Abstract: Streamer and method for deploying the streamer for seismic data acquisition related to a subsurface of a body of water. The method includes a step of releasing into the body of water, from a vessel, a body having a predetermined length together with plural detectors provided along the body; a step of towing the body and the plural detectors such that the plural detectors are submerged; and a step of configuring plural birds provided along the body, to float at a predetermined depth from a surface of the water such that a first portion of the body has a curved profile while being towed underwater.

Abstract: A method for deghosting seismic data collected with a seismic system, the seismic data being related to a subsurface of a body of water. The method includes receiving the seismic data recorded by detectors distributed along a variable-depth profile; calculating migrated (d1) and mirror-migrated (d2) gathers based on the seismic data, wherein the migrated and mirror-migrated gathers depend on a feature characterizing a configuration of the seismic system; applying a joint deconvolution model to the migrated and mirror-migrated gathers (d1, d2) to calculate a single deghosted gather (dg); and generating a final image of the subsurface based on the single deghosted gather (dg). The feature is not present in a gather after a step of stacking that is performed prior to generating the final image.

Abstract: A method for processing seismic data including contiguous-sweep records corresponding to rotated sweep segments includes attenuating harmonics and generating stacked traces, each stacked trace being a weighted sum of traces corresponding to same location in the subsurface, based on seismic data from different seismic receivers, following plural shots at plural locations.

Abstract: Computing device, computer instructions and method for simultaneously denoising and attenuating multiples in seismic data recorded with seismic receivers. The method includes receiving the seismic data, wherein the seismic data includes a pressure P component and a vertical Z component; separating the seismic data into up-going U wave-fields and down-going D wave-fields; calculating an up-down deconvolution R based on the up-going U and the down-going D wave-fields; generating a multiple model M based on the up-down deconvolution R; and adaptively subtracting the multiple model M from the pressure P component to obtain a corrected pressure Pfree component from which simultaneously the noise and the multiples were removed. A multiple is a wave-field that propagates from a source to a receiver and experiences more than one reflection.

Abstract: An electromagnetic measurement system and related methods are provided. The system includes an electromagnetic source located at a predetermined depth and configured to generate electromagnetic waves in surrounding formations, and a grid of electromagnetic detectors located on a surface of the rock formation and configured to detect the electromagnetic waves generated by the electromagnetic source and reflected by an underground hydrocarbons reservoir. The system also includes a data processing unit configured to process first data and second data related to the electromagnetic waves detected by the grid of electromagnetic detectors, to extract changes of the underground hydrocarbon reservoir, the first data and the second data each being acquired for up to one week, at least two months apart from one another. The electromagnetic source and the grid of electromagnetic detectors are not moved or removed between when the first data was acquired and when the second data was acquired.

Abstract: The invention relates to a method for acquiring seismic data at a plurality of positions spread out over a zone on the seabed which includes transmitting acoustic waves in the water layer above the zone by a plurality of sources, for each of the acquisition positions, dropping from the surface a seismic acquisition equipment, the equipment comprising a seismic acquisition unit and autonomous guiding equipment adapted to receive while descending acoustic signals from the sources and to control its trajectory according to the received acoustic signals so as to direct said equipment towards said position, performing the seismic acquisition, causing the acquisition equipments to move up to the surface, and retrieving the acquisition equipments on the surface.

Abstract: Computing device, computer instructions and method for deghosting seismic data related to a subsurface of a body of water. The method may include receiving input seismic data recorded by seismic receivers that located at different depths (zr), generating migration data (du) and mirror migration data (dd) from the input seismic data, deriving a ghost free model (m) based on simultaneously using the migration data (du) and mirror migration data (dd), generating primary (p) and ghost (g) datasets based on the ghost free model (m), simultaneously adaptively subtracting the primary (p) and ghost (g) datasets from the migration data (du) to provide adapted primary (p?1 and p?2) and adapted residual (r?1 and r?2) datasets and generating a final image (f) of the subsurface based on the adapted primary (p?1 and p?2) and the adapted residual (r?1 and r?2) datasets.

Abstract: Methods and systems for generating a stable reverse time demigration (RTDM) equation for predicting wave phenomena such as reflections, refractions and multiples are described. A coupling term is added to an RTDM equation and reflectivity associated with the coupling term is replaced with a pseudo-density function derived from a nonlinear equation. The resultant coupled and stabilized RTDM equation is then used to predict the desired wave phenomena based on the applied seismic image.

Abstract: Numerical simulations of elastic wave propagation algorithms are critical components for seismic imaging and inversion. Finite-difference schemes yield good efficiency but cannot ensure the accuracy of the high frequency component. Pseudo-spectral algorithms are accurate up to the Nyquist frequency, but its efficiency depends on the optimization of the fast Fourier transform (FFT) algorithm. The conventional FFT algorithms are optimized for signal processing, in which problems are generally one dimensional time series. For 3D wave propagation, FFT algorithms have the potential to be further optimized. Under current computer hardware architecture, a vectorization scheme for high dimensional FFTs is presented. Compared to conventional numerical scheme implementations, the systems and methods disclose herein has the best performance on the slowest or higher dimensions of data.

Abstract: A marine source sub-array and method for generating a pressure wave in a body of water. The marine source sub-array includes a float configured to float in the body of water; base plates connected to the float through cables; plural individual source elements connected to the base plates and configured to generate pressure waves underwater; and a coverage plate located between the plural individual source elements and the float. The coverage plate has a surface area larger than a surface area of the float.

Abstract: Control mechanisms, computer software and methods for driving vibrational source arrays underwater. An incoherent acquisition scheme drives individual source elements simultaneously and incoherently while a coherent acquisition scheme drives high-frequency individual source elements simultaneously and incoherently and low-frequency individual source elements simultaneously and coherently. Thus, denser coverage and an increased energy input is achieved for the source arrays.

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).

Abstract: A cleaning device for cleaning a marine streamer towed underwater and related methods are provided. The cleaning device includes a housing configured to be attached to the streamer, a motor mounted inside the housing, a propeller configured be rotated by the motor and to drive the housing along and relative to the streamer in a towing direction, and a controller configured to control the motor and the propeller.

Abstract: A method for detecting faults of individual wave sources in a marine source array includes acquiring near-field data using sensors, the sensors being located near the individual wave sources. The method further includes generating an index for each of the individual wave sources based on (A) the near-field data and (B) information on the geometry of the marine source array that enables localizing the individual wave sources and respective sensors relative to one another. The method also includes comparing the index for each of the individual wave sources with a corresponding reference index for determining whether a fault has occurred.

Abstract: A method for processing seismic data acquired using the same seismic survey setup over long periods of time includes acquiring sets of seismic data using the same seismic survey setup over multiple days, the sets being gathered as repeated seismic data. The method further includes estimating a time-variable wavelet corresponding to unwanted waves, and determining a propagation of the time-variable wavelet, which propagation is assumed to be constant in time, by solving an inverse problem using the repeated seismic data and the estimated time-variable wavelet. The method also includes extracting signal data by subtracting a convolution of the estimated time-variable wavelet and the propagation from the repeated seismic data.

Abstract: Methods and systems are presented for generating and performing a seismic data acquisition mission based on an a priori sea current model and a seismic data acquisition operation model and a shooting solution model based on the a priori sea current model. The individual models can be updated based on releasing sample buoys through the survey area both before and during mission execution.

Abstract: Systems and method described herein provide for obtaining information which can be used to create a seismic image of a portion of the earth surrounding a well. A device for obtaining information for creating a seismic image proximate a well includes at least one set of acoustic transducers mounted to an exterior surface of a well tubing and configured to transmit at least one acoustic signal, at least one set of hydrophones mounted to the exterior surface of the well tubing and configured to receive at least one reflected acoustic signal; and a cable configured to convey information to and from the at least one set of acoustic transducers and the at least one set of hydrophones.

Abstract: A method and a retrievable vertical geophone cable for collecting seismic data underground. The retrievable vertical geophone cable includes an envelope having a first end at which a connector mechanism is provided to close the envelope; plural geophones distributed inside the envelope at predetermined positions; and a first expansion mechanism attached to a geophone of the plural geophones and configured to expand the envelope when actuated with a first fluid under pressure.

Abstract: A method and a mechanized system for deploying plural geophones underground for collecting seismic data. The mechanized system includes a vehicle configured to travel above ground and having a storage area that stores the plural geophones; a digging mechanism attached to the vehicle and configured to dig a trench when in contact with the ground; and a damping mechanism attached to the vehicle and configured to hold a geophone behind the digging mechanism relative to a traveling direction (X)) of the vehicle.

Abstract: Method and retrievable vertical hydrophone cable for collecting seismic data underground. The retrievable vertical hydrophone cable includes an envelope having a first end at which a connector mechanism is provided to close the envelope; plural hydrophones distributed inside the envelope at predetermined positions; and a fluid provided inside the envelope and around the plural hydrophones. The envelope increases its volume when the fluid is pressurized through the connector mechanism.