Signal Processing Patents (Class 367/21)
  • Patent number: 8010291
    Abstract: To process measurement data representing a subterranean structure, a derivative of the measurement data collected by at least one survey receiver is computed, with respect to frequency. A response representing the subterranean structure is then computed based on the derivative of the measurement data, where the response contains an air-wave component that has been suppressed due to computing the derivative of the measurement data relative to at least another component that is sensitive to the subterranean structure.
    Type: Grant
    Filed: November 8, 2008
    Date of Patent: August 30, 2011
    Assignee: WesternGeco L.L.C.
    Inventors: Jiuping Chen, David L. Alumbaugh, Edward Nichols, Stephen A. Horne, Kevin Eyl
  • Publication number: 20110176384
    Abstract: Apparatus, computer instructions and method for processing seismic data related to a subsurface of a body of water. The method includes inputting data indicative of recordings made by detectors provided on a curved profile in response to an acoustic wave reflected from the subsurface; applying a matched mirror migration procedure to the data, where (i) actual positions of the detectors on the curved profile and corresponding recordings, and (ii) fictitious mirror positions of the actual detectors on the curved profile and corresponding recordings with a changed sign are added in the matched mirror migration; and generating a final image of the subsurface based on the matched mirror migration procedure.
    Type: Application
    Filed: January 18, 2011
    Publication date: July 21, 2011
    Applicant: CGGVERITAS SERVICES SA
    Inventor: Robert SOUBARAS
  • Patent number: 7969818
    Abstract: Seismic data from towed marine streamers are sorted into two-dimensional common midpoint gathers of traces. The gathered traces are ordered by offset. The offset distribution of the ordered traces is regularized. The source and receiver coordinates of the regularized traces are adjusted to reflect the regularizing.
    Type: Grant
    Filed: December 19, 2007
    Date of Patent: June 28, 2011
    Assignee: PGS Geophysical AS
    Inventor: Jonathan Mark Burren
  • Publication number: 20110149683
    Abstract: A method for seismic exploration of subsurface rock formations includes actuating an impulsive seismic energy source proximate the rock formations. A non-impulsive seismic energy source is actuated. A near field waveform of each of the impulsive and non-impulsive seismic energy sources is detected. A far field waveform of the combined output of the impulsive and non-impulsive seismic energy sources is determined from the near field waveforms. An impulse response of the subsurface rock formations is determined by deconvolving the far field waveform with detected seismic signals.
    Type: Application
    Filed: December 21, 2009
    Publication date: June 23, 2011
    Inventors: Nils Lunde, Antoni Marjan Ziolkowski, Gregory Emest Parkes
  • Patent number: 7961551
    Abstract: A technique includes obtaining seismic data acquired by at least one seismic sensor. The technique includes processing the seismic data to determine a value that is indicative of a three-dimensional directional propagation attribute of a seismic event based on the seismic data.
    Type: Grant
    Filed: March 21, 2008
    Date of Patent: June 14, 2011
    Assignee: WesternGeco L.L.C.
    Inventors: Johan Robertsson, Dirk-Jan Van Manen, Susanne Rentsch
  • Patent number: 7957221
    Abstract: A method for determining upgoing pressure components of seismic signals from signals detected by combined pressure responsive sensors and motion responsive seismic sensors disposed in a plurality of laterally spaced apart streamers includes determining a threshold time at which angle of incidence error in the motion responsive signals in the cross-line direction falls below a selected threshold. Below the threshold time, the motion responsive signals are corrected for angle of incidence in the in-line and cross-line directions. Above the threshold time, the motion responsive signals are corrected for angle of incidence only in the in-line direction. Both sets of incidence corrected measured motion responsive signals, and the pressure responsive signals are used to determine upgoing or downgoing pressure components or upgoing or downgoing motion components of the measured motion responsive and pressure responsive seismic signals.
    Type: Grant
    Filed: November 14, 2008
    Date of Patent: June 7, 2011
    Assignee: PGS Geophysical AS
    Inventors: Tilman Klüver, Hocine Tabti, Anthony James Day
  • Patent number: 7957906
    Abstract: A calculated vertical velocity sensor signal is determined from a recorded pressure sensor signal. A constructed vertical velocity sensor signal is determined as a linear combination of the calculated vertical velocity sensor signal and a recorded vertical velocity sensor signal in dual-sensor seismic streamer data, using a mixture coefficient as a proportionality constant. An upgoing pressure wavefield component is determined as one half of a difference of the recorded pressure sensor signal and the constructed vertical velocity sensor signal, as a function of the mixture coefficient. An error in the upgoing pressure wavefield component is determined by propagating errors in the recorded pressure sensor signal and constructed vertical velocity sensor signal terms. A value of the mixture coefficient is determined that minimizes the error in the upgoing pressure wavefield component.
    Type: Grant
    Filed: May 7, 2008
    Date of Patent: June 7, 2011
    Assignee: PGS Geophysical AS
    Inventor: Neil Turnbull
  • Patent number: 7953556
    Abstract: Methods and apparatus for processing dual sensor (e.g., hydrophone and vertical geophone) data that includes intrinsic removal of noise as well as enhancing the wavefield separation are provided. The methods disclosed herein are based on a decomposition of data simultaneously into dip and frequency while retaining temporal locality. The noise removed may be mainly coherent geophone noise from the vertical geophone, also known as V(z) noise.
    Type: Grant
    Filed: March 4, 2008
    Date of Patent: May 31, 2011
    Assignee: Fairfield Industries Incorporated
    Inventors: Kenneth L. Craft, Josef Paffenholz
  • Patent number: 7944774
    Abstract: A method for marine seismic surveying includes towing seismic sensors in a plurality of streamers in the water, actuating a seismic energy source in the water at selected times and detecting seismic signals at the sensors resulting from the actuation of the source. A data trace is created for each of the detected signals. At least one Fresnel zone is determined for at least some of the seismic data traces. A contribution of each of the traces to each one of a plurality of bins defined in a predetermined pattern is computed, based on the Fresnel zone associated with each trace. Based on the computed contributions, a maximum lateral distance between corresponding seismic sensors is determined that will result in a contribution sum above a selected threshold.
    Type: Grant
    Filed: March 24, 2009
    Date of Patent: May 17, 2011
    Assignee: Apache Corporation
    Inventors: David Monk, Paul G Young
  • Publication number: 20110110188
    Abstract: The technologies described herein include systems and methods for performing a first seismic survey and performing a second seismic survey after a predetermined amount of time has lapsed between the first seismic survey and the second seismic survey. The shot times and the shot positions of the second seismic survey may be substantially the same as the shot times and the shot positions of the first seismic survey. After performing the seismic surveys, seismic data generated by the first seismic survey may be processed to generate a first image, and seismic data generated by the second seismic survey may be processed to generate a second image. After generating the first and second images, a difference between the first image and the second image may be computed to generate a time lapse difference image.
    Type: Application
    Filed: January 21, 2011
    Publication date: May 12, 2011
    Inventors: Johan O. A. Robertsson, Dirk-Jan Van Manen, David Halliday, Robert Laws
  • Publication number: 20110096623
    Abstract: A method of sensing using a phase based transducer in which a transducer response is provided at multiple different levels of sensitivity. The different levels of sensitivity are used to produce an output which does not overscale across a wide range of signal levels. This is particularly useful for use in conjunction with multiplexed arrays of fibre optic sensors for seismic surveying. Methods of sensor calibration and noise reduction are also described.
    Type: Application
    Filed: June 15, 2009
    Publication date: April 28, 2011
    Inventors: Roger Ian Crickmore, Jolyon Defreitas, Philip John Nash
  • Patent number: 7929373
    Abstract: A time-dependent arrival angle is determined at a single receiver station in a towed streamer. Up-going and down-going pressure wavefields are calculated from pressure and vertical particle velocity wavefields measured at the receiver station. Extrapolated up-going and down-going pressure wavefields are generated from the up-going and down-going pressure wavefields displaced by a time delay based upon the time-dependent arrival angle.
    Type: Grant
    Filed: November 19, 2008
    Date of Patent: April 19, 2011
    Assignee: PGS Geophysical AS
    Inventor: Frederick James Barr, Jr.
  • Publication number: 20110085413
    Abstract: A technique includes receiving seismic data acquired by an array of seismic sensors during a towed marine survey of a subsurface and performing migration velocity analysis to determine a background velocity model of the subsurface based at least in part on particle motion derived from the seismic data.
    Type: Application
    Filed: October 8, 2009
    Publication date: April 14, 2011
    Inventors: Henk Keers, Phil Kitchenside, Dave Nichols, Susanne Rentsch, Gabriele Busanello
  • Publication number: 20110063946
    Abstract: A marine cable for seismic surveys is described with a plurality of ceramic pressure sensors arranged in groups of at least two pressure sensors with a group output being representative of the vertical pressure gradient at the group location, and an inclinometric system including one or more transducers for determining the orientation of the sensors of the group in order to determine their true vertical separation.
    Type: Application
    Filed: November 16, 2010
    Publication date: March 17, 2011
    Applicant: WesternGeco LLC
    Inventors: Everhard Johan Muyzert, James Edward Martin, Robert Montgomery Laws, Philip Andrew Felton Christie
  • Publication number: 20110063947
    Abstract: Method for acquiring zero offset data from a marine seismic survey. Seismic data are recorded using source signature monitor receivers located very near the air guns or other sources (81). The recorded data are sorted into common-source gathers (82). A common trace is computed that is common to each gather (83). The common trace is subtracted from each trace in each gather (84), resulting in approximately zero-offset data.
    Type: Application
    Filed: January 28, 2010
    Publication date: March 17, 2011
    Inventor: Michael W. Norris
  • Publication number: 20110038226
    Abstract: Remote seismic surveying systems and methods are disclosed. At least some embodiments illuminate a water or ground surface with a beam from a coherent electromagnetic wave source. Reflected electromagnetic energy is focused onto an image plane where it combines with a reference beam to form an interference pattern. Electronics track the intensity versus time for multiple points in the image and derive displacement signals for various physical locations in the survey region. These displacement signals are associated with seismic source firing times and locations before being stored as seismic traces in a survey database. Some variations use the reflected electromagnetic energy to create multiple interference patterns that vary due to different path length differences, thereby eliminating signal phase ambiguities.
    Type: Application
    Filed: August 12, 2009
    Publication date: February 17, 2011
    Inventor: Gary Lee Scott
  • Publication number: 20110038225
    Abstract: A method for generating seismic energy for subsurface surveying include operating a first seismic vibrator above an area of the subsurface to be surveyed and operating at least a second seismic vibrator above the area substantially contemporaneously with the operating the first seismic vibrator. The first and the second vibrators each have a different selected frequency response. The first and second vibrators each is operated by a same direct sequence spread spectrum signal, wherein a different number of modulation operations for each logical value in the direct sequence spread spectrum signal is selected for each vibrator.
    Type: Application
    Filed: August 12, 2009
    Publication date: February 17, 2011
    Inventor: Stig Rune Lennart Tenghamn
  • Publication number: 20110038227
    Abstract: An embodiment of the invention relates to a method of processing seismic data comprising a plurality of traces, each trace having a source position, a receiver position and a midpoint position, each having coordinates in an inline direction and a crossline direction. The invention uses a data set comprising traces having one of the source position, the receiver position or the midpoint position having coordinates which are invariant in one of the inline or the crossline directions. A non-iterative surface related multiple attenuation algorithm is applied to the data set which assumes substantial non-variation of depth of reflectors in the same one of the inline or the crossline directions.
    Type: Application
    Filed: November 18, 2008
    Publication date: February 17, 2011
    Applicant: WesternGeco LLC
    Inventors: Clement Kostov, Martin Musil, Henrik Bernth
  • Publication number: 20110032794
    Abstract: The present invention provides an undersea seismic monitoring network, the monitoring network comprises at least one underwater vehicle and at least two monitoring stations located on the seabed, where each of the monitoring stations comprises at least one sensor for gathering seismic data and a radio modem for transmitting and receiving data to and from the underwater vehicle via a first wireless connection and where a second wireless connection is established between the monitoring stations, wherein the first wireless connection is formed by electromagnetic radiation through the water and the second wireless connection is formed by the propagation of an electromagnetic signal at least partially through the seabed.
    Type: Application
    Filed: December 8, 2009
    Publication date: February 10, 2011
    Inventors: Mark Rhodes, Brendan Hyland
  • Publication number: 20110032795
    Abstract: A technique facilitates the acquisition of seismic data at a substantially reduced source volume. The methodology generally comprises conducting a seismic survey with seismic sources that have a reduced source volume to collect seismic data. The low frequency data which is lost due to the reduced source volume is replaced with data acquired from a complementary method, such as a receiver-side acquisition method. The two sets of data are combined to provide a comprehensive seismic survey image without requiring conventional seismic source volume.
    Type: Application
    Filed: January 20, 2010
    Publication date: February 10, 2011
    Inventors: Julian Edward Kragh, Robert Laws, Jon-Fredrik Hopperstad
  • Publication number: 20110032796
    Abstract: An improved system and method for seismic exploration using live steam involves creating a cavity of live steam in a body of water, the cavity of live steam imploding due to the water cooling the live steam thereby producing an acoustic pulse, receiving reflections of the acoustic pulse at one or more receivers, and processing the reflections of the acoustic pulse. The cavity of live steam can be created by controlling release valves to introduce live steam into the body of water or by introducing hydrogen and at least one of oxygen or air into the water to create a bubble and then igniting the bubble.
    Type: Application
    Filed: July 30, 2010
    Publication date: February 10, 2011
    Applicant: Cedar Ridge Research, LLC
    Inventor: Larry W. Fullerton
  • Patent number: 7881154
    Abstract: Seismic processing method, in which, in order to eliminate multiple reflections on seismic data, seismic data are migrated in time or in depth (110) arid the data thus migrated are processed to determine an approximation of multiple reflections to be subtracted from, seismic data (120 to 160).
    Type: Grant
    Filed: October 10, 2005
    Date of Patent: February 1, 2011
    Assignee: Cggveritas Services SA
    Inventor: Antonio Pica
  • Patent number: 7872942
    Abstract: A pressure wavefield and a normal velocity wavefield measured on a smoothly shaped acquisition surface by towed dual-sensor marine seismic streamers are decomposed into up-going and down-going pressure and particle velocity components on an observation level between the acquisition surface and a sea surface of undetermined shape. The up-going and down-going pressure and particle velocity components are extrapolated iteratively in steps from the observation level toward the sea surface. An image point and a reflection coefficient of the sea surface at the image point are determined from the iteratively extrapolated up-going and down-going pressure and particle velocity components.
    Type: Grant
    Filed: October 14, 2008
    Date of Patent: January 18, 2011
    Assignee: PGS Geophysical AS
    Inventor: Walter Söllner
  • Patent number: 7869303
    Abstract: A method for identifying a position of a source of noise in a marine seismic record includes defining, for at least one shot record, a set of possible noise source positions. A difference between travel time of noise from each possible noise source position to each of a plurality receiver position for the at least one shot record is determined. Signals from at least a subset of the receiver positions are time-aligned with respect to the difference between travel times for each possible noise source position. The time-aligned signals are then stacked. The noise source position is determined from the stacked, time-aligned signals. This result can then be used to construct a model of the noise at the receiver position.
    Type: Grant
    Filed: August 14, 2007
    Date of Patent: January 11, 2011
    Assignee: PGS Geophysical AS
    Inventor: Jack Dewayne Kinkead
  • Patent number: 7869955
    Abstract: A method of predicting subsurface properties of a geologic formation includes acquiring seismic data for a subsurface region including the geologic formation of interest, computing seismic attributes of the measured seismic data over at least part of this geologic formation, determining internally consistent rock properties representative of the geologic formation, generating models of the same part of the geologic formation with these rock properties, computing synthetic seismic data from the models, computing the same attributes from these synthetic seismic data, and using Bayesian analysis to predict, from the probability of modeled attributes given the models, the probability of the actual subsurface properties given the measured attributes.
    Type: Grant
    Filed: January 30, 2008
    Date of Patent: January 11, 2011
    Assignee: Chevron U.S.A. Inc.
    Inventors: Libo Zhang, Eike F. Rietsch
  • Publication number: 20100322028
    Abstract: A method for controlling output of a marine seismic vibrator includes operating the vibrator using a predetermined driver signal. A vibrator output signal is measured at at least two different places on the vibrator. The at least two measured vibrator output signals are used to determine a corrected driver signal, wherein the corrected driver signal results in fewer harmonics of fundamental frequencies in the vibrator output. The vibrator is operated using the corrected driver signal.
    Type: Application
    Filed: June 23, 2009
    Publication date: December 23, 2010
    Inventor: Stig Rune Lennart Tenghamn
  • Publication number: 20100302901
    Abstract: A technique facilitates the use of seismic data. The technique utilizes an autonomous underwater vehicle to obtain data on water column characteristics in a seismic survey area. The data can be used to adjust aspects of the seismic survey data and/or the seismic survey technique.
    Type: Application
    Filed: May 28, 2009
    Publication date: December 2, 2010
    Inventors: Kenneth E. Welker, Ottar Kristiansen, Morten Svendsen, Julian Edward Kragh
  • Publication number: 20100302902
    Abstract: A marine air gun generates an acoustic signal in water, for example, during a marine seismic survey. The marine air gun includes digital electronic circuitry. The digital electronic circuitry may control an actuator of the marine air gun, digitize and store data from sensors located on or near the marine air gun, send and/or receive digital communications, store and/or output electrical energy, and/or perform other functions. A marine seismic source system that includes multiple air gun clusters may have a separate digital communication link between a command center and each air gun cluster. Each communication link may provide power and digital communication between the command center and one of the air gun clusters.
    Type: Application
    Filed: May 27, 2010
    Publication date: December 2, 2010
    Applicant: Real Time Systems, Inc.
    Inventors: William Allen Nance, Daniel Eugene Hobson
  • Patent number: 7835224
    Abstract: A technique includes obtaining first data indicative of seismic measurements acquired by seismic sensors of a first set of towed streamers and obtaining second data indicative of seismic measurements acquired by seismic sensors of a second set of towed streamers. The second set of towed streamers is towed at a deeper depth than the first set of towed streamers. The technique includes interpolating seismic measurements based on the first and second data. The interpolation includes assigning more weight to the second data than to the first data for lower frequencies of the interpolated seismic measurements.
    Type: Grant
    Filed: March 31, 2008
    Date of Patent: November 16, 2010
    Assignee: WesternGeco L.L.C.
    Inventors: Johan Olof Anders Robertsson, Everhard Muyzert
  • Patent number: 7835223
    Abstract: A technique includes obtaining different sets of data, which are provided by seismic sensors that share a tow line in common. Each data set is associated with a different spatial sampling interval. The technique includes processing the different sets of data to generate a signal that is indicative of a seismic event that is detected by the set of towed seismic sensors. The processing includes using the different spatial sampling intervals to at least partially eliminate noise from the signal.
    Type: Grant
    Filed: April 26, 2007
    Date of Patent: November 16, 2010
    Assignee: WesternGeco L.L.C.
    Inventor: Nicolas Goujon
  • Publication number: 20100238762
    Abstract: A method and apparatus for evaluating submarine formations, such as geological formations located generally under a body of water. Multiple hydrofoils (130), responding to moving water, hydrodynamic, or Bernoulli forces, provide controllable orientation and separation for multiple receivers (135) as they are towed (125) through water (110) in the course of a geophysical survey such as a controlled source electromagnetic survey. The inventive method can be used to provide mutual orthogonality for three antennas in a multiple component electromagnetic receiver.
    Type: Application
    Filed: October 30, 2008
    Publication date: September 23, 2010
    Inventor: Scott C. Hornbostel
  • Patent number: 7800977
    Abstract: The present invention provides a method for pre-stack combining of over/under seismic data. The method includes determining a calibration filter using a first pre-stack marine seismic data set acquired at a first depth and a second pre-stack marine seismic data set acquired at a second depth, wherein the second depth is greater than the first depth and determining a third data set based upon the first pre-stack marine seismic data set, the second pre-stack marine seismic data set, and the calibration filter.
    Type: Grant
    Filed: June 1, 2004
    Date of Patent: September 21, 2010
    Assignee: WesternGeco L.L.C.
    Inventor: Sergio Grion
  • Publication number: 20100226205
    Abstract: A method for survey of hydrocarbon deposits in a researched profile of sea-bottom comprises providing a generator generating pulse electric current with a generator frequency in a towable generator line exciting electric field signals measured by sea-bottom stations synchronized with the generator, forming space-domain data arrays for the generator frequency and for higher odd harmonics frequencies nearest thereto, forming time-domain data arrays for selected offsets, inversion of the time-domain and space-domain data, and determining a bottom strata resistivity and polarization characteristics for the researched profile, based the inversion's results. The inversion preferably encompasses synchronizing and adjusting the generator line and electric field signals, dividing them into a frequency branch, including a fast Fourier transform and a robust summation producing the space-domain arrays, and a time-domain branch, including a robust summation producing the time-domain arrays.
    Type: Application
    Filed: July 6, 2009
    Publication date: September 9, 2010
    Inventors: Andrej Vladimirovich Tulupov, Evgeny Dmitrievich Lisitsyn, Vladimir Eduardovich Kyasper, Alexander Arkad'evich Petrov, Mikhail Sergeevich Malovichko
  • Publication number: 20100226204
    Abstract: A skeg mounts from the stern of a towing vessel and extends below the waterline. A channel in the skeg protects cables for steamers and a source of a seismic system deployed from the vessel. Tow points on the skeg lie below the water's surface and connect to towlines to support the steamers and source. A floatation device supports the source and tows below the water's surface to avoid ice floes. The streamers can have vehicles deployed thereon for controlling a position on the streamer. To facilitate locating the streamers, these vehicles on the streamers can be brought to the surface when clear of ice floes so that GPS readings can be obtained and communicated to a control system. After obtaining readings, the vehicles can be floated back under the surface. Deploying, using, and retrieving the system accounts for ice at the surface in icy regions. In addition, handling the seismic record can account for noise generated by ice impact events.
    Type: Application
    Filed: March 8, 2010
    Publication date: September 9, 2010
    Applicant: ION GEOPHYSICAL CORPORATION
    Inventors: Joseph R. Gagliardi, Shawn Rice, Curt Schneider, Jeffrey W. Cunkelman, Tim Dudley, Dale Lambert, Mike Burnham
  • Patent number: 7782708
    Abstract: A method of filtering seismic signals is described using the steps of obtaining the seismic signals generated by activating a seismic source and recording signals emanating from the source at one or more receivers; defining a source signature deconvolution filter to filter the seismic signal, wherein the filter is scaled by a frequency-dependent term based on an estimate of the signal-to-noise (S/N) based on the spectral power of a signal common to a suite of angle-dependent far-field signatures normalized by the total spectral power of the signatures within the angular suite and performing a source signature deconvolution using the source signature deconvolution filter.
    Type: Grant
    Filed: May 6, 2009
    Date of Patent: August 24, 2010
    Assignee: WesternGeco LLC
    Inventors: Philip Christie, Zoe Lunnon
  • Publication number: 20100202250
    Abstract: A technique includes receiving seismic data, which are indicative of pressure measurements and pressure gradient measurements acquired in a seismic survey of at least one subterranean formation. The technique includes modeling an image of the subterranean formation(s) as a function of the pressure measurements and the pressure gradient measurements. The technique includes determining the image based on the modeling.
    Type: Application
    Filed: February 6, 2009
    Publication date: August 12, 2010
    Inventors: Phil Kitchenside, Gabriele Busanello, Henk Keers
  • Publication number: 20100182873
    Abstract: A first weighted integral operator is applied to dual-sensor data to extrapolate the dual-sensor data to a first position above an acquisition surface, generating extrapolated data. A second weighted integral operator is applied to the extrapolated data to extrapolate the extrapolated data to a second position, generating wavefield separated data. One of the integral operators is applied to a scaled combination of the dual sensor data.
    Type: Application
    Filed: January 20, 2009
    Publication date: July 22, 2010
    Inventor: Tilman Kluver
  • Patent number: 7760586
    Abstract: A device and method for determining bottom sediment is provided. The method includes transmitting a pulse of a pulse width corresponding to a water-bottom depth, extracting a series of amplitude data of water-bottom echo signals from predetermined signals among the water-bottom echo signals received by the transducer at a predetermined time interval, normalizing the extracted series of amplitude data after TVG-processed, calculating two or more feature quantities based on the normalized series of amplitude data in each of segments of the normalized series of amplitude data, and a value corresponding to the water-bottom depth, and generating bottom-sediment classification information indicating the bottom sediment based on the two or more feature quantities.
    Type: Grant
    Filed: April 28, 2008
    Date of Patent: July 20, 2010
    Assignees: The University of Tokyo, Furuno Electric Company Limited
    Inventors: Teruhisa Komatsu, Akira Okunishi, Nicolas Borrallo, Takeharu Yamaguchi
  • Publication number: 20100172208
    Abstract: A system includes a seismic streamer, which includes particle motion sensors and processors. Each processor is associated with a different one of the particle motion sensors and is adapted to process data acquired by the associated particle motion sensor to compensate the data for a characteristic of the sensor.
    Type: Application
    Filed: January 7, 2009
    Publication date: July 8, 2010
    Inventors: Ashok Belani, Kemal Ozdemir, Vidar Husom, Hans Paulson, Nicolas Goujon
  • Publication number: 20100142318
    Abstract: Various methods for simulating up-going pressure wavefield data. In one implementation, a processing apparatus may receive pressure data from pressure sensors that may be installed on a first and second streamer of an over/under streamer pair. The processing apparatus may also receive velocity data from velocity sensors that may be installed on the second streamer of the over/under streamer pair. Using the pressure and velocity data obtained from the sensors installed on each streamer, the processing apparatus may simulate the pressure and velocity data that would have been obtained by a streamer in a calm sea at a depth equal to the vertical distance between the first and second streamers. The simulated pressure and velocity data may then be combined to estimate the up-going pressure wavefield data.
    Type: Application
    Filed: December 10, 2008
    Publication date: June 10, 2010
    Inventor: Ralf G. Ferber
  • Publication number: 20100135113
    Abstract: A method for determining quality of signals acquired using marine seismic streamers having pressure responsive sensors and motion responsive sensors includes cross ghosting pressure responsive seismic signals and contemporaneously acquired motion responsive seismic signals. First filters are determined that cause the cross ghosted pressure responsive signals to substantially match the cross ghosted motion responsive signals. Second filters are determined that cause the cross ghosted motion responsive signals to substantially match the cross ghosted pressure responsive signals. The first and second filters are convolved and the convolution is used to determine signal quality.
    Type: Application
    Filed: December 3, 2008
    Publication date: June 3, 2010
    Inventor: Guillaume Cambois
  • Publication number: 20100118646
    Abstract: A method for generating seismic energy for subsurface surveying includes operating a first seismic vibrator and operating at least a second seismic vibrator substantially contemporaneously with the operating the first seismic vibrator. A driver signal to each of the first and the at least a second seismic vibrators that are substantially uncorrelated with each other.
    Type: Application
    Filed: November 7, 2008
    Publication date: May 13, 2010
    Inventor: Stig Rune Lennart Tenghamn
  • Patent number: 7715988
    Abstract: A technique includes obtaining particle motion data and pressure data that are acquired by seismic sensors while in tow. The sensors are part of a plurality of streamers, and the pressure and particle motion data contain surface ghosts. The technique includes processing the particle motion data and the pressure data to generate a data set that is indicative of a pressure wavefield at positions between the streamers and is substantially free of the surface ghosts.
    Type: Grant
    Filed: June 13, 2007
    Date of Patent: May 11, 2010
    Assignee: WesternGeco L.L.C.
    Inventors: Johan Olof Anders Robertsson, Philippe Caprioli, Ahmet Kemal Ozdemir
  • Publication number: 20100110830
    Abstract: There is provided a method of direct waveform inversion of turning waves (311, 312, 313) to determine parameters characterizing properties of the earth or sub-sections of the earth, particularly of parts of the earth which are capable of trapping hydrocarbons with the inversion yielding from the wavefield of turning waves information representing or being equivalent to velocities or slownesses and/or the gradient of velocities or slownesses, particularly by evaluating wavefield data in the vicinity of turning points (33). The method can be applied sequentially as a survey sinking method.
    Type: Application
    Filed: August 21, 2007
    Publication date: May 6, 2010
    Inventor: Colin Thomson
  • Publication number: 20100103772
    Abstract: A method of conducting multiple source, multiple signal seismic surveys in a marine environment are provided.
    Type: Application
    Filed: October 22, 2009
    Publication date: April 29, 2010
    Applicant: CONOCOPHILLIPS COMPANY
    Inventors: Peter M. EICK, Joel D. BREWER, Stephen K. CHIU
  • Publication number: 20100097885
    Abstract: A technique includes providing seismic data that is indicative of energy that is sensed in response to a first operation of at least one seismic source in a first seismic survey and a second operation of at least one seismic source in a second seismic survey. The technique includes processing the seismic data to determine a timing of the second operation relative to the first operation, and the technique includes based at least in part of the determined timing, processing the seismic data to generate a dataset, which is indicative of the sensed energy that is attributable to the first operation and is not attributable to the second operation.
    Type: Application
    Filed: October 22, 2008
    Publication date: April 22, 2010
    Inventor: Ian Moore
  • Publication number: 20100097886
    Abstract: A method for estimating formation quality factor includes determining an upgoing pressure wavefield of seismic signals recorded using a collocated pressure responsive sensor and motion responsive sensor deployed in a body of water The upgoing wavefield has spectral effect of water surface ghosting attenuated by combining the pressure responsive signals and motion responsive signals. The quality factor is determined by determining a difference in amplitude spectra between a first seismic event and a second seismic event in the upgoing pressure wavefield.
    Type: Application
    Filed: October 20, 2008
    Publication date: April 22, 2010
    Inventors: Anthony James Day, Guillaume Cambois
  • Patent number: 7684281
    Abstract: Signals of pressure sensors and particle motion sensors located in marine seismic streamers are combined to generate a seismic wavefield. At least a part of the particle motion sensor signal is calculated from a recorded pressure signal and the calculated at least a part of the particle motion sensor signal is used to generate a particle motion sensor signal in which noise is substantially attenuated in at least a lower frequency range thereof. The pressure sensor data and the noise attenuated particle motion sensor signal can then be combined to calculate up- and down-going wavefields.
    Type: Grant
    Filed: April 14, 2008
    Date of Patent: March 23, 2010
    Assignee: PGS Americas, Inc.
    Inventors: Svein Torleif Vaage, Stig Rune Lennart Tenghamn, Claes Nicolai Borresen
  • Patent number: 7679991
    Abstract: A method for processing seismic data acquired using a first over/under streamer and a second over/under streamer. In one implementation, the method may include estimating seismic data that would have been acquired by a third over/under streamer disposed at a depth equivalent to a distance separating the first over/under streamer from the second over/under streamer; and applying a dephase and sum algorithm to seismic data acquired by the first over/under streamer and the second over/under streamer and the estimated seismic data.
    Type: Grant
    Filed: March 16, 2007
    Date of Patent: March 16, 2010
    Assignee: WesternGeco L. L. C.
    Inventor: Ralf Ferber
  • Patent number: 7664602
    Abstract: A method for the quantitative characterization of a seabed sediment composition and a seabed's layered subbottom structure from at least one normal-incidence, single-channel reflection acoustic amplitude time series seismogram is disclosed. The method detects a plurality of reflections from subbottom interfaces in said seismograms, determines the traveltime, the polarity and the reflectivity of each detected reflection, determines the intrinsic attenuation of the sediment layer between pairs of adjacent reflections, and determines the acoustic properties, layer thicknesses and material properties of the seabed's layered subbottom structure as a function of said traveltimes, polarities and reflectivities of the detected reflections and said intrinsic attenuation of the sediment layer between pairs of adjacent reflections. A forward model describing the physical relationship between the material properties and the acoustic properties of seabed sediments is also disclosed.
    Type: Grant
    Filed: February 23, 2007
    Date of Patent: February 16, 2010
    Assignee: National University of Ireland, Galway
    Inventors: Klaus Christian Leurer, Colin Brown