Patent application number | Description | Published |
20090005995 | Method and Apparatus for Characterizing and Estimating Permeability Using LWD Stoneley-Wave Data - Stoneley-wave data acquired in the LWD environment are used to characterize/estimate formation permeability. Real-time Stoneley-wave time-delay/slowness and center-frequency/attenuation data are used to indicate/characterize formation permeability even during drilling. The use of stabilizers mounted at the tool ends helps maintain the tool position from severe decentralization, reducing ambiguities in the permeability characterization/estimation. 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. | 01-01-2009 |
20090034366 | VSP Pattern Recognition in Absolute Time - A procedure to determine VSP-WD (Vertical Seismic Profiling—While Drilling) first breaks in absolute time is described. By combining a seismic surface source and firing complex seismic pattern unique in time (with a highly accurate surface—downhole time reference system), an automatic downhole procedure for first break detection on the downhole data, even under harsh conditions (low signal to noise ratio), is established. 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. 37 CFR 1.72( | 02-05-2009 |
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 |
20090173150 | Early Kick Detection in an Oil and Gas Well - A stepped reflector on the outside of a bottomhole assembly produces two reflections in response to excitation of a transducer. The velocity of the fluid in the borehole is estimated using the two reflections. Alternatively, a change in the gas content of the borehole fluid is estimated from changes in the electrical impedance of a transducer in contact with the borehole fluid. | 07-09-2009 |
20090185446 | Identification of Stress in Formations Using Angles of Fast and Slow Dipole Waves in Borehole Acoustic Logging - Cross-dipole measurements are obtained in a borehole. By estimating a direction of polarization of the fast shear mode at low and high frequencies and comparing the estimated distances, a cause of anisotropy is established. Formation stresses and directions may be estimated. | 07-23-2009 |
20090195408 | METHODS AND APPARATUS FOR HIGH-SPEED TELEMETRY WHILE DRILLING - A seismic and/or acoustic while drilling configuration includes a high speed telemetry arrangement; at least one seismic and/or acoustic energy sensor in communication with the high speed telemetry arrangement; at least one seismic and/or acoustic energy source capable of producing at least one seismic and/or acoustic energy signal receivable by the at least one seismic and/or acoustic energy sensor and methods. | 08-06-2009 |
20090205899 | Acoustic Imaging Away From the Borehole Using a Low-Frequency Quadrupole Excitation - Acoustic measurements made in a borehole using a multipole source are used for imaging a near-borehole geological formation structure and determination of its orientation. The signal to noise ratio (as defined by the ratio of the signal radiated into the formation to the axially propagating signal) depends upon the type of source (force or volume) and its position in the borehole (on the tool, in the fluid or on the borehole wall). | 08-20-2009 |
20090213690 | Composite Transducer for Downhole Ultrasonic Imaging and Caliper Measurement - A transducer assembly for downhole imaging includes a 1-3 Piezoelectric composite transducer of high Q ceramic rods in a polymer matrix. The assembly also includes a Teflon® window, a fluid-filled cavity adjacent to the window, and impedance matching material between the composite transducer and the fluid. The transducer is positioned to reduce the reverberation time. | 08-27-2009 |
20090231954 | Micro-Annulus Detection Using Lamb Waves - A method, apparatus and computer-readable medium for identifying a micro-annulus outside a casing in a cemented wellbore. The attenuation of a Lamb wave and a compressional wave is used to determine a presence of a micro-annulus between the casing and the cement. | 09-17-2009 |
20090296522 | METHOD AND SYSTEM FOR DELINEATING A SECOND WELLBORE FROM A FIRST WELLBORE - Disclosed herein is a method of delineating a second wellbore from a first wellbore. The method includes, emitting acoustic waves from a tool in the first wellbore, receiving acoustic waves at the tool reflected from the second wellbore, and determining orientation and distance of at least a portion of the second wellbore relative to the tool. | 12-03-2009 |
20100085835 | NOVEL CURVE-FITTING TECHNIQUE FOR DETERMINING DISPERSION CHARACTERISTICS OF GUIDED ELASTIC WAVES - A method for estimating a slowness of an earth formation, the method including: transmitting acoustic energy into the earth formation using an acoustic source; receiving the acoustic energy with an array of acoustic receivers, each acoustic receiver being configured to provide acoustic waveform data related to the received acoustic energy; transforming the acoustic waveform data into a frequency domain to provide frequency domain data; calculating a slowness-frequency coherence function using the frequency domain data; selecting slowness dispersion data from peaks of the slowness-frequency coherence function; fitting a curve to the slowness dispersion data; and estimating the slowness from the curve. | 04-08-2010 |
20100097887 | Active Noise Cancellation Through the Use of Magnetic Coupling - Passive suppression of casing signals is used to improve the ability to measure formation velocities. Passive suppression includes the use of a magnet slidably coupled to the casing. | 04-22-2010 |
20100142319 | Electromagnetic Linear Drive Source for Logging-While-Drilling/Wireline Acoustic Applications - An apparatus and method for providing a downhole acoustic source is disclosed. The acoustic source includes a piston configured to oscillate in an axial direction of the acoustic source and produce an acoustic signal in a medium in contact with an exterior surface of the piston, and an elastomer disposed on an interior side of the piston, an acoustic impedance of the elastomer selected to match an acoustic impedance of the piston. A permanent magnet is configured to provide a permanent magnetic field oriented in the axial direction, and a coil disposed on an interior side of the piston produces an alternating magnetic field in the region of the permanent magnetic field. The elastomer may be, for example, a silicon rubber, a silicone jelly, and a silicone oil. A plurality of acoustic sources may be arranged to produce an acoustic dipole configuration or an acoustic quadrupole configuration. | 06-10-2010 |
20100246325 | Method and Apparatus for Acoustic Impedance and P-Wave Anisotropy Measurements - Measurements of impedance are made using a piezoelectric transducer oriented at different angles to a formation bedding plane. The impedance measurements are then used to estimate the anisotropic velocity of the formation. | 09-30-2010 |
20100263449 | Casing Thickness Evaluation Method - Evaluating casing thickness by inducing SH0 and SH1 modes of a shear wave in the casing. The SH0 group velocity and SH1 mode group velocity (Vg) are measured and the measured SH0 mode group velocity is assigned as the tubular material shear velocity (Vs). A shear wave wavelength λ from the ratio of SH0 mode frequency (f | 10-21-2010 |
20100265796 | Televiewer Image Wood-Grain Reduction Techniques - Measurements made by a transducer assembly for downhole imaging are affected by reverberations between the transducer and the window on the outside of the assembly. The reverberations result in a stationary noise on the image. Hardware solutions to improve signal-to-noise ratio includes using a composite transducer, adjusting the distance between the transducer and the window. SNR can also be improved by processing techniques that include stacking, fitting a sinusoid to the reverberation, by envelope peak detection, and by applying a notch filter. | 10-21-2010 |
20100309748 | Method and Apparatus for Determining Radial Shear Velocity Variation From Dipole Acoustic Logging - A radial shear velocity profile of an earth formation is obtained by using dipole and/or cross-dipole measurements. The non-uniqueness in the inversion is addressed by using a constraint based on the fact that high-frequency dipole shear waves are mostly sensitive to the near-borehole shear velocity. | 12-09-2010 |
20110108325 | Integrating Multiple Data Sources for Drilling Applications - A drilling system makes measurements of at least one drilling parameter such as downhole weight on bit, bit torque, bit revolutions, rate of penetration and bit axial acceleration, and at least one measurement responsive to formation properties. One or more processors use the measurements of drilling parameters and formation properties to adjust drilling parameters. | 05-12-2011 |
20120037423 | Low Frequency Formation Shear Slowness From Drilling Noise Derived Quadrupole Array Data - The present disclosure is related to apparatuses and methods measuring and processing a characteristic of subsurface earth formations penetrated by a borehole. More specifically this present disclosure relates to a method and apparatus for measuring and processing an acoustic characteristic such as formation shear wave velocity of subsurface sonic waves after these waves traverse earth formations adjoining a borehole or passing through a portion of the subsurface. The apparatus may include: a bottomhole assembly, a drill bit configured to generate an acoustic signal, at least two acoustic detectors, and a processor. The acoustic signal may include a specific multipole signal that may propagate through an earth formation along the borehole. The method may include use of the apparatus, including steps for estimating a shear velocity of the acoustic signal using signals from the at least two acoustic detectors. | 02-16-2012 |
20120109528 | RADON MIGRATION OF ACOUSTIC DATA - Disclosed is a method implemented by a processor for imaging a formation penetrated by a borehole. The method includes: obtaining acoustic data in a depth-time domain using an acoustic downhole tool disposed at a depth in the borehole, the acoustic downhole tool having an acoustic source and an acoustic receiver; transforming the acoustic data in the depth-time domain into a Radon domain using a Radon transform; filtering the acoustic data in the Radon domain to increase a signal of interest in the acoustic data in the Radon domain; determining a location of a point in the formation that reflected acoustic energy emitted from the acoustic source to the acoustic receiver, the location of the point being represented in the Radon domain; and inverting the location of the point represented in the Radon domain into a radius-depth domain to image the formation. | 05-03-2012 |
20130099791 | Methodologies to Improve Reliability of Transducer Electrical Interconnections - The present disclosure relates to methods and apparatuses measuring a property of a material. The apparatus may include a transducer comprising a first electrical conductor, a second electrical conductor, and a piezoelectric component configured to receive the two conductors. The piezoelectric component may include a cavity dimensioned to improve the strength of or reduce stress on an interconnection between piezoelectric component and at least one of the conductors. The method may include using one or more transducers measuring a property of a material. In some embodiments, the material may be an earth formation. | 04-25-2013 |
20140104978 | TELEVIEWER IMAGE WOOD-GRAIN REDUCTION TECHNIQUES - Measurements made by a transducer assembly for downhole imaging are affected by reverberations between the transducer and the window on the outside of the assembly. The reverberations result in a stationary noise on the image. Hardware solutions to improve signal-to-noise ratio includes using a composite transducer, adjusting the distance between the transducer and the window. SNR can also be improved by processing techniques that include stacking, fitting a sinusoid to the reverberation, by envelope peak detection, and by applying a notch filter. | 04-17-2014 |
20150013974 | FRACTURE EVALUATION THROUGH CASED BOREHOLES - A method of estimating fractures in an earth formation includes: disposing an acoustic tool in a cased borehole in an earth formation, the acoustic tool including a multipole acoustic transmitter and an acoustic receiver; transmitting an acoustic signal into the borehole; measuring deep shear wave (DSW) signals generated from shear body waves reflected in the formation in a far-field region of the formation around the borehole; and estimating at least a location and an orientation of a fracture in the formation based on the DSW signals. | 01-15-2015 |