Westerngeco L.l.p.

Schlumberger Technology Corporation

Reflection Marine Norge As

Other

Schlumberger Canada Limited

David Fraser Halliday

Robert Montgomery Laws

Dirk-Jan Van Manen

Johan O A Robertsson

Julian Edward Kragh

Jon-Fredrik Hopperstad

Pascal Guillaume Edme

Andrew Curtis

Ali Ozbek

Everhard Johan Muyzert

Massimiliano Vassallo

Martin N Howlid

Everhard Johan Muijzert

Nihed El Allouche

Pieter Leonard Vermeer

David Neser

Filippo Broggini

Jon-Fedrik Hopperstad

Johan Robertsson

Robert Hughes Jones

Marine seismic surveys, including ocean bottom surveys, utilizing marine vibrator arrays that are capable of being driven in anti-phase to produce a directional source gradient. Marine seismic surveys may include activating the vibrator array to emit a plurality of radiation patterns with at least a first radiation pattern that has a first notch at a take-off angle that is not dose to vertical. Some marine seismic surveys included emitting directive wavefields from two or more simultaneous seismic source arrays, where the two or more seismic source arrays have a phase that changes from shot-to-shot to allow simultaneous source separation of the directive wavefields.

Marine vibrator directive source survey

A method for seismic imaging includes receiving a multi-shot seismic data set that was collected using one or more streamers having recorders configured to detect seismic waves that propagate through a subterranean domain. The method also includes partitioning the multi-shot seismic data set into windows including a source dimension. The method also includes defining one or more first basis functions that describe the windows of the multi-shot seismic data set. The method also includes generating a model that describes a decomposition of the multi-shot seismic data set using the one or more first basis functions. The method also includes defining one or more second basis functions that describe a selected output data. The method also includes combining the one or more second basis functions with the model to produce a result for a source side wavefield and a receiver side wavefield.

Reconstruction of multi-shot, multi-channel seismic wavefields

Marine seismic data can be processed to remove or reduce two or more source side acquisition effects jointly when 1) the effects are placed in the same data domain as the received data and 2) the effects are described using the same basis functions which may signify representing the received data and the effects in the same chosen transform domain. The data effects may include source signature removal, source radiation pattern removal, residual shot noise suppression and data regularization, multi-channel reconstruction or regularization, prediction of sea surface multiples, separation of simultaneous sources etc. The joint processing can use iterative or non-iterative inversion technique, where the iterative inversion technique may be a matching pursuit technique.

Removal of acquisition effects from marine seismic data

Marine seismic surveys, including ocean bottom surveys, utilizing marine vibrator arrays that are capable of being driven in anti-phase to produce a directional source gradient. Marine seismic surveys may include activating the vibrator array to emit a plurality of radiation patterns with at least a first radiation pattern that has a first notch at a take-off angle that is not close to vertical. Some marine seismic surveys includes emitting directive wavefields from two or more simultaneous seismic source arrays, where the two or more seismic source arrays have a phase that changes from shot-to-shot to allow simultaneous source separation of the directive wavefields.

A method for processing seismic data may include receiving, via a processor, the seismic data acquired via a seismic survey. The seismic survey may include seismic sources that emit seismic wavefields at different locations. Each of the seismic sources may change a directivity pattern of a respective seismic wavefield based on a respective location of the respective seismic source. The seismic survey may also include seismic receivers that may receive the seismic data. The method may also include generating one or more basis functions that correspond to measurements of the seismic data, modelling a signal component of the seismic data as a sum of the one or more basis functions, and storing the signal component in a storage component. The signal component may be used to acquire an image of a subsurface region of the earth for identifying a feature in the subsurface region of the earth.

Systems and methods for attenuating noise in seismic data and reconstructing wavefields based on the seismic data

Methods of acquiring and processing seismic data using derivative sensors, such as strain sensors, that facilitate ground roll noise attenuation with seismic interferometry are disclosed. The methods use both seismic data and their spatial derivatives in computing ground-roll noises which are removed from processed seismic data.

Seismic interferometry for grand roll and noise attenuation

Acquiring seismic data using time-distributed sources and converting the acquired data into impulsive data using a multiple-frequency approach. The methods are performed in frequency-source location domain, frequency-wavenumber domain, or frequency-slowness domain. The methods are applicable to single source acquisition or simultaneous source acquisition.

Reconstructing impulsive source seismic data from time distributed firing airgun array data

A technique for reconstructing a seismic wavefield includes receiving data over one or more channels of a plurality of channels from a plurality of stations. The data is recorded by a plurality of seismic receivers and represent measurements of properties of the seismic wavefield. Each station includes a region in space including one or more seismic receivers. Each channel either measures a property of the seismic wavefield or a property of the seismic wavefield after the seismic wavefield has undergone a known transformation. At least one channel is derived as a function of one or more other channels. The technique includes using a processor based machine to process the data to model the seismic wavefield as a sum of basis functions; apply to the basis functions at least one forward transformation that describes the measurements received over the channel(s); and determine optimum basis functions based at least in part on the measurements.

Wavefield reconstruction

A technique includes towing at least one seismic source in connection with a survey of a structure; and operating the seismic source(s) to fire shots, where each shot is associated with a frequency sweep. The technique includes varying phases of the frequency sweeps from shot to shot according to a predetermined phase sequence to allow noise in an energy sensed by seismic sensors to be attenuated.

Seismic data apparition from phase shifted sources

Seismic surveying techniques are described in which seismic receivers in a seismic array are used as seismic sources. These receiver-sources may be used to determine the near-surface structures of the Earth, geometric properties of the survey array, receiver locations and operations of the survey array. The receiver-sources may be driven by drive sequences to produce amplified receiver-source signals, plane waves, surface waves converging towards a point inside the seismic array, surface waves sweeping through the seismic array and/or the like. The receiver-sources may comprise geophones, hydrophones, accelerometers and/or the like. A driver may be used to drive the receiver-sources and the driver may be controlled by a processor. By encoding drive sequences, seismic data generated by the receiver-sources may be separated from seismic data generated by another seismic source in the seismic array. Similarly, seismic data can be separated by controlling the frequency of seismic signals produced by the receiver-sources.

Seismic receivers as seismic sources

Marine seismic vibrators in a marine seismic vibrator array for use in a seismic survey are activated to produce a source gradient wavefield to survey a target structure. The seismic survey may comprise a marine seismic survey conducted in a body of water.

Wavefield generation using a seismic vibrator array

Methods and apparatuses for land seismic survey are provided. The methods and apparatuses utilize spatial derivatives of a seismic wavefield to interpolate, regularize or extrapolate seismic data. The methods and apparatuses may considerably reduce land seismic field efforts and/or compensate data gaps.

Methods and systems for land seismic surveying

Seismic acquisition using phase-shifted sweeps

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

Methods and systems are disclosed to enhance surveying techniques. In one embodiment, a virtual response is estimated that corresponds to energy propagated within a subsurface region between a virtual source and a virtual source estimation receiver, wherein the subsurface region corresponds to a survey zone including: a plurality of receivers deployed within the survey zone, a first subzone having at least one actual source, a second subzone within the first subzone; the virtual source is a first receiver disposed in the second subzone; and the virtual source estimation receiver is a second receiver.

Growing community of inventors

Cambridge, United Kingdom

David Fraser Halliday