TILTED ANTENNA LOOPS - Methods and systems for characterizing a formation are disclosed. A tool is placed in the formation. The tool comprises a perpendicular antenna set and a parallel antenna set. The perpendicular antenna set comprises at least one transmitter antenna oriented perpendicular to at least one receiver antenna and the parallel antenna set comprises at least one transmitter antenna oriented parallel to at least one receiver antenna. Data is obtained from the tool and used to determine a compensated geosignal for each of the perpendicular antenna set and the parallel antenna set. The determined compensated geosignal is used to characterize the formation. | 12-10-2015 |
| 20150369951 | APPARATUS AND METHODS TO FIND A POSITION IN AN UNDERGROUND FORMATION - Various embodiments include apparatus and methods related to finding a position in an underground formation. Apparatus and methods can include receiving signals from a receiver in an underground formation in response to signals generated from transmitting sources, each of the transmitting sources located at a known position; and processing the received signals, based on the signals generated from the transmitting sources, to determine the position of the receiver. A number of techniques can be applied to processing the received signal. Additional apparatus, systems, and methods are disclosed. | 12-24-2015 |
| 20150378046 | DOWNHOLE TOOL WITH RADIAL ARRAY OF CONFORMABLE SENSORS FOR DOWNHOLE DETECTION AND IMAGING - According to aspects of the present disclosure, an example downhole tool may include tool body, a first pad radially extendable from the tool body, and a radial array of conformable sensors coupled to the first pad. At least one conformable sensor of the radial array of conformable sensors may include a first flexible material. A transmitter may be coupled to one of the tool body and the first flexible material, and a receiver may be coupled to one of the tool body and the first flexible material. At least one of the transmitter and the receiver may be coupled to the first flexible material. | 12-31-2015 |
| 20160003962 | Electromagnetic Time-Lapse Remote Sensing of Reservoir Conditions - A method for sensing a condition of a hydrocarbon reservoir from a subterranean well having a lined section with a liner and an unlined section includes attaching an electric current sensor to the liner proximate to a lower end of the lined section and a plurality of electromagnetic sources located along the unlined section. The electromagnetic sources are activated independently and the resulting current induced in the liner by each electromagnetic source is measured with the electric current sensor. These measurements can be inverted to determine the spatial distribution of the electric conductivity within the reservoir and its changes in time due to fluid substitution during production. Alternatively, a fast and robust method for interpretation of the data is presented for early detection and location of a possible water front approaching the production well. | 01-07-2016 |
| 20160003971 | CALIBRATION RESISTIVITY TOOLS IN ENVIRONMENTS WITH RADIO-FREQUENCY NOISE - Systems and methods for calibrating resistivity tools in environments with radio-frequency (RF) noise are described herein. The method may include receiving a first measurement from a resistivity tool. The measurement may be taken with the resistivity tool elevated to reduce ground effects on the measurements. The first measurement may be altered by excluding at least some RF noise from the first measurement. The RF noise may be a by product of the resistivity tool being elevated. Additionally, the resistivity tool may be calibrated using the altered first measurement. | 01-07-2016 |
| 20160018553 | DIP CORRECTION USING ESTIMATED FORMATION LAYER RESISTIVITIES - In some embodiments, an apparatus and a system, as well as a method and an article, may operate to determine apparent resistivity values of the formation associated with each of several layers comprising a set of at least three layers; to determine a resistivity correction for a selected one of the layers based on at least one of the apparent resistivity value of the selected layer, the width of the selected layer, and the apparent resistivity values in layers of the set located above and below the selected layer in the set within which the apparent resistivity value was obtained; and to generate a dip corrected resistivity value associated with the selected layer, based on the resistivity correction. Methods described herein may operate without using inversion-based or filter-based methods of dip correction. Additional apparatus, systems, and methods are disclosed. | 01-21-2016 |
| 20160025887 | TARGET WELL RANGING METHOD, APPARATUS, AND SYSTEM - A ranging signal and a reference signal are generated. The reference signal has a lower frequency than the ranging signal. The reference signal is transmitted through a geological formation to be received by a ranging tool in a ranging well while the ranging signal is launched down a target well. The reference signal is reconstructed in the ranging well and a signal that is a combination of the ranging signal launched from the target well and noise are received in the ranging well. The received signal may be in the form of magnetic or electric field values or changes in these fields. The reconstructed reference signal, in combination with the received signal, is used to produce a filtered ranging signal. A relative location of the target well can then be determined in relation to the ranging well based on the filtered ranging signal. The location information can be used to direct drilling operations. | 01-28-2016 |
| 20160033669 | ANTENNA COUPLING COMPONENT MEASUREMENT TOOL HAVING A ROTATING ANTENNA CONFIGURATION - Disclosed herein are electromagnetic resistivity logging systems and methods that employ an antenna configuration having at most two transmitter or receiver antenna orientations that rotate relative to the borehole. The measurements made by this reduced-complexity antenna configuration enable the determination of at least seven components of a coupling matrix, which may be determined using a linear system of equations that express the azimuthal dependence of the measurements. For increased reliability, measurement averaging may be performed in azimuthally spaced bins. The coupling matrix components can then be used as the basis for determining logs of various formation parameters, including vertical resistivity and anisotropy. | 02-04-2016 |
| 20160054468 | Identifying Unconventional Formations - Signal measurements collected by azimuthally sensitive electromagnetic logging tool as a function of position in a borehole are obtained. The signal measurements are used to identify a type of formation model. An inversion technique appropriate to the type of formation model is applied to the set of signal measurements to determine a geophysical property. The geophysical property is used to make a decision regarding drilling a well. | 02-25-2016 |
| 20160061776 | Method and Device for Multi-Sensor Electromagnetic Defectoscopy of Well Casings - A group of inventions related to geophysical well logging, in particular to magnetic imaging defectoscopy of well casings including magnetised ones, that can be used to identify and classify defects in production and intermediate casing and tubing strings in oil and gas wells. An electromagnetic multi-sensor defectoscope for surveying casing pipes containing a source of the electromagnetic field in the form of a central exciter coil designed to transmit current pulses from a current pulse generator, a system of measuring elements placed on bow springs to be forced against the inner surface of a casing pipe, and a unit for signal recording, control and data processing connected to the system of measuring elements through communication lines. A method of multi-sensor electromagnetic defectoscopy for surveying casing pipes. | 03-03-2016 |
| 20160070018 | Measurement Compensation Using Multiple Electromagnetic Transmitters - Systems, methods, and devices for compensating for environmental conditions on electromagnetic measurements are provided. For example, a downhole logging tool may include a first transmitter coil, a second transmitter coil, and a first receiver coil. The first transmitter coil may provide a first magnetic signal in a wellbore having a conductive casing. The second transmitter coil may provide a second magnetic signal in the wellbore. The first receiver may obtain a first measurement relating to the first magnetic signal and a second measurement relating to the second magnetic signal. The first receiver coil may be near enough to the first transmitter coil and the second transmitter coil to obtain measurements predominantly in the near field eddy current regime. A ratio of the first measurement and the second measurement may cancel environmental dependencies of the first receiver coil. | 03-10-2016 |
| 20160077236 | ELECTROMAGNETIC SENSING APPARATUS FOR BOREHOLE ACOUSTICS - An example method for determining borehole acoustics using an electromagnetic sensing apparatus may include positioning a downhole tool within a borehole disposed in a formation. The downhole tool may comprise at least one acoustic source and at least one electromagnetic (EM) sensor. An acoustic wave may be emitted from the at least one acoustic source. The acoustic wave may generate an electrical signal when an EM field is present within the borehole. The electrical signal may be measured with the at least one EM sensor. At least one downhole characteristic may be determined based, at least in part, on the measured electrical signal. | 03-17-2016 |
| 20160091628 | Directional Antennas For Electromagnetic Mapping In a Borehole - A bottom hole assembly used for a field operation is disclosed herein. The bottom hole assembly can include at least one directional antenna disposed on an outer surface of a first tubing pipe of a tubing string, where the at least one directional antenna receives a first electric current from at least one power source, where the first electric current generates a first magnetic field that radiates from the at least one directional antenna into a formation. The bottom hole assembly can also include at least one receiver disposed on a second tubing pipe of the tubing string, where the at least one receiver receives the first magnetic field returning from the formation. | 03-31-2016 |
| 20160116624 | Use of Transverse Antenna Measurements for Casing and Pipe Detection - Disclosed herein is a method of determining a relation between a resistivity logging tool and casing in an earth formation. The method includes acquiring coupling voltages for different tool face angles, between different antenna components of different axes of a transmitting station transmitting into the earth formation and different antenna components of different axes of a receiving station receiving from the formation, using the resistivity logging tool. Then, spatial Fourier coefficients are extracted from the coupling voltages, using a computing device associated with the resistivity logging tool. The relation between the resistivity logging tool and the casing is then determined as a function of the spatial Fourier coefficients and at least one resistivity measurement of the earth formation, using the computing device. | 04-28-2016 |
| 20160124107 | APPARATUS AND METHODS FOR MAKING AZIMUTHAL RESISTIVITY MEASUREMENTS - A resistivity measuring tool used in a drillstring having a drill bit on a distal end for drilling a wellbore in a formation includes a tool body having a longitudinal axis, a sensor configured to measure the angular position of the tool body relative to the wellbore, at least one axial antenna including a wire winding for generating an axial magnetic moment parallel with the longitudinal axis, and at least one transverse antenna. The transverse antenna includes an antenna body disposed within a pocket extending radially inward from an outer surface of the tool body and one or more turns of wire wound around the antenna body, the wire winding generating a transverse magnetic moment orthogonal to the longitudinal axis. | 05-05-2016 |
| 20160154134 | COMPENSATED BOREHOLE AND PIPE SURVEY TOOL WITH CONFORMABLE SENSORS | 06-02-2016 |
| 20160170068 | SURFACE CALIBRATION OF A WELLBORE RESISTIVITY LOGGING TOOL | 06-16-2016 |
| 20160178780 | Antenna Transmitter Health Determination and Borehole Compensation for Electromagnetic Measurement Tool | 06-23-2016 |
| 20160178782 | MULTI-SENSOR SYSTEM FOR AIRBORNE GEOPHYSICAL PROSPECTING AND METHOD | 06-23-2016 |
| 20160187523 | FOCUSED SYMMETRIC PIPE INSPECTION TOOLS - An electromagnetic sensor for a pipe inspection tool includes a first coil antenna having a wire wrapped about a first core in a first direction, and a second coil antenna axially offset from the first coil and the wire wrapped about a second core in a second direction. A power source is coupled to the wire such that, when excited by the power source, the first coil antenna generates a first magnetic field in a first polar orientation and the second coil antenna generates a second magnetic field in a second polar orientation opposite the first polar orientation. | 06-30-2016 |
| 20160187524 | Method and apparatus for mapping the underground soil - The invention describes a method and system, for mapping non-magnetic soils in terms of their local permittivity and velocity of the traversing electromagnetic waves, by measuring the straight-line attenuation and elapsed time between transmitters and receivers located within tubes inserted into the soil. | 06-30-2016 |
| 20160195631 | SYSTEM AND METHOD FOR GROUNDWATER DETECTION AND EVALUATION | 07-07-2016 |
| 20160202382 | Modified Triaxial Antenna Array | 07-14-2016 |
| 20160202383 | APPARATUS, METHODS AND SYSTEMS FOR DOWNHOLE TESTING OF ELECTRONIC EQUIPMENT | 07-14-2016 |
| 20160252645 | STEERABLE MAGNETIC DIPOLE ANTENNA FOR MEASUREMENT WHILE DRILLING APPLICATIONS | 09-01-2016 |
| 20190145247 | INSPECTION OF PIPES WITH BUCKLING EFFECTS | 05-16-2019 |
