Dynamic Timing Correction Patents (Class 367/51)
  • Patent number: 10234580
    Abstract: Seismic data recorded by subsurface seismic sensors placed in a borehole, such as an oil or gas well, are transformed via a process of upward wavefield propagation to pseudo-receivers at the surface of the earth. The seismic data thus transformed can be processed as though the data had been recorded by the pseudo-receivers at the surface rather than in the borehole where the data were actually recorded. This method accurately accounts for seismic source statics, anisotropy, and all velocity effects between the real receivers in the borehole and the pseudo-receivers at the surface of the earth.
    Type: Grant
    Filed: January 19, 2016
    Date of Patent: March 19, 2019
    Inventors: Brian Nelson Fuller, John Marcus Sterling
  • Patent number: 9971050
    Abstract: Various examples are provided for generalized internal multiple imaging (GIMI). In one example, among others, a method includes generating a higher order internal multiple image using a background Green's function and rendering the higher order internal multiple image for presentation. In another example, a system includes a computing device and a generalized internal multiple imaging (GIMI) application executable in the computing device. The GIMI application includes logic that generates a higher order internal multiple image using a background Green's function and logic that renders the higher order internal multiple image for display on a display device. In another example, a non-transitory computer readable medium has a program executable by processing circuitry that generates a higher order internal multiple image using a background Green's function and renders the higher order internal multiple image for display on a display device.
    Type: Grant
    Filed: May 28, 2014
    Date of Patent: May 15, 2018
    Assignee: KING ABDULLAH UNIVERSITY OF SCIENCE AND TECHNOLOGY
    Inventors: Mohammad Akbar Hosain Zuberi, Tariq Alkhalifah
  • Patent number: 9945969
    Abstract: A method, an apparatus and a computer-readable medium for processing seismic data are provided. The method includes selecting well-imaged areas of a sediment-to-salt interface, and performing (1) a dual-flood RTM with prismatic waves to identify new areas of the sediment-to-salt interface, and (2) one or more RTM to identify other new areas of the sediment-to-salt interface or of a salt-to-sediment interface.
    Type: Grant
    Filed: September 7, 2012
    Date of Patent: April 17, 2018
    Assignee: CGG SERVICES SAS
    Inventors: Yunfeng Li, Yogesh Agnihotri, Timmy Dy
  • Patent number: 9684089
    Abstract: A method comprises obtaining vertical seismic profile (VSP) data using seismic sources positioned at corresponding shot locations at desired offsets from seismic receivers positioned in a borehole drilled through a formation. The method further comprises receiving seismic waves emanating from the seismic sources, processing the VSP data to determine vertical slowness of the formation, and analyzing an azimuthal anisotropy of the formation. This is performed by calculating modified total slowness of the formation using the vertical slowness and vertical polarization angle, calculating and applying a polar anisotropy correction to the modified total slowness to obtain a corrected value of the modified total slowness, and normalizing the corrected modified total slowness to a desired polarization angle.
    Type: Grant
    Filed: November 23, 2015
    Date of Patent: June 20, 2017
    Assignee: Halliburton Energy Services, Inc.
    Inventor: Ran Zhou
  • Patent number: 9244181
    Abstract: A method for processing seismic data. The method includes predicting seismic data according to an earth model representing seismic properties of subterranean formations in the earth, determining a difference between seismic data acquired from one or more seismic receivers and the predicted seismic data, projecting the difference into a model space in traveltime, and updating the earth model according to the projected difference. As a result, the updated earth model more accurately represents the seismic properties of subterranean formations in the earth.
    Type: Grant
    Filed: October 19, 2009
    Date of Patent: January 26, 2016
    Assignee: WesternGeco L.L.C.
    Inventors: James Rickett, Paul Childs
  • Patent number: 8635041
    Abstract: Described herein are implementations of various technologies for a method for configuring a seismic data acquisition network. A first message may be received from a first node of the seismic data acquisition network over a first direct communication link. The first message may comprise a first precision quality of a first reference clock to which the first node may be synchronized. A second message may be received from a second node of the seismic data acquisition network over a second direct communication link. The second message may comprise a second precision quality of a second reference clock to which the second node may be synchronized. One of the first precision quality and the second precision quality may be determined to have a higher precision quality. A real time clock may be synchronized to one of the first reference clock and second reference clock having the higher precision quality.
    Type: Grant
    Filed: June 11, 2009
    Date of Patent: January 21, 2014
    Assignee: WesternGeo L.L.C.
    Inventors: Daniel Golparian, Anh Duc Dao
  • Patent number: 8605543
    Abstract: A wireless seismic data acquisition unit with a wireless receiver providing access to a common remote time reference shared by a plurality of wireless seismic data acquisition units in a seismic system. The receiver is capable of replicating local version of remote time epoch to which a seismic sensor analog-to-digital converter is synchronized. The receiver is capable of replicating local version of remote common time reference for the purpose of time stamping local node events. The receiver is capable of being placed in a low power, non-operational state over periods of time during which the seismic data acquisition unit continues to record seismic data, thus conserving unit battery power. The system implements a method to correct the local time clock based on intermittent access to the common remote time reference. The method corrects the local time clock via a voltage controlled oscillator to account for environmentally induced timing errors.
    Type: Grant
    Filed: October 25, 2007
    Date of Patent: December 10, 2013
    Assignee: Fairfield Industries Incorporated
    Inventors: Clifford H. Ray, Glenn D. Fisseler, William Guyton
  • Patent number: 8594962
    Abstract: A technique includes determining a first difference between a time that a first network element of a seismic acquisition network receives a first frame pulse from a second network element of the seismic acquisition network and a time that the first network element transmits a second frame pulse to the second network element. The technique includes determining a second difference between a time that the second network element receives the second frame pulse and a time that the second network element transmits the first frame pulse. The technique includes determining a transmission delay between the first and second network elements based on the first and second time differences.
    Type: Grant
    Filed: May 28, 2009
    Date of Patent: November 26, 2013
    Assignee: WesternGeco L.L.C.
    Inventor: Geir A. M. Drange
  • Publication number: 20130182537
    Abstract: Computing device and method for calculating time-shifts associated with travel-times of seismic waves emitted by a source and recorded by plural seismic detectors after reflection from a subsurface structure. The method includes receiving seismic data (d) that includes plural traces related to a subsurface, wherein the seismic data (d) is in a time-space domain; transforming with a processor the seismic data (d) from the time-space domain to a radon domain; picking linear events from the seismic data in the radon domain; calculating the time-shifts associated with the picked linear events; correcting the seismic data (d) based on the time-shifts to obtain new seismic data (d?); and computing an image of the subsurface based on the new seismic data (d?). The time-shifts are calculated per trace and per event.
    Type: Application
    Filed: January 11, 2013
    Publication date: July 18, 2013
    Applicant: CGGVERITAS SERVICES SA
    Inventor: CGGVERITAS SERVICES SA
  • Publication number: 20130088940
    Abstract: Computing device, software and method for identifying a source mechanism associated with a microseismic event taking place in a subsurface of the earth. The method includes receiving traces associated with a plurality of receivers located in a grid above the subsurface; dividing the grid in a set of sub-blocks, determining, for each sub-block, a corresponding summation element based on traces associated with the corresponding sub-block; identifying a predetermined number of patterns that are associated with plural source mechanisms; multiplying each summation element by a polarization coefficient according to a corresponding pattern; calculating for each pattern, a semblance function based on summation elements of the sub-blocks; and identifying the source mechanism of the microseismic event based on the semblance function.
    Type: Application
    Filed: August 23, 2012
    Publication date: April 11, 2013
    Applicant: CGGVERITAS SERVICES SA
    Inventor: Benoit DE CACQUERAY
  • Patent number: 8395967
    Abstract: A walkaway VSP survey is carried out with receivers located in a borehole under a salt overhang. Redatuming of the multicomponent data to virtual sources in the borehole followed by vector Kirchhoff migration using a simple velocity model provides an accurate image of the salt face.
    Type: Grant
    Filed: May 29, 2009
    Date of Patent: March 12, 2013
    Assignee: Baker Hughes Incorporated
    Inventors: Min Lou, Francis D. Doherty, James C. Jackson
  • Patent number: 8329284
    Abstract: Identification devices are known, e.g. in the form of labels to be attached by sewing or adhesive, monograms and the like, for the individualizing identification of items of clothing, shoes, shoe inserts or similar personal objects to be worn on a person's body. Whenever such identification devices are easy to read and to manufacture, they usually have relatively little recognition value. It is proposed to provide an identification device with, or to produce it in the form of, an image of a pressure-distribution pattern obtained by at least two-dimensional sampling of a pressure distribution between a part of the person's body and a substantially solid object.
    Type: Grant
    Filed: July 16, 2003
    Date of Patent: December 11, 2012
    Inventor: Peter Seitz
  • Patent number: 8259531
    Abstract: A method is disclosed for reflection time shift matching a first and a second set of seismic reflection data (10,30) comprising first and second seismic reflection traces (1,3) with series of generally corresponding seismic reflections (11,31). The second set of seismic data (30) comprises at least one laterally extending series (40) of new seismic events (4) not present in the first set of seismic data (10). Reflection time shifts (22) are calculated as required for matching seismic reflections (31) of the second reflection traces (3) of the second seismic reflection data (30) with corresponding seismic reflections (11) of the first reflection traces (1). The calculation of the time shifts (22) are made by calculating coefficients of basis function estimates such as Legendre polynomials in order to save calculation effort.
    Type: Grant
    Filed: March 31, 2009
    Date of Patent: September 4, 2012
    Assignee: Statoil ASA
    Inventor: Espen Oen Lie
  • Patent number: 8144543
    Abstract: The invention relates to a method of processing seismic data, the said seismic data comprising a gather of seismic traces organized according to one or several acquisition parameters, comprising the steps of: a) defining an equation for an RMO curve as a combination of elementary functions of the acquisition parameter(s), b) determining an RMO curve from the equation of step (a) as a combination of orthogonal elementary functions c) for a given time or at a given depth, determining the coefficients of the combination that optimize the semblance of traces along the RMO curve.
    Type: Grant
    Filed: June 30, 2010
    Date of Patent: March 27, 2012
    Assignee: CGG Veritas SA
    Inventors: Risto Siliqi, Philippe Herrmann
  • Publication number: 20110317520
    Abstract: A system for acquiring seismic data over sand dune surfaces is provided. The system includes a seismic wave generator for emitting a plurality of seismic signals into the Earth in an area covered by sand dunes. The system also includes a sand streamer for acquiring seismic data over the sand dune surfaces, such that the sand streamer includes a plurality of geophones. The plurality of geophones receive a plurality of wave signals transmitted from a subsurface corresponding to the sand dune surface, in response to emission of the plurality of seismic signals to the area of the sand dune surface by the seismic wave generator. Each geophone of the plurality of geophones is mounted on a panel wherein, one or more sides of the panel are coupled loosely to one or more rigid plates. The one or more rigid plates provide stability and mobility to assembly of panels and the plurality of geophones, thereby enabling the sand streamer to move efficiently over the surface of the sand dune.
    Type: Application
    Filed: June 29, 2010
    Publication date: December 29, 2011
    Applicant: KING ABDUL AZIZ CITY FOR SCIENCE AND TECHNOLOGY
    Inventors: TARIQ ALI ALKHALIFAH, Hashim Sari Almalki
  • Publication number: 20110090759
    Abstract: Various technologies for a seismic acquisition system, which may include an acquisition central system configured to determine a desired start time for a sweep cycle in one or more vibrators and a recorder source system controller in communication with the acquisition central system. The recorder source system controller may be configured to receive the desired start time from the acquisition central system. The seismic acquisition system may further include one or more vibrator units in communication with the recorder source system controller. Each vibrator unit may be configured to start a sweep cycle in a vibrator at the desired start time.
    Type: Application
    Filed: December 22, 2010
    Publication date: April 21, 2011
    Inventor: Martin Laycock
  • Patent number: 7894299
    Abstract: Method for designing a converted mode (PS or SP) seismic survey to accomplish specified vertical and lateral resolution objectives at target depth. An equation (181) is provided for determining the minimum bandwidth required for a desired vertical resolution at a selected scattering angle, as a function of incident and reflected wave velocities, one of which is the P-wave velocity and the other is the S-wave velocity. A second equation (182) is provided for determining migration acceptance angle from the desired vertical and lateral resolutions. Source and receiver apertures may then be determined by ray tracing. Finally, a third equation (183) is provided for the maximum bin size to avoid aliasing, given the migration acceptance angle and a maximum frequency needed to achieve the bandwidth requirement. Source and receiver spacing may then be based on the maximum bin size.
    Type: Grant
    Filed: June 27, 2007
    Date of Patent: February 22, 2011
    Assignee: ExxonMobil Upstream Research Co.
    Inventor: Mark A. Meier
  • Patent number: 7830747
    Abstract: Three data subsets are obtained in three selected azimuthal directions from seismic data in heterogeneous, anisotropic media. Azimuthal velocities are determined for each of the data subsets. A linear system of equations in the three selected azimuthal directions and the three determined azimuthal velocities is solved for three independent parameters. An azimuthal time migration velocity function is constructed from the three solved independent parameters. A time migration traveltime function is constructed from the constructed azimuthal time migration velocity function.
    Type: Grant
    Filed: November 1, 2006
    Date of Patent: November 9, 2010
    Assignee: PGS Geophysical AS
    Inventor: Walter Söllner
  • Patent number: 7804739
    Abstract: The invention relates to a method of processing seismic data, the said seismic data comprising a gather of seismic traces organised according to one or several acquisition parameters, comprising the steps of: a) defining an equation for an RMO curve as a combination of elementary functions of the acquisition parameter(s), b) determining an RMO curve from the equation of step (a) as a combination of orthogonal elementary functions c) for a given time or at a given depth, determining the coefficients of the combination that optimise the semblance of traces along the RMO curve.
    Type: Grant
    Filed: April 19, 2006
    Date of Patent: September 28, 2010
    Assignee: CGG Veritas SA
    Inventors: Risto Siliqi, Philippe Herrmann
  • Patent number: 7733741
    Abstract: Time slices of seismic data are transformed from rectangular space-time domain to cylindrical space-time domain. 2-D seismic migration is performed on the transformed data for each radial direction. Slices of the migrated data are inverse transformed back to the rectangular space-time domain, generated migrated 3-D data for generally inhomogeneous media.
    Type: Grant
    Filed: April 5, 2007
    Date of Patent: June 8, 2010
    Assignee: PGS Geophysical AS
    Inventor: Naide Pan
  • Patent number: 7701804
    Abstract: A method for constructing a model representative of a heterogeneous medium from data expressed in different time scales with application to hydrocarbon characterization. The method first estimates sequentially, from the data expressed in each different time scale, parameters or physical quantities of the model, described for each different time scale. Second, a scale factor allowing conversion of a model described in a time scale into a model described in another time scale is determined. This determination is carried out by minimizing the dissimilarity between a parameter estimated in a time scale and this parameter estimated in the other time scale. Finally, estimation of a single model is performed, by taking simultaneously an account of the data expressed in the various time scales, and using the scale factor found previously for the time scale conversions.
    Type: Grant
    Filed: August 2, 2005
    Date of Patent: April 20, 2010
    Assignee: Institut Francais du Petrole
    Inventors: Yohan Agullo, Danièle Mace-Prieur, Thierry Tonellot, Marc Lavielle
  • Publication number: 20090122644
    Abstract: A method and a system for determining the position of a drill bit are presented. The method comprises determining positions of seismic wave detectors, recording seismic waves generated at the drill bit, identifying events at the drill bit, determining a plurality of relative positions of the drill bit, and determining, based at least partly on a starting position and a sum of the relative positions, an absolute position of the drill bit. The method further comprises determining a position of the drill bit at a second event in relation to a position of the drill bit at a first event, and determining a second seismic wave propagation velocity between the drill bit and at least one of the detectors, based at least partly on the determined position of the drill bit at the second event.
    Type: Application
    Filed: January 23, 2006
    Publication date: May 14, 2009
    Inventor: Jan Hjorth
  • Patent number: 7525874
    Abstract: A method is used to convert seismic data between bounding upper and lower surfaces in the time domain to the depth domain. An upper depth surface corresponding to the upper time surface is determined, either from well data or by time-depth conversion of the upper time surface. An interval velocity value is determined for each seismic sample between the bounding time surfaces from velocity data generated from well logs. The seismic times between the bounding time surfaces are then converted to the depth domain by adding the thickness of each seismic sample to the upper depth surface, wherein the thickness of each seismic sample is a function of the seismic sample rate and interval velocity value for each seismic sample. The seismic attribute values from the converted seismic data can be interpolated to a linear depth sampling.
    Type: Grant
    Filed: April 17, 2007
    Date of Patent: April 28, 2009
    Assignee: Prism Seismic Inc.
    Inventors: Gary Charles Robinson, Volodya Litvinov, Udo G. Araktingi
  • Publication number: 20090080290
    Abstract: A wireless seismic data acquisition unit with a wireless receiver providing access to a common remote time reference shared by a plurality of wireless seismic data acquisition units in a seismic system. The receiver is capable of replicating local version of remote time epoch to which a seismic sensor analog-to-digital converter is synchronized. The receiver is capable of replicating local version of remote common time reference for the purpose of time stamping local node events. The receiver is capable of being placed in a low power, non-operational state over periods of time during which the seismic data acquisition unit continues to record seismic data, thus conserving unit battery power. The system implements a method to correct the local time clock based on intermittent access to the common remote time reference. The method corrects the local time clock via a voltage controlled oscillator to account for environmentally induced timing errors.
    Type: Application
    Filed: October 25, 2007
    Publication date: March 26, 2009
    Inventors: Clifford H. Ray, Glenn D. Fisseler, William Guyton
  • Patent number: 7460437
    Abstract: A method and system for seismic data processing utilizes azimuthal variations in the velocity of seismic signals. The system and method utilizes a plurality of seismic energy sources that are located at known positions at the surface of the earth. The seismic energy sources generate seismic signals that propagate downward into the earth. Some of the seismic signals are reflected and diffracted by various sub-surface layers and are returned to the surface of the earth. The returned seismic signals are received by a plurality of receivers. The method includes the step of determining the distance from an energy source to an image point. A fast travel time of the seismic signal from the energy source to the image point is determined, and a slow travel time of the seismic signal from the energy source to the image point is determined. The azimuth angle between the energy source and the surface location of the image point is calculated.
    Type: Grant
    Filed: January 3, 2007
    Date of Patent: December 2, 2008
    Assignee: Weinman GeoScience
    Inventors: Charles Sicking, Stuart Nelan, William “Bill” H. McLain
  • Patent number: 7447113
    Abstract: A method is disclosed for migrating seismic data which includes determining travel time of a compressional wave from a source location to a scatter point, taking into account ray bending. Travel time of a shear wave from the scatter point to a receiver location is determined, taking into account ray bending at the interfaces between subsurface strata. The determined travel times are then used to migrate the seismic data. In one embodiment, the travel times take account of vertically transversely isotropic media with a vertical symmetry axis.
    Type: Grant
    Filed: October 5, 2004
    Date of Patent: November 4, 2008
    Assignee: PGS Americas, Inc.
    Inventors: Ruben D. Martinez, Chuanwen Sun
  • Patent number: 7388808
    Abstract: A method is disclosed for depth migrating seismic data. The method includes pre-stack time migrating the seismic data to form a stacked, time migrated image. The stacked, time migrated image is demigrated, and post-stack depth migration is then performed on the demigrated image. In some embodiments, the pre-stack time migration and the demigration account for ray bending in vertically transversely isotropic media.
    Type: Grant
    Filed: September 23, 2004
    Date of Patent: June 17, 2008
    Assignee: PGS Americas, Inc.
    Inventors: Shu-Schung Lee, John Willis, Yeashung Lin
  • Publication number: 20080137478
    Abstract: Three data subsets are obtained in three selected azimuthal directions from seismic data in heterogeneous, anisotropic media. Azimuthal velocities are determined for each of the data subsets. A linear system of equations in the three selected azimuthal directions and the three determined azimuthal velocities is solved for three independent parameters. An azimuthal time migration velocity function is constructed from the three solved independent parameters. A time migration traveltime function is constructed from the constructed azimuthal time migration velocity function.
    Type: Application
    Filed: November 1, 2006
    Publication date: June 12, 2008
    Inventor: Walter Sollner
  • Patent number: 7355923
    Abstract: System and method for performing anisotropy corrections of post-imaging seismic data for a subsurface formation. The method may receive seismic data, preferably pre-stack seismic data comprising a plurality of traces, e.g., collected from a plurality of source and receiver locations. The seismic data may be imaged/migrated to produce imaged seismic data, which is organized into an arrangement that preserves aspects of the relative seismic propagation angle in the subsurface. One or more anisotropic parameters and corresponding corrections may be determined by analyzing the organized imaged seismic data. The determined parameters or corrections may be used to correct at least a subset of the imaged seismic data, thereby producing corrected seismic data which is useable in analyzing the formation. The corrected data may then optionally be stacked to produce a collection of corrected stacked traces, and/or analyzed as desired. The pre-stack data and/or the corrected seismic data may optionally be displayed.
    Type: Grant
    Filed: May 11, 2005
    Date of Patent: April 8, 2008
    Assignee: Landmark Graphics Corporation
    Inventors: Moshe Reshef, Murray W. Roth
  • Patent number: 7321526
    Abstract: The present invention provides a method for analyzing traces collected along a plurality of adjacent sail lines in a marine seismic survey area. The method comprises selecting a plurality of trace groups, at least one trace in each group sharing a common midpoint with at least one trace from another group, determining an initial zero-offset travel time for each trace in the trace groups, and generating a plurality of updated zero-offset travel times and a plurality of time corrections for the trace groups using a pre-selected function of the initial zero-offset travel times.
    Type: Grant
    Filed: May 30, 2003
    Date of Patent: January 22, 2008
    Assignee: WesternGeco, L.L.C.
    Inventors: Charles V. Carvill, Jonathan G. Fried
  • Patent number: 7167414
    Abstract: A method is disclosed for amplitude preserving Kirchhoff time migration. The method includes calculating estimates of the geometrical spreading terms using a constant velocity approximation. Takeoff and emergence angles are accurately calculated based on a model of velocity which varies with respect to travel time. An image can be calculated at at least one travel time using the estimated weights and calculated takeoff and emergence angles.
    Type: Grant
    Filed: October 4, 2004
    Date of Patent: January 23, 2007
    Assignee: PGS Americas, Inc.
    Inventors: Seongbok Lee, David Graham King
  • Patent number: 7065004
    Abstract: A method is disclosed for processing seismic data. The method includes prestack depth migrating the seismic data to generate common image gathers using an initial velocity-depth model. Horizons in the migrated seismic data are selected. Residual migration velocity analysis in the depth-offset domain is performed with respect to each selected horizon, and the velocity-depth model is updated based on the residual migration velocity analysis.
    Type: Grant
    Filed: April 22, 2004
    Date of Patent: June 20, 2006
    Assignee: PGS Americas, Inc.
    Inventors: Junru Jiao, Ruben D. Martinez
  • Patent number: 6920084
    Abstract: A method and apparatus for compensating acquired seismic data for the presence of dipping events are disclosed. The method includes migrating the acquired, unstacked seismic data; and spatially mapping the migrated seismic data to correct their respective offsets while maintaining the angle of incidence to a dipping event. The method may be performed by a programmed computing device or encoded as instructions for a computing device on a program storage medium.
    Type: Grant
    Filed: January 15, 2003
    Date of Patent: July 19, 2005
    Assignee: Western Geco, L.L.C.
    Inventor: Scott W MacKay
  • Patent number: 6898148
    Abstract: The present invention provides methods to be used in seismic data processing to address problems encountered during data acquisition. The present invention provides a multi-step process to reduce aliasing of seismic data along time slices.
    Type: Grant
    Filed: March 26, 2003
    Date of Patent: May 24, 2005
    Assignee: WesternGeco, L.L.C.
    Inventor: Scott William MacKay
  • Patent number: 6898147
    Abstract: The invention comprises a system for processing seismic data to estimate time shift resulting from velocity anisotropy in the earth's subsurface. A gather of seismic data traces is formed and selected seismic data traces included in said gather within selected time windows are cross-correlated to estimate the time shift in the seismic data traces included in said gather resulting from velocity anisotropy in the earth's subsurface.
    Type: Grant
    Filed: October 20, 2003
    Date of Patent: May 24, 2005
    Assignee: Input/Output, Inc.
    Inventors: Edward Louis Jenner, Martin Carroll Williams
  • Patent number: 6819628
    Abstract: Seismic imaging apparatus for receiving data propagated through sub-surface structure from a seismic source to at least one seismic receiver and forming an image therefrom, the apparatus comprising: an imager for forming an initial image from said data including initial locations of seismic features indicated in said data, a migrator, associated with said imager, for carrying out seismic migration over at least two layers or depth levels to provide corrections to said initial locations, said migrator comprising a krylov space expander for carrying out a krylov space expansion of the exponent of a square root operator, the operator being for defining a wave propagation between respective layers, and a corrector, for using said corrections with said initial locations to form a seismic image indicating said features.
    Type: Grant
    Filed: April 7, 2003
    Date of Patent: November 16, 2004
    Assignee: Paradigm Geophysical (Luxembourg) S.a.r.l.
    Inventor: Hillel Tal-Ezer
  • Patent number: 6816435
    Abstract: The present invention relates to a method for estimating the position and trajectory of a drill during drilling of boreholes in rock. The method comprising the steps of determining the starting position of the drill bit and recording the received transient seismic waves generated by the drill on impact, and estimating the difference in arrival time between events. From these, the relative distances, between the positions of the drill bit at different events are calculated and from these the present position is calculated.
    Type: Grant
    Filed: September 30, 2002
    Date of Patent: November 9, 2004
    Assignee: Guideline AB
    Inventors: Jan Hjorth, Björn Litzen
  • Publication number: 20040196738
    Abstract: Seismic imaging apparatus for receiving data propagated through sub-surface structure from a seismic source to at least one seismic receiver and forming an image therefrom, the apparatus comprising: an imager for forming an initial image from said data including initial locations of seismic features indicated in said data, a migrator, associated with said imager, for carrying out seismic migration over at least two layers or depth levels to provide corrections to said initial locations, said migrator comprising a krylov space expander for carrying out a krylov space expansion of the exponent of a square root operator, the operator being for defining a wave propagation between respective layers, and a corrector, for using said corrections with said initial locations to form a seismic image indicating said features.
    Type: Application
    Filed: April 7, 2003
    Publication date: October 7, 2004
    Inventor: Hillel Tal-Ezer
  • Patent number: 6798714
    Abstract: A method of performing normal moveout (NMO) correction and stacking of a common-midpoint (CMP) gather of seismic traces in a manner that avoids NMO stretch is disclosed. A CMP gather without NMO correction is modeled as the sum of a series of short overlapping time intervals whose center times follow the NMO curve as it changes with offset. The sample values contained in these intervals are solved simultaneously by performing a statistical fit to the CMP gather based on this model. A CMP stacked trace is formed by summing these intervals at their zero-offset positions at each time sample.
    Type: Grant
    Filed: April 30, 2003
    Date of Patent: September 28, 2004
    Assignee: Kelman Technologies Inc.
    Inventor: Stewart Trickett
  • Patent number: 6791900
    Abstract: A method of calculating a throw volume corresponding to a seismic data volume. A range of time shifts and a search direction for the seismic data volume are selected. A data location separation and a vertical time window are also selected. A cross-correlation is calculated between data values corresponding to first and second data locations separated by the data location separation and symmetrically located in the search direction on each side of a target data location. The cross-correlation is calculated throughout the vertical time window for each time shift in the range of time shifts. The time shift corresponding to the maximum calculated cross-correlation is stored in the throw volume.
    Type: Grant
    Filed: May 6, 2003
    Date of Patent: September 14, 2004
    Assignee: ExxonMobil Upstream Research Company
    Inventors: Dominique G. Gillard, John E. Eastwood, Brian P. West, Theodore G. Apotria
  • Publication number: 20040141414
    Abstract: A method of determination of fluid pressures in a subsurface region of the earth uses seismic velocities and calibrations relating the seismic velocities to the effective stress on the subsurface sediments. The seismic velocities may be keyed to defined seismic horizons and may be obtained from many methods, including velocity spectra, post-stack inversion, pre-stack inversion, VSP or tomography. Overburden stresses may be obtained from density logs, relations between density and velocity, or from inversion of potential fields data. The seismic data may be P-P, P-S, or S-S data. The calibrations may be predetermined or may be derived from well information including well logs and well pressure measurements. The calibrations may also include the effect of unloading. The determined pressures may be used in the analysis of fluid flow in reservoirs, basin and prospect modeling and in fault integrity analysis.
    Type: Application
    Filed: January 9, 2004
    Publication date: July 22, 2004
    Applicant: ConocoPhillips Company
    Inventors: Alan Royce Huffman, Ernest C. Onyia, Richard Wayne Lahann, David W. Bell, Robert Lankston
  • Patent number: 6681184
    Abstract: The invention comprises a system for processing seismic data to estimate time shift resulting from velocity anisotropy in the earth's subsurface. A gather of seismic data traces is formed and selected seismic data traces included in said gather within selected time windows are cross-correlated to estimate the time shift in the seismic data traces included in said gather resulting from velocity anisotropy in the earth's subsurface.
    Type: Grant
    Filed: May 15, 2001
    Date of Patent: January 20, 2004
    Assignee: Input/Output, Inc.
    Inventors: Edward Louis Jenner, Martin Carroll Williams
  • Patent number: 6466873
    Abstract: A method of migrating seismic event data in the presence of a vertically time-varying velocity field defined by a migration velocity function is provided. The method comprises approximating a migration velocity function by constant stepwise stage velocities. The seismic event data is time stretched and is then successively migrated using residual velocities. After the seismic event data is fully migrated, the effect of time stretching is removed by time unstretching the fully migrated seismic event data by a reverse operation to obtain a finally migrated seismic event data.
    Type: Grant
    Filed: December 18, 2000
    Date of Patent: October 15, 2002
    Assignee: PGS Americas, Inc.
    Inventors: Jiaxiang Ren, Steve Kelly, Ruben Martinez
  • Patent number: 6061301
    Abstract: A method and system for correcting seismic survey signals for separating and correcting for the effects of azimuthal anisotropy caused by the overburden, rather than the subsurface reflectivity, is disclosed. Following an initial estimate and normal moveout correction of the traces in a common midpoint gather, analytical traces are generated for coefficient series corresponding to zero-offset travel time response and to the azimuthal anisotropy, over the corrected gather. The quadrature-phase component of the azimuthal anisotropy coefficient series relative to the zero-offset travel time coefficient series indicates the effects of overburden azimuthal anisotropy, while the in-phase component indicates the effects of azimuthal anisotropy from subsurface reflective interfaces. Additional normal moveout correction to correct for the overburden azimuthal anisotropy may then be performed.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: May 9, 2000
    Assignee: Atlantic Richfield Company
    Inventor: Dennis Corrigan
  • Patent number: 5999488
    Abstract: An improved method for eliminating reflections from artificial model boundaries encountered in finite-difference acoustic wave propagation computations is based on applying two different boundary conditions at the artificial boundary. In this method one boundary condition generates reflections having the same polarity as the incident acoustic wave, and the other boundary condition generates reflections with opposite polarity. To apply the improved method simply compute both boundary conditions on a small narrow region adjacent the artificial boundary on a separate set of grids and average the two solutions.
    Type: Grant
    Filed: April 27, 1998
    Date of Patent: December 7, 1999
    Assignee: Phillips Petroleum Company
    Inventor: Brackin A. Smith
  • Patent number: 5978314
    Abstract: A method for determining a substantially optimal NMO velocity function for use in stacking a CMP gather of seismic data traces. The method begins with an initial estimate of the NMO velocity function for the CMP gather. This initial estimate is typically determined through conventional seismic velocity analysis. The method then picks a first velocity-traveltime pair falling on the initial estimate of the NMO velocity function and conducts a two-dimensional interpolative search of trial velocity-traveltime pairs in the neighborhood of the pick to find a substantially optimal velocity-traveltime pair. This substantially optimal velocity-traveltime pair is the trial velocity-traveltime pair having the highest stack response and is substituted for the pick in the NMO velocity function. The method then proceeds to find substantially optimal velocity-traveltime pairs to replace each of the other picks on the initial estimate of the NMO velocity function.
    Type: Grant
    Filed: March 21, 1997
    Date of Patent: November 2, 1999
    Assignee: Exxon Production Research Company
    Inventor: Long Don Pham
  • Patent number: 5808964
    Abstract: The object of the method according to the invention is to synthesize zero-offset seismic data from data acquired within the scope of three-dimensional (or possibly two-dimensional) multiple-offset seismic reflection prospecting operations in a subsurface environment. It mainly comprises selection of a distribution model of the velocities in the environment, seismic data prestack migration (stacking of the multiple-offset seismic events is achieved in the depth domain), and synthesis of zero-offset seismic data in the time domain by applying to the results obtained with this depth domain stacking a known modelling technique, for example that referred to as explosive reflector technique.
    Type: Grant
    Filed: June 6, 1996
    Date of Patent: September 15, 1998
    Assignee: Institut Francais du Petrole
    Inventors: Patrick Lailly, Bertrand Duquet, Andreas Ehinger
  • Patent number: 5724310
    Abstract: An array of output image points is distributed over a velocity model of a subsurface region of interest. A fan of rays is shot from each of a plurality of acoustic source points along the surface, the angular separation between the rays being equal to .pi./n, where n is the number of rays. A family of traveltime wavefronts is erected at selected time intervals, .DELTA.t, along the ray trajectories. The resulting wavefront map is superimposed over the array of output image points. Sub-arrays of output image points will lie within discrete traveltime cells, the widths of which are defined by the separation between adjacent rays paths and the heights are defined by the wavefront separation distance. Ray segments, wavefront segments and output image points are identified by a velocity layer index. A velocity interface that may cut across a traveltime cell, divides the cell into two parts, each having a different layer index.
    Type: Grant
    Filed: October 15, 1996
    Date of Patent: March 3, 1998
    Assignee: Western Atlas International, Inc.
    Inventors: Goran Milan Stankovic, Uwe Karsten Albertin
  • Patent number: 5663928
    Abstract: A method of analysing and processing seismic reflection data for the determination of a high resolution spatial hyperbolicity correction velocity field.The method is characterised in that:for the set of normal moveout-corrected gathers, the maximum values of the positive and negative residues of the NMO correction are determined: a time range analysis is determined located on either side of a time t.sub.0 and of which the width is equal to not more than twice the absolute value of the maximum residual moveout,a family of 2n+1 residual correction hyperbolas or parabolas are constructed, each having its apex centered on said time t.sub.0 and, at the value of the maximum offset, presenting a value of time that is equal to one of the 2n+1 equidistant time values predetermined on the analysis range, and including the value t.sub.0 and the extreme values of said analysis range,2n+1 sets of static corrections are determined for each of the offsets, defined by the time differences presented relative to said time t.
    Type: Grant
    Filed: June 18, 1996
    Date of Patent: September 2, 1997
    Assignee: Elf Aquitaine Production
    Inventors: Eric De Bazelaire, Jean-Pierre Dunand
  • Patent number: 5648937
    Abstract: A method and apparatus for adjusting the results of a seismic survey according to well log data obtained from wells within the survey region is disclosed. The disclosed method operates on one seismic horizon at a time, and first applies well log data, arranged by location of the wells in the survey region, to the seismic survey. Deviation values are calculated for each well location, as a signed difference between the actual depth data for the geological interface and a deduced horizon depth from the seismic survey. A difference function is evaluated for each survey point to be adjusted in the survey region (ranging from a single point to all survey points), preferably as a weighted average of the deviations at the wells, where the weighting is inversely related to the distance of the well from the survey point under adjustment.
    Type: Grant
    Filed: January 18, 1995
    Date of Patent: July 15, 1997
    Assignee: Atlantic Richfield Company
    Inventor: Bruce S. Campbell