Abstract: A real time deflector monitoring system related to a deflector used in a seismic survey system is provided. The system includes a bridle block configured to connect the deflector to a first rope. The system further includes sensors embedded in the bridle block and configured to measure strength and direction of a tension in at least one of (A) the first rope and/or (B) one of rig ropes connecting the deflector to the bridle block. The system also includes a motion detector configured to acquire information related to deflector's motion.
Type:
Grant
Filed:
December 2, 2013
Date of Patent:
January 5, 2016
Assignee:
CGG SERVICES SA
Inventors:
Hervé Richer De Forges, Frederic Simonnot
Abstract: Deflectors configured to be attached to cables towed behind a vessel for performing a marine survey and associated methods are provided. A deflector has a body including a wing portion and a knuckle portion. The wing portion has substantially flat wings extending away from a position where the body is attached to the cable. The knuckle portion is configured to attach the wing portion to the cable so that the wing portion remains able to rotate about three rectangular axes while being towed underwater.
Abstract: Methods and devices for seismic data processing deblend seismic data gathered using simultaneous source acquisition by applying two different deblending techniques. The second deblending technique is applied to residual data obtained after applying the first deblending technique. At least one of these first and second deblending techniques uses a signal-to-noise map.
Type:
Grant
Filed:
June 11, 2015
Date of Patent:
December 8, 2015
Assignee:
CGG SERVICES SA
Inventors:
Adel Khalil, Gordon Poole, Margherita Maraschini
Abstract: Cooperative attenuation methods are applied to data sets acquired by surveying a same underground formation which therefore include substantially the same primary signal and different individual noise. The data sets are converted in a wavelet basis by applying a high angular resolution complex wavelet transform. When corresponding coefficients of the data set representations in the wavelet basis differ more than predefined thresholds the coefficients are attenuated as corresponding to noise.
Abstract: Methods and systems for separating P-S wave field data are described. Slowness values for the PP mode and the PS mode are estimated and are, typically, unequal based on aliased and/or irregularly sampled data. A calculation, in the space-time domain, based on a matrix of equations, generates separated P-wave and S-wave data. The separated P-wave data and S-wave data are output for further imaging.
Abstract: An autonomous underwater vehicle (AUV) for recording seismic signals during a marine seismic survey. The AUV (200) includes a body (204) having a flush shape; a buoyancy system (202) located inside the body and configured to control a buoyancy of the AUV while traveling underwater; a processor (108) connected to the buoyancy system and configured to select one of plural phases for the buoyancy system at different times of the seismic survey, wherein the plural phases include a neutral buoyancy, a positive buoyancy and a negative buoyancy; and a seismic sensor (110) for recording seismic signals.
Type:
Application
Filed:
December 19, 2013
Publication date:
November 26, 2015
Applicant:
CGG Services SA
Inventors:
Thierry Brizard, Jonathan Grimsdale, Alice Herve, Ivan Torres Tamanaja
Abstract: System and method for monitoring a reservoir underwater. The system includes plural nodes, each having a seismic sensor for detecting seismic waves; a remote operated vehicle (ROV) configured to deploy or retrieve the plural nodes to seabed; and an autonomous underwater vehicle (AUV) configured to monitor and exchange data with the plural nodes. At least one node of the plural nodes has a head that houses the seismic sensor and the head is configured to burrow in the seabed, up to a predetermined depth, and the head remains in electrical contact through a connector with a base of the at least one node.
Abstract: Methods for determining a seismic wave's propagation velocity in water for monitor seismic data of a 4D data set analyze a relationship between seafloor time-shifts and source-receiver offsets. The time-shifts are differences of normal move out corrected seafloor source-receiver travel times for pairs of traces. Each pair includes a base trace extracted from base seismic data of the 4D data set and a monitor trace extracted from the monitor seismic data, the traces corresponding to the same seafloor bin and having the same source-receiver offset.
Abstract: Devices and methods for stabilizing a tailbuoy attached to a streamer towed during a marine survey are provided. The tailbuoy includes a floating body configured to be connected to the streamer, and a keel attached to the floating body. The keel is configured to stabilize a motion of the tailbuoy along a towing direction while in a working state, and to be switched between the working state in which the keel is partially submerged and a retracted state in which the keel is removed from water.
Abstract: A method for attenuating noise in seismic data signals is described wherein seismic signals are transmitted using a pseudo-random frequency sweep signal. Noise is then attenuated from the resulting, acquired seismic data on pre-phase subtraction basis, e.g., before correlating or de-convolving the acquired seismic data. In this way, repetitions associated with, for example, diversity stacking techniques can be avoided.
Abstract: Systems and methods are provided for de-noising seismic data recorded by seismic receivers. A first portion of the seismic data having a first signal-to-noise ratio (SNR) to is processed to generate a de-noising operator or function. The de-noising operator is applied to a second portion of seismic data having a second SNR to remove noise from the second portion of the seismic data, where the first SNR is greater than the second SNR.
Abstract: Method, apparatus and system for calibrating and synchronizing a seismic acoustic source array (50) by taking into account both a time- break signal (500) and a near-field signal (504). A time delay between the time-break signal and the near-field signal is used to calculate an offset for adjusting the shooting of the source elements of the source array.
Abstract: Source signature of a source array is measured using an autonomous underwater vehicle which is not physically connected to surface equipment and uses acoustic signals for communication and/or location. Such measurements may be performed while the source array is towed, the AUV then moving in tandem with the source array.
Abstract: A method for controlling impulsive sources during a geophysical survey includes receiving a set of predetermined shooting times for an impulsive source, receiving a detonation authorization for the impulsive source, and delaying a triggering of the impulsive source until a next available shooting time of the plurality of predetermined shooting times. A corresponding apparatus and system are also disclosed herein.
Type:
Application
Filed:
November 15, 2013
Publication date:
May 21, 2015
Applicant:
CGG Services SA
Inventors:
Jason Jurok, Tom Preusser, Olivier Winter, Peter Maxwell
Abstract: A system for controlling impulsive sources during a geophysical survey includes a triggering unit that interfaces to an impulsive source and provides an estimated current location for the impulsive source and a shot controller configured to transmit a detonation authorization to the triggering unit. The shot controller or the triggering unit may inhibit detonation of an impulsive source connected to the selected triggering unit if an estimated current location of the impulsive source is substantially different than an intended shot location. A corresponding apparatus and method are also disclosed herein.
Abstract: According to an embodiment, a method for analyzing microseismic events associated with hydraulic fracturing detects a new microseismic event and assigns it to a cluster of other events having similar characteristics. Cluster characteristic(s), e.g., average event(s), average source mechanisms, and/or average locations, are updated and used to characterize a future microseismic events.
Abstract: A method and a marine front-end gear for connecting a set of streamers to a towing vessel. The front-end gear includes ropes for connecting a first sub-set of streamers to the vessel; lead-ins for connecting a second sub-set of streamers to the vessel; and a back loop cable electrically connected between tails of first and second adjacent streamers. The first streamer belongs to the first sub-set of streamers and the second streamer belongs to the second sub-set of streamers, and streamers of the first sub-set are interspersed with streamers of the second sub-set.
Type:
Grant
Filed:
February 6, 2013
Date of Patent:
April 28, 2015
Assignee:
CGG Services SA
Inventors:
Christophe Guevel, Pierre Le Roux, Raphaël Macquin, Jean-Pierre Degez
Abstract: A seismic survey system for surveying a subsurface. The system includes a dipole seismic source buried in a well and configured to generate P-waves having a first radiation pattern and to generate S-waves having a second radiation pattern; plural seismic sensors distributed about the dipole seismic source and configured to record seismic signals corresponding to the P- and S-waves; and a controller connected to the dipole seismic source and configured to drive it. A longitudinal axis of the dipole seismic source is inclined with an inclination angle (?) relative to gravity.
Type:
Application
Filed:
April 7, 2014
Publication date:
April 23, 2015
Applicant:
CGG SERVICES SA
Inventors:
Julien COTTON, Eric FORGUES, Francois-Xavier GRESILLON
Abstract: A method for acquiring geophysical data includes connecting a power module comprising a data transfer port and a power transfer port to a geophysical data acquisition device to provide a geophysical sensing node and deploying the geophysical sensing node. While deployed, data is transferred from the geophysical data acquisition device to the power module via the data transfer port and power is transferred from the power module to the geophysical data acquisition device via the power transfer port. The method also includes retrieving the geophysical sensing node and replacing the power module with a newly charged power module to provide a newly charged geophysical sensing node, and deploying the newly charged geophysical sensing node. Corresponding systems are also disclosed herein.
Abstract: Seismic wave sources and related methods are provided. A seismic wave source includes a housing, plural pillars and an excitation system. The housing is split in two halves along a plane including a longitudinal axis of the housing. The plural pillars are made of piezoelectric elements and are positioned inside the housing to have one end in contact with a semi-cylindrical middle portion of one half of the housing and another end in contact with a semi-cylindrical middle portion of the other half of the housing. The excitation system connected by wires to the plural pillars and is configured to provide electrical signals to the piezoelectric elements. Upon receiving the electrical signals from the excitation system, the pillars generate forces on the housing thereby generating seismic waves.