Westerngeco L.l.p.

Johan O A Robertsson

Dirk-Jan Van Manen

Robert Montgomery Laws

David Fraser Halliday

Nicolas Goujon

Julian Edward Kragh

Ahmet Kemal Ozdemir

Everhard Johan Muyzert

Jon-Fredrik Hopperstad

Massimiliano Vassallo

Svein Arne Frivik

Lasse Amundsen

Ottar Kristiansen

Julian Edward (Ed) Kragh

Henk Keers

Aslaug Stroemmen Melboe

Morten Svendsen

Luren Yang

Tage Rosten

Ali Ozbek

Pascal Guillaume Edme

Oeyvind Teigen

Robin Fletcher

James Rickett

Philip A F Christie

Rohitashva Singh

Ali Özbek

Qinglin Liu

Christopher H Chapman

Remco Muijs

Roshitashva Singh

Ed Kragh

A technique includes receiving first data acquired by at least a particle motion gradient sensor or a rotation sensor of a streamer that is subject to vibration due to towing of the streamer; and receiving second data acquired by at least one particle motion sensor of the streamer and being indicative of particle motion and vibration noise. The technique includes processing the second data in a processor-based machine to, based at least in part on the first data, attenuate the vibration noise indicated by the second data to generate third data indicative of the particle motion.

Processing seismic data to attenuate vibration noise

A technique includes receiving data indicative of a wavefield in a processor-based system and processing the data on the processor-based system to generate a modeled wavefield. The processing includes varying boundary conditions of the modeled wavefield with respect to time to regulate coherent boundary reflections in the modeled wavefield.

Regulating coherent boundary reflections during generation of a modeled  wavefield

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.

Seismic data acquisition and source-side derivatives generation and application

To acquire near-zero offset survey data, a survey source and a first streamer attached to the survey source are provided, where the first streamer has at least one survey receiver. A second streamer separate from the survey source and the first streamer includes survey receivers. Near-zero offset data is measured using the at least one survey receiver of the first streamer.

Acquiring near-zero offset survey data

A technique facilitates collection and use of data on subterranean formations. The technique comprises obtaining gravity measurements through the use of seismic streamers. At least one streamer is provided such that each streamer has multiple sensors, e.g. accelerometers. The at least one streamer is towed with a tow vessel, and gravity data are accumulated via the multiple sensors during towing.

Gravity measurements using seismic streamers

A technique includes receiving first data indicative of a pressure measurement and measurements of components of a particle motion vector acquired by sensors disposed on at least one cable; and processing the first data to generate second data indicative of a constructed an in-line component of the particle motion vector. The technique includes processing the first and second data in a geophysical processing operation that relies on at least three components of the particle motion vector.

Processing multi-component seismic data

Implementations of various technologies for a method for generating a seismic image of a subsurface are described herein. Seismic data may be received from two sensors in a seismic survey. The seismic data below and equal to a predetermined frequency may be classified as low-frequency seismic data. The low-frequency seismic data may be re-sampled based on the predetermined frequency. A set of low-frequency Green's functions may be calculated using interferometry on the re-sampled low-frequency seismic data. High-frequency seismic data of the seismic data may be processed to create a set of high-frequency Green's functions at one or more source locations of the seismic survey. The set of high-frequency Green's functions may be merged with the set of low-frequency Green's functions to create a set of broad-band Green's functions. The seismic image may be generated using the set of broad-band Green's functions at the source locations.

Interferometric seismic data processing

A seismic streamer system for acquiring seismic data includes a plurality of first cable sections each employing a first sensor configuration therein, and at least one second cable section operatively connected to one or more of the first cable sections and employing a second sensor configuration therein. In various embodiments of the streamer system, one or more of the second cable sections are sparsely integrated into a streamer, a streamer array and/or a seismic spread. The first sensor configuration may, e.g., include a conventional hydrophone distribution, and the second sensor configuration may, e.g., include multicomponent sensors such as at least one of a particle velocity sensor, a pressure gradient sensor, an accelerometer and a combination thereof. The present invention is useful for attenuating noise in the measured seismic data as well as deghosting the data. A particular deghosting process includes decomposing the up- and down-going parts of the vertical component of particle velocity associated with the acoustic wave reflections from the strata.

Seismic streamer system and method

To perform noise attenuation for seismic surveying, a sensor assembly is deployed on a ground surface, where the sensor assembly has a seismic sensor to measure seismic waves propagated through a subterranean structure, and a divergence sensor comprising a pressure sensor to measure noise. First data is received from the seismic sensor, and second data is received from the divergence sensor. The first data and the second data are combined to attenuate noise in the first data.

Combining seismic data from sensors to attenuate noise

A seismic streamer system for acquiring seismic data includes a plurality of first cable sections each employing a first sensor configuration therein, and at least one second cable section operatively connected to one or more of the first cable sections and employing a second sensor configuration therein. In various embodiments of the streamer system, one or more of the second cable sections are sparsely integrated into a streamer, a streamer array, and/or a seismic spread. The first sensor configuration may, e.g., include a conventional hydrophone distribution, and the second sensor configuration may, e.g., include multicomponent sensors such as at least one of a particle velocity sensor, a pressure gradient sensor, an accelerometer, and a combination thereof. The present invention is useful for attenuating noise in the measured seismic data as well as deghosting the data. A particular deghosting process includes decomposing the up- and down-going parts of the vertical component of particle velocity associated with the acoustic wave reflections from the strata.

Acquiring near zero offset survey data

A technique includes obtaining first measurements acquired by sensors of a towed seismic streamer, which are indicative of an inclination of the streamer. Based at least in part on the measurements, a shape of the streamer while in tow is determined.

System and technique to obtain streamer depth and shape and applications thereof

A technique includes simulating seismic wave propagation based on an acoustic model and based on a result of the simulation, estimating an error between the result and another result obtained if the seismic wave propagation were simulated based on an elastic model. The technique includes based at least in part on the estimated error predicting the other result without performing the simulation based on the elastic model.

Correcting an acoustic simulation for elastic effects

A technique includes obtaining pressure data that was acquired by seismic sensors towed as part of a three-dimensional spread of streamers and obtaining particle motion data, which are indicative of particle motion at locations of the sensors. The technique includes estimating cross-line spectra of the pressure data based at least in part on the pressure data, and the technique includes deghosting the particle motion data based at least in part on the estimated cross-line spectra.

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Grantchester, United Kingdom

Johan O A Robertsson