Patents by Inventor Ahmet Kemal Ozdemir

Ahmet Kemal Ozdemir has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20110292762
    Abstract: A technique includes receiving seismic data acquired by seismic sensors; and processing the seismic data on a machine to deghost the data. The processing includes deghosting the seismic data using a first deghosting technique that relies on a ghost model; deghosting the seismic data using a second deghosting technique that is independent from any modeling of the ghost; and selectively combining the results of the deghosting using the first and second deghosting techniques.
    Type: Application
    Filed: November 24, 2010
    Publication date: December 1, 2011
    Inventors: Ahmet Kemal Ozdemir, Bent Andreas Kjellesvig, Philippe Bernard Albert Caprioli, Philip A. F. Christie, Julian Edward (Ed) Kragh
  • Publication number: 20110178714
    Abstract: A technique includes receiving seismic data indicative of measurements acquired by seismic sensors. The measurements are associated with a measurement noise. The technique includes estimating at least one characteristic of the measurement noise and deghosting the seismic data based at least in part on the estimated characteristic(s) of the measurement noise.
    Type: Application
    Filed: January 15, 2010
    Publication date: July 21, 2011
    Inventors: Ahmet Kemal Ozdemir, Philippe Caprioli, Ali Ozbek, Dirk-Jan Van Manen, Massimiliano Vassallo
  • Publication number: 20110103181
    Abstract: A technique includes distributing particle motion sensors along the length of a seismic streamer. Each particle motion sensor is eccentrically disposed at an associated angle about an axis of the seismic streamer with respect to a reference line that is common to the associated angles. The sensors are mounted to suppress torque noise in measurements that are acquired by the particle motion sensors. This mounting includes substantially varying the associated angles.
    Type: Application
    Filed: November 3, 2009
    Publication date: May 5, 2011
    Inventors: Ahmet Kemal Ozdemir, Oeyvind Teigen, Lars Borgen
  • Publication number: 20110103183
    Abstract: A technique includes receiving data indicative of non-uniformly spaced samples of particle motion wavefield acquired by particle motion sensors while in tow. The samples are spaced apart by an average spacing interval, which is not small enough to prevent vibration noise from being aliased into a signal cone for a first signal formed from samples of the particle motion wavefield having a uniform spacing at the average spacing interval. The technique includes processing the data to generate a second signal that is indicative of the particle motion wavefield and does not have aliased vibration noise in the signal cone.
    Type: Application
    Filed: November 3, 2009
    Publication date: May 5, 2011
    Inventors: Ahmet Kemal Ozdemir, Lars Borgen
  • Publication number: 20110002192
    Abstract: A technique includes representing actual measurements of a seismic wavefield as combinations of an upgoing component of the seismic wavefield and ghost operators. Interpolated and deghosted components of the seismic wavefield are jointly determined based at least in part on the actual measurements and the representation.
    Type: Application
    Filed: September 15, 2010
    Publication date: January 6, 2011
    Inventors: Ali Ozbek, Ahmet Kemal Ozdemir, Massimiliano Vassallo
  • Patent number: 7817495
    Abstract: A technique includes representing actual measurements of a seismic wavefield as combinations of an upgoing component of the seismic wavefield and ghost operators. Interpolated and deghosted components of the seismic wavefield are jointly determined based at least in part on the actual measurements and the representation.
    Type: Grant
    Filed: June 2, 2008
    Date of Patent: October 19, 2010
    Assignee: WesternGeco L.L.C.
    Inventors: Ali Ozbek, Ahmet Kemal Ozdemir, Massimiliano Vassallo
  • Publication number: 20100211323
    Abstract: There is provided a method of interpolating wave signals, particularly seismic signals acquired through a seismic survey, using the steps of obtaining time series of measured wave signals; and selecting iteratively basis functions to represent said measured signals with a basis function being fully defined by n parameters, wherein in each iteration one or more basis functions are combined with the selected basis functions such that the residual between the measured signals and a representation of the measured signal by the combined basis functions is minimized at the locations of the measurement at each iteration.
    Type: Application
    Filed: June 6, 2008
    Publication date: August 19, 2010
    Inventors: Ahmet Kemal Ozdemir, Ali Ozbek
  • Publication number: 20100211320
    Abstract: A technique to reconstruct a seismic wavefield includes receiving datasets, where each dataset is indicative of samples of one of a plurality of measurements of a seismic wavefield that are associated with a seismic survey. The technique includes modeling the plurality of measurements of a seismic wavefield as being generated by the application of at least one linear filter to the seismic wavefield. The technique includes processing the datasets based on the linear filter(s) and a generalized matching pursuit technique to generate data indicative of a spatially continuous representation of the seismic wavefield.
    Type: Application
    Filed: February 13, 2009
    Publication date: August 19, 2010
    Inventors: Massimiliano Vassallo, Ali Ozbek, Dirk-Jan Van Manen, Ahmet Kemal Ozdemir
  • Publication number: 20100211321
    Abstract: A technique includes receiving data, which are indicative of measurements acquired by seismic sensors of a seismic wavefield. The seismic wavefield is formed from a combination of an upgoing wavefield and a downgoing wavefield. The technique includes providing a statistical estimator, which relates the upgoing wavefield to a linear combination of the measurements and a reconstruction error. The technique includes determining the upgoing wavefield based on the statistical estimator. The determination includes substantially minimizing a variance of the reconstruction error.
    Type: Application
    Filed: February 13, 2009
    Publication date: August 19, 2010
    Inventors: Ahmet Kemal Ozdemir, Ali Ozbek, Massimiliano Vassallo, Dirk-Jan Van Manen
  • Publication number: 20100211322
    Abstract: A technique includes receiving seismic data acquired in a seismic survey. The survey has an associated undersampled direction, and the seismic data contains samples, which are indicative of a pressure wavefield and a directional derivative of the pressure wavefield that contains information related to vertical variations. The technique includes relating the samples to the pressure wavefield or to the directional derivative of the pressure wavefield using at least one linear filter and based on the relationship, constructing a substantially unaliased continuous representation of the pressure wavefield or the directional derivative of the pressure wavefield along the undersampled direction.
    Type: Application
    Filed: February 13, 2009
    Publication date: August 19, 2010
    Inventors: Massimiliano Vassallo, Dirk-Jan Manen, Ali Ozbek, Ahmet Kemal Ozdemir
  • Publication number: 20100202251
    Abstract: A technique includes receiving data indicative of a first measurement acquired by a rotation sensor on a seismic streamer and based on the first measurement, estimating a torque noise present in a measurement acquired by a second sensor on the streamer. The technique includes attenuating the torque noise based on the estimate.
    Type: Application
    Filed: February 11, 2009
    Publication date: August 12, 2010
    Inventors: Ahmet Kemal Ozdemir, Vidar Anders Husom, Nicolas Goujon, Oeyvind Teigen, Lars Borgen
  • 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
  • Patent number: 7676327
    Abstract: A technique for decomposing a recorded wave field represented in a set of multicomponent, marine seismic data centers around a computer-implemented method including: estimating the statistics of the noise terms in each one of a predetermined group of seismic measurements in a seismic data set acquired in a marine survey; modeling the physical propagation of a recorded wave field represented in the seismic data set from the estimated statistics; and estimating a directional component of the recorded wave field from the physical propagation model that minimizes error relative to the seismic measurements.
    Type: Grant
    Filed: April 26, 2007
    Date of Patent: March 9, 2010
    Assignee: WesternGeco L.L.C.
    Inventors: Ahmet Kemal Ozdemir, Ali Ozbek
  • Publication number: 20100039888
    Abstract: A computer-implemented method includes accessing a set of multicomponent marine noise data exhibiting a plurality of polarization vectors at each of a plurality of co-located pressure and particle motion data points on a marine seismic survey apparatus; and determining a set of perturbation noise data for the marine seismic survey apparatus from the polarization vectors. Computer readable program storage media are encoded with instructions that, when executed by a processor, perfume the computer-implemented method. One computing apparatus is programmed to perform the computer-implemented method.
    Type: Application
    Filed: August 17, 2008
    Publication date: February 18, 2010
    Inventors: Ahmet Kemal Ozdemir, Nicolas Goujon, Lars Borgen
  • Publication number: 20100002541
    Abstract: A technique includes modeling interpolated seismic measurements as a random process characterized by seismic measurements acquired at a set of sensor locations and an interpolation error. The technique includes determining the interpolated seismic measurements based at least in part on a minimization of the interpolation error.
    Type: Application
    Filed: July 5, 2008
    Publication date: January 7, 2010
    Inventors: Ahmet Kemal Ozdemir, Ali Ozbek, Massimiliano Vassallo
  • Publication number: 20090296523
    Abstract: A technique includes representing actual measurements of a seismic wavefield as combinations of an upgoing component of the seismic wavefield and ghost operators. Interpolated and deghosted components of the seismic wavefield are jointly determined based at least in part on the actual measurements and the representation.
    Type: Application
    Filed: June 2, 2008
    Publication date: December 3, 2009
    Inventors: ALI OZBEK, AHMET KEMAL OZDEMIR, MASSIMILIANO VASSALLO
  • Publication number: 20090161487
    Abstract: A technique includes determining a displacement of an acoustic sensor while in tow. Based on the determined displacement of the sensor, a measurement that is acquired by the sensor is compensated to remove noise from the measurement.
    Type: Application
    Filed: August 17, 2008
    Publication date: June 25, 2009
    Inventors: PER KJELLGREN, Bent Andreas Kjellesvig, Ahmet Kemal Ozdemir, Oeyvind Teigen, Lars Borgen
  • Publication number: 20090092003
    Abstract: A technique includes towing a particle motion sensor in connection with a seismic survey and controlling the survey to cause a notch in a frequency response of the particle motion sensor to substantially coincide with a frequency band at which aliased vibration noise appears in a seismic signal acquisition space of the particle motion sensor.
    Type: Application
    Filed: July 8, 2008
    Publication date: April 9, 2009
    Inventors: NICOLAS GOUJON, Johan O.A. Robertsson, Oeyvind Teigen, Ahmet Kemal Ozdemir
  • Publication number: 20090073028
    Abstract: System and method for detection and tracking of targets, which in a preferred embodiment is based on the use of fractional Fourier transformation of time-domain signals to compute projections of the auto and cross ambiguity functions along arbitrary line segments. The efficient computational algorithms of the preferred embodiment are used to detect the position and estimate the velocity of signals, such as those encountered by active or passive sensor systems. Various applications of the proposed algorithm in the analysis of time-frequency domain signals are also disclosed.
    Type: Application
    Filed: August 13, 2008
    Publication date: March 19, 2009
    Inventors: Orhan Arikan, Ahmet Kemal Ozdemir
  • Publication number: 20090056411
    Abstract: To calibrate an accelerometer, a seismic cable that carries the accelerometer is rotated. Data measured by the accelerometer as the seismic cable is rotated is received, and at least one calibration parameter according to the received data is computed. The at least one calibration parameter is for use in calibrating the accelerometer.
    Type: Application
    Filed: August 17, 2008
    Publication date: March 5, 2009
    Inventors: Nicolas Goujon, Ahmet Kemal Ozdemir, Bent Andreas Kjellesvig