Entries |
Document | Title | Date |
20080219094 | Systems and Methods for Seismic Data Acquisition Employing Asynchronous, Decoupled Data Sampling and Transmission - Systems and methods for asynchronously acquiring seismic data are described, one system comprising one or more seismic sources, a plurality of sensor modules each comprising a seismic sensor, an A/D converter for generating digitized seismic data, a digital signal processor (DSP), and a sensor module clock; a seismic data recording station; and a seismic data transmission sub-system comprising a high precision clock, the sub-system allowing transmission of at least some of the digitized seismic data to the recording station, wherein each sensor module is configured to periodically receive from the sub-system an amount of the drift of its clock relative to the high precision clock. This abstract is provided to comply with rules requiring an abstract to ascertain the subject matter of the disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. | 09-11-2008 |
20080239870 | Underwater Detection Device - In an under water detection for detecting the phase difference of an echo by two reception beams according to a split beam method, the difference Δθ between the phase difference of an echo detected by first and second reception beams formed in some direction and the phase difference of the echo detected by first and second reception beams which is formed in a direction rotated from the former direction concerned by a predetermined angle is detected by a phase detector. A reliability judging unit judges whether the difference Δθ detected by the phase detector is within a predetermined range or not. If the difference Δθ is within the predetermined range, an echo is displayed on a display unit. If the difference Δθ is not within the predetermined range, the echo is displayed with a specific color tone or the echo is not displayed. | 10-02-2008 |
20080253226 | System and method for marine seismic surveying - A system for marine seismic surveying comprises at least one marine seismic streamer; at least one pressure sensor mounted in the at least one marine seismic streamer; at least one particle motion sensor mounted in the at least one marine seismic streamer and collocated with the at least one pressure sensor, wherein the at least one particle motion sensor has a resonance frequency above 20 Hz; and computer means for combining pressure data from the at least one pressure sensor and particle motion data from the at least one particle motion sensor for further processing. | 10-16-2008 |
20080253227 | Method for prediction of surface related multiples from marine towed dual sensor seismic streamer data - Particle motion sensor signals and the pressure sensor signals data from a towed marine seismic streamer are combined to generate an up-going pressure wavefield component and a down-going particle motion wavefield component. The down-going particle motion wavefield component is extrapolated from the receiver position depth level to the source position depth level. The up-going pressure wavefield component is multiplied by the extrapolated down-going particle motion wavefield component, generating a first product. Then, n | 10-16-2008 |
20090016158 | Seismic exploration process enabling the suppression of ghosts due to reflections at the water surface, and process for processing seismic data in order to suppress these ghosts - The invention relates to a process for marine seismic exploration at least two different depths by means of streamers, each including a set of hydrophones, the acquisition of data at the different depths being performed in a single exploration region, and in which the position of the streamers and the hydrophones when acquiring seismic data at a first depth is independent of the position of the streamers and hydrophones when acquiring seismic data at a second depth. | 01-15-2009 |
20090022009 | System and Technique to Estimate Physical Propagation Parameters Associated with a Seismic Survey - A technique includes estimating propagation parameters that are associated with a towed seismic survey based at least in part on seismic signal measurements and noise measurements. | 01-22-2009 |
20090034365 | Determining Seawater Conductivity for the Compensation of Electromagnetics-Based Survey Data - A technique includes obtaining seismic data, which was acquired during a seismic survey in seawater. The technique includes based on the seismic data, determining a conductivity of the seawater and processing data obtained from an electromagnetics-based survey based on the determined conductivity. | 02-05-2009 |
20090046536 | Method for noise suppression in seismic signals using spatial transforms - A method for identifying a position of a source of noise in a marine seismic record includes defining, for at least one shot record, a set of possible noise source positions. A difference between travel time of noise from each possible noise source position to each of a plurality receiver position for the at least one shot record is determined. Signals from at least a subset of the receiver positions are time-aligned with respect to the difference between travel times for each possible noise source position. The time-aligned signals are then stacked. The noise source position is determined from the stacked, time-aligned signals. This result can then be used to construct a model of the noise at the receiver position. | 02-19-2009 |
20090073804 | USING SOURCE ELEVATION MEASUREMENTS TO REMOVE SEA PERTURBATIONS - A method for correcting marine seismic data is described in which a measured surface elevation relative to a reference surface of an array of source units is used to compensate for variations in the height and/or shape of a sea surface. Various embodiments correct for the elevation of the array as a whole, differences in the elevation of source units within the array, and scattering from the sea surface which arises due to the sea surface not being flat. | 03-19-2009 |
20090122642 | Bottom-sediment classification device and method - A device and method for determining bottom sediment is provided. The method includes transmitting a pulse of a pulse width corresponding to a water-bottom depth, extracting a series of amplitude data of water-bottom echo signals from predetermined signals among the water-bottom echo signals received by the transducer at a predetermined time interval, normalizing the extracted series of amplitude data after TVG-processed, calculating two or more feature quantities based on the normalized series of amplitude data in each of segments of the normalized series of amplitude data, and a value corresponding to the water-bottom depth, and generating bottom-sediment classification information indicating the bottom sediment based on the two or more feature quantities. | 05-14-2009 |
20090135669 | Diagonal gather trace interpolation - Diagonal gather trace interpolation systems and methods are disclosed. In some embodiments, the method includes obtaining seismic traces from a marine seismic survey performed using typically two seismic sources fired in a flip-flop pattern. The seismic traces are processed in common field file trace groups from each cable by performing trace interpolation in opposing diagonal directions. Among other things, diagonal trace interpolation may improve azimuthal regularization. In any event, the disclosed interpolation methods maintain spatial bandwidth increased spatial resolution with increased inline and crossline sampling components. Diagonal gather trace interpolation exploits reduced input trace separation to provide improved stability and detection of a greater range of formation dip angles. After interpolation and regularization, the seismic traces may be imaged and interpreted for improved seismic exploration and monitoring. | 05-28-2009 |
20090147620 | Method for processing marine towed streamer seismic data from regular multi-azimuth surveys - Marine towed streamer seismic data are combined from a first survey and a second survey, wherein the first survey and the second survey are shot with a bin size of L×L and the second survey is shot with a shooting direction rotated 90° relative to the shooting direction of the first survey. The combined seismic data from the first and second surveys are binned on a bin grid with a bin size of | 06-11-2009 |
20090154289 | Systems and Methods for Seismic Data Acquisition Employing Clock Source Selection in Seismic Nodes - Systems and methods for acquiring seismic data are described, one system comprising one or more seismic sources, a plurality of sensor modules each comprising a seismic sensor configured to sample analog seismic data, each module comprising a comparing unit comprising software; wherein the software in each module tests clock quality by running a sigma-delta modulator from two different clock sources in the node and compares a noise-floor of the modulator when using the different clocks. | 06-18-2009 |
20090161486 | Method for regularizing offset distribution in towed seismic streamer data - Seismic data from towed marine streamers are sorted into two-dimensional common midpoint gathers of traces. The gathered traces are ordered by offset. The offset distribution of the ordered traces is regularized. The source and receiver coordinates of the regularized traces are adjusted to reflect the regularizing. | 06-25-2009 |
20090245020 | METHOD FOR DETERMINATION OF DIFFERENTIAL TRANSFER FUNCTION BETWEEN TWO CLOSELY SPACED HYDROPHONES - Methods and apparatus for determining an accurate differential transfer function (DTF) between two closely spaced hydrophones in a dual-hydrophone configuration such that the wavefield may be properly separated into up- and down-going components are provided. The methods disclosed herein are based on the premise that the cross-correlation at a lag of zero between up- and down-going wavefields should be at a minimum for perfectly matched hydrophones. Thus, any suitable global optimization technique may be utilized to determine an accurate DTF where the zero-lag cross-correlation between up- and down-going energy is at a minimum after multiplying a particular hydrophone spectrum of the pair (depending on how the DTF was defined) with a possible DTF suggested by the global optimization technique. | 10-01-2009 |
20090245021 | RECONSTRUCTING LOW FREQUENCY DATA RECORDINGS USING A SPREAD OF SHALLOW AND DEEP STREAMERS - A technique includes obtaining first data indicative of seismic measurements acquired by seismic sensors of a first set of towed streamers and obtaining second data indicative of seismic measurements acquired by seismic sensors of a second set of towed streamers. The second set of towed streamers is towed at a deeper depth than the first set of towed streamers. The technique includes interpolating seismic measurements based on the first and second data. The interpolation includes assigning more weight to the second data than to the first data for lower frequencies of the interpolated seismic measurements. | 10-01-2009 |
20090274005 | METHOD FOR MONITORING A MULTI-LAYERED SYSTEM - A method for monitoring a multi-layered system below a surface comprising a slow layer and a fast layer; the method comprising: transmitting one or more seismic waves from one or more seismic sources through the multi-layered system; receiving signals emanating from the multi-layered system in response to the one or more seismic waves with one or more receivers located a distance from the one or more seismic sources; identifying one or more critically refracted compressional (CRC) waves amongst the signals; and inferring information about a change in the slow layer based on the one or more CRC waves; wherein the CRC wave is a refracted wave which has traveled along an interface between the fast layer and an adjacent layer. | 11-05-2009 |
20090279386 | METHOD FOR DETERMINING ADEQUACY OF SEISMIC DATA COVERAGE OF A SUBSURFACE AREA BEING SURVEYED - A method for assessing data coverage in a three dimensional marine seismic survey includes determining at least one Fresnel zone for at least one of a plurality of seismic data traces. A contribution is determined for each of the seismic data traces to each one of a set of bins in a defined pattern. Each contribution is based on the Fresnel zone associated with each seismic data trace. The contributions from all seismic data traces contributing to each bin are summed. The summed contribution for each bin are stored or displayed and the summed contributions in each bin are compared to a selected threshold to determine coverage. | 11-12-2009 |
20090279387 | Marine passive seismic method for direct hydrocarbon detection - A method for detection of hydrocarbon bearing formations below the bottom of a body of water from seismic signals includes moving a plurality of spatially distributed seismic sensors in a body of water and detecting seismic signals including response to any seismic energy having frequencies down to proximate zero. The method includes stacking the acquired seismic signals from the plurality of the sensors in both longitudinal and transverse directions with respect to motion of the sensors in the body water. The stacked signals are analyzed for presence of passive seismic energy indicative of hydrocarbon bearing formations below the bottom of the body of water. | 11-12-2009 |
20090279388 | METHOD FOR DETERMINING ADEQUACY OF SEISMIC DATA COVERAGE OF A SUBSURFACE AREA BEING SURVEYED AND ITS APPLICATION TO SELECTING SENSOR ARRAY GEOMETRY - A method for marine seismic surveying includes towing a seismic sensors in a plurality of streamers in the water, actuating a seismic energy source in the water at selected times and detecting seismic signals at the sensors resulting from the actuation of the source. A data trace is created for each of the detected signals. At least one Fresnel zone is determined for at least some of the seismic data traces. A contribution of each of the traces to each one of a plurality of bins defined in a predetermined pattern is computed, based on the Fresnel zone associated with each trace. Based on the computed contributions, a maximum lateral distance between corresponding seismic sensors is determined that will result in a contribution sum above a selected threshold. | 11-12-2009 |
20090290448 | System and Technique to Determine High Order Derivatives from Seismic Sensor Data - A technique includes obtaining multi-component seismic data acquired by two or more seismic sensors while in tow. The multi-component seismic data is indicative of a pressure wavefield and particle motion. The technique includes based on the data, determining at least one high order (i.e., second order or higher) spatial derivative of the pressure wavefield. | 11-26-2009 |
20090310439 | METHOD TO DETERMINE THE DEVIATION OF SEISMIC EQUIPMENT FROM A PLANNED CURVED PATH - A group of techniques can be used to determine if components of a seismic spread have deviated from a planned path during a coil or other curved and substantially circular acquisition pattern. In one aspect, and in general, the presently disclosed techniques include a computer-readable program storage medium for determining the deviation of spread array element from a planned curved path during a towed-array marine seismic survey. The method comprises: determining a nominal position of the spread array element at a given point in the planned curved path; determining the actual position of the spread array element; and performing an error analysis predicated on the nominal and actual positions. | 12-17-2009 |
20090310440 | FILTERING AND PRESENTATION OF HEADING OBSERVATIONS FOR COIL SHOOTING - The presently disclosed technique includes a method that compensates for constantly changing headings as occur during coil shooting acquisition. In one aspect, the presently disclosed techniques include a computer-readable program storage medium comprising: accessing a set of heading data for a seismic spread acquired while traversing a curved path; and normalizing the accessed heading data to a dynamic frame of reference defined relative to the seismic spread. | 12-17-2009 |
20100008184 | Method for aquiring and processing marine seismic data to extract and constructively use the up-going and down-going wave-fields emitted by the source(s) - A method for acquisition and processing of marine seismic signals to extract up-going and down- going wave-fields from a seismic energy source includes deploying at least two marine seismic energy sources at different depths in a body of water. These seismic energy sources are actuated with known time delays that are varied from shot record to shot record. Seismic signals from sources deployed at different depths are recorded simultaneously. Seismic energy corresponding to each of the sources is extracted from the recorded seismic signals. Up-going and down-going wave-fields are extracted from the sources deployed at different depths using the extracted seismic energy therefrom. A method includes the separated up-going and down-going wave-fields are propagated to a water surface or a common reference, the up-going or the down-going wave-field is 180 degree phase shifted, and the signals from these modified up-going and down-going wave-fields are summed. | 01-14-2010 |
20100014382 | MEASURING FAR FIELD SIGNATURE OF A SEISMIC SOURCE - To estimate a far-field signature of a seismic source having plural source elements, seismic receivers are provided to receive signals from the seismic source elements of the seismic source. Seismic receivers are dynamically associated with different seismic source elements over time, and the far-field signature of the seismic source is computed according to the measurement data taken by the seismic receivers. | 01-21-2010 |
20100027375 | Method of summing dual-sensor towed streamer signals using seismic reflection velocities - A merged particle velocity signal is generated by merging a recorded vertical particle velocity signal, scaled in an upper frequency range using a time-dependent arrival angle as determined by velocity analysis, with a simulated particle velocity signal, calculated in a lower frequency range from a recorded pressure signal using a time-varying filter based on the time-dependent arrival time. Combined pressure and vertical particle velocity signals are generated by combining the recorded pressure and merged velocity signals. | 02-04-2010 |
20100097885 | REMOVING SEISMIC INTERFERENCE USING SIMULTANEOUS OR NEAR SIMULTANEOUS SOURCE SEPARATION - A technique includes providing seismic data that is indicative of energy that is sensed in response to a first operation of at least one seismic source in a first seismic survey and a second operation of at least one seismic source in a second seismic survey. The technique includes processing the seismic data to determine a timing of the second operation relative to the first operation, and the technique includes based at least in part of the determined timing, processing the seismic data to generate a dataset, which is indicative of the sensed energy that is attributable to the first operation and is not attributable to the second operation. | 04-22-2010 |
20100103772 | Marine Seismic Acquisition - A method of conducting multiple source, multiple signal seismic surveys in a marine environment are provided. | 04-29-2010 |
20100110830 | METHOD OF DETERMINING PROPERTIES OF THE EARTH - There is provided a method of direct waveform inversion of turning waves ( | 05-06-2010 |
20100118646 | Seismic vibrator array and method for using - A method for generating seismic energy for subsurface surveying includes operating a first seismic vibrator and operating at least a second seismic vibrator substantially contemporaneously with the operating the first seismic vibrator. A driver signal to each of the first and the at least a second seismic vibrators that are substantially uncorrelated with each other. | 05-13-2010 |
20100135113 | Method for determining signal quality in dual sensor seismic streamer signals - A method for determining quality of signals acquired using marine seismic streamers having pressure responsive sensors and motion responsive sensors includes cross ghosting pressure responsive seismic signals and contemporaneously acquired motion responsive seismic signals. First filters are determined that cause the cross ghosted pressure responsive signals to substantially match the cross ghosted motion responsive signals. Second filters are determined that cause the cross ghosted motion responsive signals to substantially match the cross ghosted pressure responsive signals. The first and second filters are convolved and the convolution is used to determine signal quality. | 06-03-2010 |
20100142318 | SIMULATING UP-GOING PRESSURE WAVEFIELD - Various methods for simulating up-going pressure wavefield data. In one implementation, a processing apparatus may receive pressure data from pressure sensors that may be installed on a first and second streamer of an over/under streamer pair. The processing apparatus may also receive velocity data from velocity sensors that may be installed on the second streamer of the over/under streamer pair. Using the pressure and velocity data obtained from the sensors installed on each streamer, the processing apparatus may simulate the pressure and velocity data that would have been obtained by a streamer in a calm sea at a depth equal to the vertical distance between the first and second streamers. The simulated pressure and velocity data may then be combined to estimate the up-going pressure wavefield data. | 06-10-2010 |
20100172208 | SYSTEM AND TECHNIQUE FOR LOCAL IN-SEA PROCESSING OF PARTICLE MOTION DATA - A system includes a seismic streamer, which includes particle motion sensors and processors. Each processor is associated with a different one of the particle motion sensors and is adapted to process data acquired by the associated particle motion sensor to compensate the data for a characteristic of the sensor. | 07-08-2010 |
20100182873 | Method for wavefield separation for dual-sensor data using kirchhoff-type datuming and migration - A first weighted integral operator is applied to dual-sensor data to extrapolate the dual-sensor data to a first position above an acquisition surface, generating extrapolated data. A second weighted integral operator is applied to the extrapolated data to extrapolate the extrapolated data to a second position, generating wavefield separated data. One of the integral operators is applied to a scaled combination of the dual sensor data. | 07-22-2010 |
20100202250 | IMAGING WITH VECTOR MEASUREMENTS - A technique includes receiving seismic data, which are indicative of pressure measurements and pressure gradient measurements acquired in a seismic survey of at least one subterranean formation. The technique includes modeling an image of the subterranean formation(s) as a function of the pressure measurements and the pressure gradient measurements. The technique includes determining the image based on the modeling. | 08-12-2010 |
20100226205 | Method for marine electrical survey of oil-and-gas deposits - A method for survey of hydrocarbon deposits in a researched profile of sea-bottom comprises providing a generator generating pulse electric current with a generator frequency in a towable generator line exciting electric field signals measured by sea-bottom stations synchronized with the generator, forming space-domain data arrays for the generator frequency and for higher odd harmonics frequencies nearest thereto, forming time-domain data arrays for selected offsets, inversion of the time-domain and space-domain data, and determining a bottom strata resistivity and polarization characteristics for the researched profile, based the inversion's results. The inversion preferably encompasses synchronizing and adjusting the generator line and electric field signals, dividing them into a frequency branch, including a fast Fourier transform and a robust summation producing the space-domain arrays, and a time-domain branch, including a robust summation producing the time-domain arrays. Embodiments include transient field analysis with spatial derivatives, special towing configurations, generator line types choices, etc. | 09-09-2010 |
20100302901 | SYSTEM AND METHOD OF USING AUTONOMOUS UNDERWATER VEHICLE TO FACILITATE SEISMIC DATA ACQUISITION - A technique facilitates the use of seismic data. The technique utilizes an autonomous underwater vehicle to obtain data on water column characteristics in a seismic survey area. The data can be used to adjust aspects of the seismic survey data and/or the seismic survey technique. | 12-02-2010 |
20100302902 | DIGITAL AIR GUN - A marine air gun generates an acoustic signal in water, for example, during a marine seismic survey. The marine air gun includes digital electronic circuitry. The digital electronic circuitry may control an actuator of the marine air gun, digitize and store data from sensors located on or near the marine air gun, send and/or receive digital communications, store and/or output electrical energy, and/or perform other functions. A marine seismic source system that includes multiple air gun clusters may have a separate digital communication link between a command center and each air gun cluster. Each communication link may provide power and digital communication between the command center and one of the air gun clusters. | 12-02-2010 |
20100322028 | Control system for marine vibrators and seismic acquisition system using such control system - A method for controlling output of a marine seismic vibrator includes operating the vibrator using a predetermined driver signal. A vibrator output signal is measured at at least two different places on the vibrator. The at least two measured vibrator output signals are used to determine a corrected driver signal, wherein the corrected driver signal results in fewer harmonics of fundamental frequencies in the vibrator output. The vibrator is operated using the corrected driver signal. | 12-23-2010 |
20110032795 | Method for Reducing Marine Source Volume While Maintaining Image Quality - A technique facilitates the acquisition of seismic data at a substantially reduced source volume. The methodology generally comprises conducting a seismic survey with seismic sources that have a reduced source volume to collect seismic data. The low frequency data which is lost due to the reduced source volume is replaced with data acquired from a complementary method, such as a receiver-side acquisition method. The two sets of data are combined to provide a comprehensive seismic survey image without requiring conventional seismic source volume. | 02-10-2011 |
20110032796 | System and method for producing an acoustic pulse using live steam - An improved system and method for seismic exploration using live steam involves creating a cavity of live steam in a body of water, the cavity of live steam imploding due to the water cooling the live steam thereby producing an acoustic pulse, receiving reflections of the acoustic pulse at one or more receivers, and processing the reflections of the acoustic pulse. The cavity of live steam can be created by controlling release valves to introduce live steam into the body of water or by introducing hydrogen and at least one of oxygen or air into the water to create a bubble and then igniting the bubble. | 02-10-2011 |
20110038225 | Method for generating spread spectrum driver signals for a seismic vibrator array using multiple biphase modulation operations in each driver signal chip - A method for generating seismic energy for subsurface surveying include operating a first seismic vibrator above an area of the subsurface to be surveyed and operating at least a second seismic vibrator above the area substantially contemporaneously with the operating the first seismic vibrator. The first and the second vibrators each have a different selected frequency response. The first and second vibrators each is operated by a same direct sequence spread spectrum signal, wherein a different number of modulation operations for each logical value in the direct sequence spread spectrum signal is selected for each vibrator. | 02-17-2011 |
20110038226 | Remote seismic surveying systems and methods - Remote seismic surveying systems and methods are disclosed. At least some embodiments illuminate a water or ground surface with a beam from a coherent electromagnetic wave source. Reflected electromagnetic energy is focused onto an image plane where it combines with a reference beam to form an interference pattern. Electronics track the intensity versus time for multiple points in the image and derive displacement signals for various physical locations in the survey region. These displacement signals are associated with seismic source firing times and locations before being stored as seismic traces in a survey database. Some variations use the reflected electromagnetic energy to create multiple interference patterns that vary due to different path length differences, thereby eliminating signal phase ambiguities. | 02-17-2011 |
20110038227 | SEISMIC DATA PROCESSING METHOD FOR SURFACE RELATED MULTIPLE ATTENUATION - An embodiment of the invention relates to a method of processing seismic data comprising a plurality of traces, each trace having a source position, a receiver position and a midpoint position, each having coordinates in an inline direction and a crossline direction. The invention uses a data set comprising traces having one of the source position, the receiver position or the midpoint position having coordinates which are invariant in one of the inline or the crossline directions. A non-iterative surface related multiple attenuation algorithm is applied to the data set which assumes substantial non-variation of depth of reflectors in the same one of the inline or the crossline directions. | 02-17-2011 |
20110063947 | ZERO OFFSET PROFILE FROM NEAR-FIELD HYDROPHONES - Method for acquiring zero offset data from a marine seismic survey. Seismic data are recorded using source signature monitor receivers located very near the air guns or other sources ( | 03-17-2011 |
20110085413 | Migration Velocity Analysis Using Seismic Data - A technique includes receiving seismic data acquired by an array of seismic sensors during a towed marine survey of a subsurface and performing migration velocity analysis to determine a background velocity model of the subsurface based at least in part on particle motion derived from the seismic data. | 04-14-2011 |
20110110188 | Seismic Data Acquisition and Source-Side Derivatives Generation and Application - 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. | 05-12-2011 |
20110149683 | Combined impulsive and non-impulsive seismic sources - A method for seismic exploration of subsurface rock formations includes actuating an impulsive seismic energy source proximate the rock formations. A non-impulsive seismic energy source is actuated. A near field waveform of each of the impulsive and non-impulsive seismic energy sources is detected. A far field waveform of the combined output of the impulsive and non-impulsive seismic energy sources is determined from the near field waveforms. An impulse response of the subsurface rock formations is determined by deconvolving the far field waveform with detected seismic signals. | 06-23-2011 |
20110176384 | Method and Device for Processing Seismic Data - Apparatus, computer instructions and method for processing seismic data related to a subsurface of a body of water. The method includes inputting data indicative of recordings made by detectors provided on a curved profile in response to an acoustic wave reflected from the subsurface; applying a matched mirror migration procedure to the data, where (i) actual positions of the detectors on the curved profile and corresponding recordings, and (ii) fictitious mirror positions of the actual detectors on the curved profile and corresponding recordings with a changed sign are added in the matched mirror migration; and generating a final image of the subsurface based on the matched mirror migration procedure. | 07-21-2011 |
20110211423 | Gravity Measurements Using Seismic Streamers - 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. | 09-01-2011 |
20110228636 | Cetacean Protection System - An embodiment according to one or more aspects of the present disclosure for conducting a marine survey includes a survey spread comprising a plurality of receivers and an energy source that is towed along a selected course while a signal is emitted from an energy source. A plurality of receivers receive data comprising a detection sampling frequency and a survey sampling frequency. The survey sampling frequency is monitored to detect a cetacean vocalization and to position the cetacean at least while conducting the seismic survey. Pursuant to the location of the cetacean actions can be taken to protect the cetacean and to minimize disruptions in conducting the seismic survey. | 09-22-2011 |
20110242935 | METHOD OF PROVIDING SEISMIC DATA - A method of providing seismic data (such as marine seismic data). A seismic source is actuated at a plurality of source locations (S | 10-06-2011 |
20110273958 | SYSTEM AND METHOD FOR ACCURATE DETERMINATION OF OCEAN BOTTOM SEISMOMETER POSITIONING AND TIMING - There is provided herein a system and method of seismic exploration that produces improved locations and timings for ocean bottom seismometers. The instant method utilizes linearized inversion in conjunction with a conventionally accurate clock to provide both time and positioning for each OBS unit with high accuracy as compared with the prior art approach. Inversion is one mathematical tool that effectively performs the requisite triangulation. Furthermore, the clock drift can be accounted for in the inversion scheme. The inversion not only determines the OBS position and shot timing errors, but also estimates the accuracy of the position and timing determination. | 11-10-2011 |
20110292761 | Method for building velocity models for imaging in multi-azimuth marine seismic surveys - A programmable computer is used to perform the following. 3D seismic data sets, corresponding to each azimuth in seismic data obtained from a multi-azimuth marine seismic survey, are migrated in grids oriented with the corresponding azimuth. Acquisition geometry is stored for each trace in the seismic data sets for each azimuth. Residual analysis, based on the corresponding azimuth, is performed on each of the migrated data sets, generating residuals and reflectors for each azimuth. The residuals and reflectors generated for each azimuth are rotated and merged on a master grid. Reflection tomographic inversion is applied iteratively to the rotated and merged residuals and reflectors to update a velocity model using the acquisition geometry as based on the master grid. The earth's subsurface is imaged using the updated velocity model. | 12-01-2011 |
20110299361 | APPARATUS AND METHOD FOR IMAGING SUBSURFACE STRUCTURE - The present invention relates to an imaging technique for modeling a subsurface structure through waveform inversion in the Laplace domain. According to the present invention, a source equivalent to the real source is calculated. The equivalent source is at least one source arranged on a virtual grid of the area to be measured, and the virtual grid has a large size which cannot be employed as the location of the real source in conventional techniques. The equivalent source has a vector obtained by multiplying an analytical solution vector and an impedance matrix of a Laplace domain wave equation, wherein said analytical solution vector is obtained from the analytical solution of a Laplace domain wave equation in a homogeneous half space by the real source. | 12-08-2011 |
20110310699 | REGULATING COHERENT BOUNDARY REFLECTIONS DURING GENERATION OF A MODELED WAVEFIELD - 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. | 12-22-2011 |
20110310700 | Seismic Data Acquisition and Source-Side Derivatives Generation and Application - 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. | 12-22-2011 |
20110317517 | Seismic data acquisition system with selectively enabled sensor units, and associated methods - A disclosed seismic survey system includes one or more streamer(s) each having multiple spaced apart sensor units, and a data recording and control system. Each sensor unit receives a command from the data recording and control system, and operates in an enabled state or a disabled state dependent upon the command. The data recording and control system collects and stores data from enabled sensor units. The sensor units produce data when in the enabled state, and dissipate significantly less electrical power in the disabled state. A described sensor unit includes one or more sensor(s), an analog-to-digital converter, and a control unit that enables or disables the analog-to-digital converter dependent upon the command. A disclosed method for acquiring seismic survey data includes issuing an enable or disable command to each of multiple spaced apart sensor units, and receiving and storing data from those sensor units that are enabled. | 12-29-2011 |
20120002504 | GRAVITY MEASUREMENTS IN MARINE, LAND AND/OR SEABED SEISMIC APPLICATIONS - A technique facilitates collection and use of data on subterranean formations. The technique comprises creating a distributed sensor network having multiple sensors arranged in a desired pattern. The distributed sensor network is employed to collect seismic data from the multiple sensors. Additionally, the distributed network and sensors are designed to collect gravity data from the multiple sensors. The sensors may be arranged in a variety of environments, including land-based environments and seabed environments. | 01-05-2012 |
20120008458 | METHOD TO ATTENUATE STRONG MARINE SEISMIC NOISE - Methods to attenuating strong marine seismic noises using singular value decomposition, determining noisiest traces and estimating noise components only from these traces, iteratively estimating the noise and protecting signal behind the noise. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72( | 01-12-2012 |
20120020186 | Seismic Imaging Systems and Methods Employing a Fast Target-Oriented Illumination Calculation - In various disclosed seismic imaging systems and methods, a fast target-oriented illumination calculation technique is employed to obtain a data volume or “matrix” of approximate illumination values. These illumination values enable an image matrix of “true reflectivity” values to be found. The illumination values are derived from Green's functions which, rather than being calculated and re-calculated on a shot-by-shot basis, are calculated in multi-shot groups and combined with a rolling-sum to greatly reduce the computational overhead. As a consequence, the disclosed systems and methods can provide target region illuminations more quickly and/or with higher quality than those systems relying on conventional 3D wave-equation illumination. | 01-26-2012 |
20120026829 | Method for wave decomposition using multi-component motion sensors - Three-axis velocity data, obtained along with pressure data in a marine seismic survey, are rotated to a ray direction. Plane wave decomposition is applied in the ray direction to the rotated velocity data. The pressure data and the velocity data are combined to generate at least one of up-going and down-going wave fields. The at least one of up-going and down-going wave fields are used in a time-space domain to image the earth's subsurface. | 02-02-2012 |
20120033526 | Wavefield deghosting of seismic data recorded using multiple seismic sources at different water depths - Seismic data are acquired by actuating a first source at a first time and one or more additional seismic sources each with their own characteristic times with respect to a time of signal recording, the sources substantially collocated and at different depths. A first wavefield is determined that would occur if the first source were actuated at a selected time with respect to an initiation time of the recordings and being time adjusted for the water depth. One or more additional wavefields are determined that would occur if the one or more additional sources were each actuated at said selected time with respect to said initiation time, and being time adjusted for water depths of the one or more additional sources. The first wavefield and the one or more additional wavefields are combined to determine a deghosted source wavefield corresponding to actuation of a single seismic energy source. | 02-09-2012 |
20120069704 | METHODS AND APPARATUS FOR DETERMINING SEISMIC STREAMER ARRAY GEOMETRY AND SEISMIC SENSOR RESPONSE - A method for marine seismic surveying includes determining at least an initial depth of a plurality of spaced apart seismic sensors in a body of water. The sensors each include a substantially collocated pressure responsive sensor and motion responsive sensor. A ghost time delay is determined for each sensor based on the at least an initial depth. Seismic signals detected by each motion responsive sensor and each pressure responsive sensor are cross ghosted. The at least initial depth is adjusted, and the determining ghost time delay and cross ghosted seismic signals are repeated until a difference between the cross ghosted motion responsive signal and the cross ghosted pressure responsive signal falls below a selected threshold. Other embodiments, aspects and features are also disclosed. | 03-22-2012 |
20120075950 | PROCESSING SEISMIC DATA - Embodiments of the invention provide a method of processing marine seismic data, the data having been acquired using a “dense over/sparse under” streamer array having N over streamers disposed at a first depth and M under streamers disposed at a second depth greater than the first depth, where 003-29-2012 | |
20120092957 | Survey Design for Sea Bottom Seismic in Shallow Water - The various embodiments herein provide a method to acquire seismic data to estimate reservoir characteristics in a shallow sea water environment. According to an embodiment herein, a method comprises acquiring four component ocean bottom cable (4C OBC) seismic data using a hydrophone and a three component geophone by varying a time delay between the shots and spacing between the shots. A full acoustic modelling process and an elastic modelling process are applied to the acquire 4C OBC seismic data to acquire a pressure data and an inline geophone data to estimate a horizontal component data and a reflected shear wave data. The estimated horizontal component data are NMO corrected and stacked by varying sampling intervals to remove noise component in the acquired seismic data. A shear wave energy data is estimated from the acquired pressure data to estimate shear wave properties of a sea bed and a subsurface carbonate reservoir. | 04-19-2012 |
20120099395 | DETECTING STRUCTURAL CHANGES TO UNDERWATER STRUCTURES - A method and system that can be used for scanning underwater structures. The method and system allow a user to gain a better understanding of an underwater structure. For example, the method and system detect change(s) to an underwater structure. An acoustic sonar wave is directed toward an underwater structure, and a reflected acoustic sonar wave is received and processed to produce a three dimensional image. Data points of this three-dimensional image of the underwater structure are aligned to a pre-existing three dimensional model of the underwater structure. A change detection model is generated based on the aligned 3D images, and the change detection model is compared to the pre-existing three dimensional model of the underwater structure. Based on the comparison, occurrences of structural changes in the underwater structure are detected. | 04-26-2012 |
20120113747 | Marine Vibroseis Motion Correction - A method for processing seismic data. The method includes receiving the seismic data acquired at one or more receivers due to one or more marine vibroseis sources that emit one or more vibroseis sweeps. The method then applies a receiver motion correction algorithm to the received seismic data to generate receiver motion corrected seismic data. After generating the receiver motion corrected seismic data, the method transforms the receiver motion corrected seismic data into a temporal Fourier domain to generate seismic data as a function of frequency. The method then reconstructs the transformed seismic data as a function of frequency to correct for one or more motions of the one or more marine vibroseis sources. After reconstructing the transformed seismic data, the method transforms the reconstructed seismic data to the time domain. The method then generates a seismic image of a subsurface of the Earth based on the transformed reconstructed seismic data. | 05-10-2012 |
20120113748 | Method to Improve Spatial Sampling of Vertical Motion of Seismic Wavefields on the Water Bottom by Utilizing Horizontal Rotational Motion and Vertical Motion Sensors - A method for spatial sampling of a seismic wavefield at the bottom of a water layer at an effective spatial sampling denser than the physical layout of the sensors. The sensors comprise a sensing element for vertical particle motion and a sensing element for rotational motion around a horizontal axis. Stress and wavefield conditions allow the rotational sensing element to yield the transverse horizontal gradient of the vertical particle motion wavefield, used in ordinate and slope sampling to yield improved transverse spatial sampling of the vertical particle motion wavefield. | 05-10-2012 |
20120134235 | Areal Marine Seismic Exploration Method - Autonomous self-pop-up multicomponent bottom nodes (self-pop-up nodes SPN) are deployed to the bottom of an exploration area along parallel lines of exploration at specified spaced points by a recording vessel. At least one seismic source mounted on a shooting vessel continuously fires seismic energy. The shooting vessel travels between the SPN deployment lines. The direction of the sailing direction is parallel to the aforesaid lines. A source vessel is initially located at a distance from the first SPN deployment line. Every SPN records seismic waves. Upon the source vessel passes the half of the lines, the recording vessel starts on-going relocation of the deployed SPNs to the next exploration lines starting with the SPNs on the first exploration line. Collection of SPNs occurs by the recording vessel equipped with a hydro-acoustic communication system with SPNs throughout its ongoing sailing along the SPNs deployment lines. Thereafter acquired data are processed. | 05-31-2012 |
20120163120 | PASSIVE NOISE CANCELLING PIEZOELECTRIC SENSOR APPARATUS AND METHOD OF USE THEREOF - Sensors used in mapping strata beneath a marine body and/or structures on a marine body floor are described, such as in a flexible buoyancy adjustable towed array. A first sensor is a traditional acoustic sensor or a novel acoustic sensor using a piezoelectric sensor mounted with a thin film separation layer of flexible microspheres on a rigid substrate. Additional non-acoustic sensors are optionally mounted on the rigid substrate for generation of output used to reduce noise observed by the acoustic sensors. Combinations of acoustic, non-acoustic, and motion sensors co-located in rigid streamer housing sections are provided, which reduce noise associated with different sensor locations and/or localized turbulence. | 06-28-2012 |
20120163121 | EXTRACTING SV SHEAR DATA FROM P-WAVE MARINE DATA - A system and method of processing seismic data obtained using a plurality of towed single-component receivers in a marine environment is described, the towed single-component receivers configured to measure compressional P waves. The method comprises retrieving seismic data from a storage device, the seismic data comprising P-P data and shear mode data, wherein the P-P data and shear mode data were both received at the towed single-component receivers configured to measure compressional P waves to generate the seismic data. The method further comprises processing the seismic data to extract SV-P shear mode data and generating shear mode image data based on the extracted shear mode data. | 06-28-2012 |
20120176861 | SHOT SCHEDULING LIMITS FOR SEISMIC ACQUISITION WITH SIMULTANEOUS SOURCE SHOOTING - According to an embodiment of the instant invention there is provided a method for collecting a blended source seismic survey that utilizes new approach to determining a random time separation between successive shots. The random time separation may be drawn in some embodiments from a distribution of uniformly distributed numbers, with τ>1/(2 f), where τ is the half-width of the uniform distribution and f is the lowest frequency of interest in the survey. | 07-12-2012 |
20120218859 | Method and Device for Processing Seismic Data - Apparatus, computer instructions and method for processing seismic data related to a subsurface of a body of water. The method includes inputting data indicative of recordings made by detectors provided on a depth-changing profile in response to an acoustic wave reflected from the subsurface; applying a matched mirror migration procedure to the data, where (i) actual positions of the detectors on the depth-changing profile and corresponding recordings, and (ii) fictitious mirror positions of the actual detectors on the depth-changing profile and corresponding recordings with a changed sign are added in the matched mirror migration; and generating a final image of the subsurface based on the matched mirror migration procedure. | 08-30-2012 |
20120287753 | SEISMIC CLOCK TIMING CORRECTION USING OCEAN ACOUSTIC WAVES - A method for identifying clock timing discrepancies in a plurality of clocks that are each associated with a seismic receiver, comprises the steps of collecting from at least a pair of receivers a data set corresponding to a selected time period, cross-correlating the data sets between at least one pair of receivers so as to produce cross-correlated data for positive, zero, and negative time lags, comparing the cross-correlated data for the positive and negative time lags to measure a timing asymmetry about the zero-lag time, and, for a receiver pair for which there is a non-zero timing asymmetry, using the asymmetry to identify a timing discrepancy between the clocks associated with that receiver pair. The each data set can be filtered so as to obtain data in a selected frequency range, which may avoid an active shot frequency. The data may be collected in the absence of active seismic shots. | 11-15-2012 |
20120307591 | METHODS AND APPARATUS FOR SEISMIC EXPLORATION USING PRESSURE CHANGES CAUSED BY SEA-SURFACE VARIATIONS - Disclosed are apparatus and methods for seismic exploration using pressure changes caused by sea-surface variations as a low-frequency seismic energy source. One embodiment relates to a method which obtains dual wave-fields measured below a sea surface. The measured dual wave-fields are decomposed into a down-going wave-field and an up-going wave-field at a selected observation level. Seismic images are then generated using the down-going and up-going wave-fields. Other embodiments, aspects, and features are also disclosed. | 12-06-2012 |
20130003498 | METHOD FOR ESTIMATING AN UNDERWATER ACOUSTIC SOUND VELOCITY IN A NETWORK OF ACOUSTIC NODES, CORRESPONDING COMPUTER PROGRAM PRODUCT, STORAGE MEANS AND DEVICE - A method for estimating an underwater acoustic sound velocity in a network of acoustic nodes arranged along towed acoustic linear antennas and in which a plurality of acoustic signals are transmitted between the nodes. The method includes: obtaining two predetermined distances each separating a couple of nodes placed along a same first acoustic linear antenna ( | 01-03-2013 |
20130028048 | METHODS AND APPARATUS FOR SEISMIC IMAGING WHICH ACCOUNTS FOR SEA-SURFACE VARIATIONS - Disclosed are apparatus and methods for seismic imaging which accounts for sea-surface variations. In accordance with one embodiment, a source wave-field is forward propagated to a subsurface level below a sea floor. In addition, a receiver wave-field is backward propagated to the subsurface level, wherein the backward propagation in time comprises synchronized backward running of the sea surface. Other embodiments, aspects, and features are also disclosed. | 01-31-2013 |
20130114375 | Seismic Acquisition Method for Mode Separation - Method for separating different seismic energy modes in the acquisition ( | 05-09-2013 |
20130121108 | ROTATIONAL MOTION COMPENSATED SEISMIC SENSORS AND METHODS OF USE IN SEISMIC DATA ACQUISITION - Apparatus and methods for acquiring seismic data using a seabed seismic data cable positioned on a seabed are described, including correcting for the effect of one or more sensor non-linear motions, which improves accuracy of seismic data. One or multiple non-linear movements of the sensor may be corrected for. It is emphasized that this abstract is provided to comply with the rules requiring an abstract, which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. | 05-16-2013 |
20130128692 | EXTRACTING SV SHEAR DATA FROM P-WAVE MARINE DATA - A system and method of processing seismic data obtained using a plurality of towed single-component receivers in a marine environment is described, the towed single-component receivers configured to measure compressional P waves. The method comprises retrieving seismic data from a storage device, the seismic data comprising P-P data and shear mode data, wherein the P-P data and shear mode data were both received at the towed single-component receivers configured to measure compressional P waves to generate the seismic data. The method further comprises processing the seismic data to extract SV-P shear mode data and generating shear mode image data based on the extracted shear mode data. | 05-23-2013 |
20130135965 | SEPARATION OF SIMULTANEOUS SOURCE DATA - Generating an image of an interior of the Earth from a seismic survey using multiple sources. The multiple sources may be fired simultaneously and the data received by seismic sensors in the seismic survey may be decomposed so that seismic data generated by each of the multiple sources may be determined. Decomposing of the received data may be performed using frequency diverse basis functions and converting the data separation problem into an optimization problem, which can be a one-norm or zero-norm optimization problem in frequency-space domain. The decomposed data may be used to generate the image of the Earth's interior. | 05-30-2013 |
20130182532 | PROCESSING COLLECTED SURVEY DATA - A method to perform a marine seismic survey includes obtaining marine seismic data corresponding to a subterranean formation under a water surface. The marine seismic data is generated from an underwater seismic sensor that is subject to an interference effect. The method further includes generating, by a computer processor and using a deconvolution operation, corrected marine seismic data based at least in part on the marine seismic data to compensate for the interference effect, and generating, by the computer processor, a marine seismic survey result based at least in part on the corrected marine seismic data. | 07-18-2013 |
20130286775 | SEISMIC IMAGING SYSTEM FOR COUSTIC-ELASTIC COUPLED MEDIA USING ACCUMULATED LAPLACE GRADIENT DIRECTION - The description relates to a seismic imaging technology technique for modeling a subsurface structure through waveform inversion in the Laplace domain. The seismic imaging system comprises a scaled gradient calculating unit calculating a scaled gradient, a modeling parameter updating unit updating the model parameters using the scaled gradient direction, and an iteration control unit controlling the scaled gradient calculating unit and the modeling parameter updating unit to repeat processing iteratively until a stopping criteria is met. | 10-31-2013 |
20130343153 | MARINE VIBRATOR SWEEPS WITH REDUCED SMEARING AND/OR INCREASED DISTORTION TOLERANCE - A marine seismic survey using one or more moving marine seismic vibrators, where the vibrator sweeping function is based on smearing error criteria and is a downward-sweeping non-criteria linear sweep function. The acquired seismic data can either be used as is without desmearing or desmeared easily. | 12-26-2013 |
20140016434 | METHOD AND SYSTEM OF CONTROLLING TOWING SPEED OF A SENSOR STREAMER - Controlling towing speed of a sensor streamer. At least some of the of the embodiments are methods including: towing a sensor streamer through water at a towing speed; releasing interrogating energy within the water; recording energy received by the sensor streamer to create recorded energy; determining a value indicative of noise within the recorded energy; and changing the towing speed in real-time responsive to the value indicative of noise within the recorded energy. | 01-16-2014 |
20140043936 | DEVICE AND METHOD FOR DIRECTIONAL DESIGNATURE OF SEISMIC DATA - Computing device, computer instructions and method for directional designature of seismic data d with a given source directivity. The method includes obtaining directional operators r; calculating a model u with a modified source directivity based on (1) seismic data d, and (2) an operator that is a combination of the directional operators r and a reverse transform operator L; using the model u to obtain seismic data d | 02-13-2014 |
20140086008 | INVERSE TIMING METHOD, APPARATUS, AND APPLICATIONS - An ‘inverse timing’ method advantageously utilized for marine seismic applications involving one or more autonomous nodes involves the step of synchronizing the timing of newly recorded and/or prior recorded seismic data with a ‘true’ time whereby the synchronizing of timing is performed in a non-traditional ‘reverse’ manner rather than the traditional manner that is performed prior to recording the seismic survey data. | 03-27-2014 |
20140104985 | MARINE SEISMIC SURVEYING IN ICY OR OBSTRUCTED WATERS - A skeg mounts from the stern of a towing vessel and extends below the waterline. A channel in the skeg protects cables for steamers and a source of a seismic system deployed from the vessel. Tow points on the skeg lie below the water's surface and connect to towlines to support the steamers and source. A floatation device supports the source and tows below the water's surface to avoid ice floes. The streamers can have vehicles deployed thereon for controlling a position on the streamer. To facilitate locating the streamers, these vehicles on the streamers can be brought to the surface when clear of ice floes so that GPS readings can be obtained and communicated to a control system. After obtaining readings, the vehicles can be floated back under the surface. Deploying, using, and retrieving the system accounts for ice at the surface in icy regions. In addition, handling the seismic record can account for noise generated by ice impact events. | 04-17-2014 |
20140133271 | PROCESS FOR SEPARATING DATA RECORDED DURING A CONTINUOUS DATA ACQUISITION SEISMIC SURVEY - Method for separating signals recorded by a seismic receiver and generated with at least two vibratory seismic sources driven with no listening time. The method includes receiving seismic data that includes data d recorded by the seismic receiver and data related to the first and second vibratory seismic sources; computing a source separation matrix based on the data related to the first and second vibratory seismic sources; calculating first and second earth impulse responses HA and HB corresponding to the two vibratory seismic sources, respectively, based on the data d recorded by the seismic receiver, the data related to the two vibratory seismic sources and the source separation matrix; and separating the signals recorded by the seismic receiver based on the first and second earth impulse responses HA and HB such that signals the two vibratory seismic sources are disentangled. | 05-15-2014 |
20140140171 | METHODS AND SYSTEMS FOR EXTRAPOLATING WAVEFIELDS - Methods and Systems for extrapolating wavefields while avoiding disruptions due to spatial aliasing are disclosed. Pressure wavefields measured with pressure sensors and vertical and horizontal velocity wavefields measured with three-axial motions sensors may be spatially aliased in at least one horizontal direction. The pressure wavefield and/or the vertical velocity wavefield are decomposed into one of an up-going wavefield and a down-going wavefield. The up-going or down-going wavefield is extrapolated using an extrapolator that depends on components of a slowness vector. In order to avoid disruptions in the extrapolated wavefield due to spatial aliasing, the components of the slowness vector are calculated from the measured pressure wavefield and the two horizontal velocity wavefields. | 05-22-2014 |
20140160887 | TIME LAPSE MARINE SEISMIC SURVEYING EMPLOYING INTERPOLATED MULTICOMPONENT STREAMER PRESSURE DATA - In a first aspect, a method for use in a time lapse, marine seismic survey includes accessing a set of acquired, multicomponent seismic data; and interpolating a set of time lapse seismic data from the acquired seismic data. In other aspects, a program storage medium is encoded with instructions that, when executed by a computing device, perform the above method and a computing apparatus programmed to perform one or more of such methods. | 06-12-2014 |
20140211590 | PROCESS FOR SEPARATING DATA RECORDED DURING A CONTINUOUS DATA ACQUISITION SEISMIC SURVEY - Method for separating signals recorded by a seismic receiver and generated with at least two vibratory seismic sources driven with no listening time. The method includes receiving seismic data that includes data d recorded by the seismic receiver and data related to the first and second vibratory seismic sources; computing a source separation matrix based on the data related to the first and second vibratory seismic sources; calculating first and second earth impulse responses HA and HB corresponding to the two vibratory seismic sources, respectively, based on the data d recorded by the seismic receiver, the data related to the two vibratory seismic sources and the source separation matrix; and separating the signals recorded by the seismic receiver based on the first and second earth impulse responses HA and HB such that signals the two vibratory seismic sources are disentangled. | 07-31-2014 |
20140254317 | Correlation Techniques for Passive Electroseismic and Seismoelectric Surveying - A method for surveying, may include receiving, by a processor, first survey data from a first source, the first source comprising a first signal generated by a subsurface earth formation in response to a passive-source electromagnetic signal, wherein the electromagnetic signal is generated by an electroseismic or seismoelectric conversion of the passive-source electromagnetic signal. The method may also include receiving, by the processor, second survey data from a second source and processing the first survey data and the second survey data to determine one or more properties of a subsurface earth formation. | 09-11-2014 |
20140269180 | Gravity Measurements By Towed Streamers - Techniques are described for measuring gravity using towed streamers. In an embodiment, a towed streamer apparatus comprises a plurality of micro electro-mechanical system (MEMS) sensors. One or more MEMS sensors of the plurality of MEMS sensors are configured to generate gravity measurement data. The one or more MEMS sensors transmit a digitized version of the gravity measurement data to a processing unit. In another embodiment, an apparatus is configured to receive gravity measurement data via an interface that is communicatively coupled to a plurality of MEMS sensors in at least one towed streamer. The apparatus may further be configured to combine the gravity measurement data received from the plurality of MEMS sensors to compute a target gravity measurement value and detect changes in gravity based on the target gravity measurement value. | 09-18-2014 |
20140269181 | METHODS AND SYSTEMS FOR INTERPOLATION OF MULTI-COMPONENT SEISMIC DATA COLLECTED IN A MARINE ENVIRONMENT - Computational systems and methods for interpolating a pressure wavefield based on pressure wavefield and particle motion wavefield data are disclosed. The pressure and particle motion wavefields are sampled at a sample rate that is less than a lower bound for sample rates typically used to interpolate the pressure wavefield from the pressure wavefield samples alone. The particle motion wavefield can an acceleration wavefield or a time derivative of a velocity wavefield. | 09-18-2014 |
20140293743 | MARINE SEISMIC SURVEYING EMPLOYING INTERPOLATED MULTICOMPONENT STREAMER PRESSURE DATA - It is described a method of interpolating and extrapolating seismic recordings, including the steps of deriving particle velocity related data from seismic recordings obtained by at least one streamer carrying a plurality of multi-component receivers and using the particle velocity related data to replace higher derivatives of pressure data in an expansion series. | 10-02-2014 |
20140313854 | METHOD AND DEVICE FOR PROCESSING SEISMIC DATA - Apparatus, computer instructions and method for processing seismic data related to a subsurface of a body of water. The method includes inputting data indicative of recordings made by detectors disposed on a depth-changing profile in response to an acoustic wave reflected from the subsurface; applying a matched mirror migration procedure to the data, wherein the matched mirror migration procedure uses an up-traveling U wave and a down-traveling D wave, at least one of the up-traveling U wave or the down-traveling D wave being constructed based on (i) actual positions of the detectors disposed on the depth-changing profile and corresponding recordings, and (ii) fictitious mirror positions of the actual detectors on the depth-changing profile and corresponding recordings with a changed sign; and generating in a processor an image of the subsurface based on the matched mirror migration procedure. | 10-23-2014 |
20140321239 | SEISMIC DATA ACQUISITION AND SOURCE-SIDE DERIVATIVES GENERATION AND APPLICATION - 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. | 10-30-2014 |
20140334259 | Variable Mass Load Marine Vibrator - Embodiments related to addition of a variable mass load to the shell of a marine vibrator to compensate for air spring effects. An embodiment provides a marine vibrator, comprising: an outer shell; a driver disposed at least partially within the outer shell and coupled thereto; and a mass load coupled to an exterior surface of the outer shell; wherein the marine vibrator has a resonance frequency selectable based at least in part on the mass load. | 11-13-2014 |
20140340987 | NOISE MODELS BY SELECTION OF TRANSFORM COEFFICIENTS - A data set representing features of a geologic formation is formed from two or more signal acquisition data set representing independent aspects of the same wavefield. A wavelet transform is performed on the two or more signal acquisition data sets, and the data sets are further transformed to equalize signal portions of the data sets. Remaining differences in the data sets are interpreted as excess noise and are removed by different methods to improve the signal-to-noise ratio of any resulting data set. | 11-20-2014 |
20140362663 | SIMULTANEOUS SOURCE MARINE SEISMIC ACQUISITION - Methods and apparatuses for acquiring marine seismic data to generate images or determine properties of an interior section of the Earth using vessels ing simultaneous sources. The time required to acquire a seismic survey is decreased by increasing the speed of the source towing vessel (or decreasing the data sampling density, or increased sampling interval) using multiple simultaneous sources. After separation with simultaneous source technique and combination of separated datasets, seismic data with designed data sampling density or better are acquired. | 12-11-2014 |
20150063064 | METHODS AND SYSTEMS FOR ATTENUATING NOISE IN SEISMIC DATA - The disclosure presents computational systems and methods for attenuating noise in seismic data. The seismic data may be recorded by distributed sensors in response to acoustic signals emanating from one or more sources activated at approximately the same location with a time delay between activations of the one or more sources. The system and methods form an initial gather of traces from the seismic data and generate time-shifted gathers based on the initial gather and the time delays between activation of the sources. A realization gather is formed from traces selected from the initial gather and the time-shifted gathers. Noise in the seismic data is attenuated in the realization gather and may be removed. The realizations gathers may be used to generate high-resolution seismic images of the subterranean formation and enable quantitative seismic interpretation and improved reservoir monitoring. | 03-05-2015 |
20150071032 | SOURCE UMBILICAL CABLE WITHOUT FUNCTIONING POWER CABLES - Techniques are disclosed relating to the operation of a source umbilical cable without functioning power cables from the source umbilical cable. Techniques are disclosed relating to a source umbilical cable without a power cable (e.g., a cable configured or operable to supply electrical power), and an apparatus that includes a geophysical signal source (e.g., a seismic signal source) with an electrical power generating component. The apparatus may, in one embodiment, include a geophysical signal source with a local generator configured to supply electrical power to electrical components of the geophysical signal source. In another embodiment where the geophysical signal source is being towed behind a vessel, a generator of the geophysical signal source may generate and supply electrical power based on motion of the generator through a body of water. | 03-12-2015 |
20150071033 | Correlation Techniques for Passive Electroseismic and Seismoelectric Surveying - A method for surveying, may include receiving, by a processor, first survey data from a first source, the first source comprising a first signal generated by a subsurface earth formation in response to a passive-source electromagnetic signal, wherein the electromagnetic signal is generated by an electroseismic or seismoelectric conversion of the passive-source electromagnetic signal. The method may also include receiving, by the processor, second survey data from a second source and processing the first survey data and the second survey data to determine one or more properties of a subsurface earth formation. | 03-12-2015 |
20160003958 | INTERFERENCE ATTENUATION OF A RESIDUAL PORTION OF SEISMIC DATA - The present disclosure is related to methods, systems, and machine-readable media for interference attenuation of a residual portion of seismic data, such as may be recorded in a marine seismic survey. Recorded seismic data can be separated into a portion attributed to a source and a residual portion. Seismic interference attenuation can be performed on the residual portion. | 01-07-2016 |
20160018540 | Independent Simultaneous Shooting Acquisition With Vertical Seismic Profile Recording - A method for use in vertical seismic profiling includes: independently and simultaneously shooting a plurality of seismic sources in a plurality of shooting areas to impart seismic signals into a water bottom: receiving reflections of the seismic signals from a subterranean formation beneath the water bottom at a plurality of seismic receivers; and recording the received reflections; wherein, one of the seismic sources and the seismic receivers are disposed in a wellbore in the water bottom. | 01-21-2016 |
20160018544 | MARINE VIBRATOR DOPPLER CORRECTION - A method of processing seismic survey data includes: receiving seismic signatures emitted from a plurality of seismic sources during a frequency sweep as the sources are moved over a shot point; receiving a seismic trace generated by a seismic receiver, the seismic trace representing seismic signals resulting at least in part from the seismic signatures reflecting from an earth formation; performing an inversion of the seismic trace with the seismic signatures to separate the seismic trace into individual seismic signals, each of the individual seismic signals associated with a respective seismic source, wherein the inversion includes transforming the seismic trace to a frequency domain and generating frequency domain signals for multiple frequency bands in the frequency sweep; and during the inversion, applying a receiver motion correction to the frequency domain signals, and applying a Doppler correction to the frequency domain signals to correct for Doppler effects due to source motion. | 01-21-2016 |
20160109591 | NOISE MODEL ESTIMATION IN MULTIMEASUREMENT DATA - Various implementations described herein are directed to methods for processing seismic data, including estimating a spectral noise power of multi-measurement seismic data received from a multi-dimensional seismic sensor array having multiple seismic sensors. The methods may include receiving a shot record of multi-measurement seismic data in time-domain, partitioning the shot record into overlapping time-space windows, and computing a frequency-domain spectrum for each time-space window. The methods may include computing a signal presence probability for each time-space window using the frequency-domain spectrum and prior probabilities of signal presence and absence for each time-space window. The methods may include iteratively updating a collective spectral noise power by recursively estimating the spectral noise power of a current time-space window based on the frequency spectrum for the current time-space window, the signal presence probability computed for the current time-space window, and a previously estimated spectral noise power of a previous time-space window. | 04-21-2016 |
20160109598 | METHODS AND SYSTEMS TO SEPARATE SEISMIC DATA ASSOCIATED WITH IMPULSIVE AND NON-IMPULSIVE SOURCES - Methods and systems to separate seismic data associated with impulsive and non-impulsive sources are described. The impulsive and non-impulsive sources may be towed through a body of water by separate survey vessels. Receivers of one or more streamers towed through the body of water above a subterranean formation generate seismic data that represents a reflected wavefield produced by the subterranean formation in response to separate source wavefields generated by simultaneous activation of the impulsive source and the non-impulsive source. Methods and systems include separating the seismic data into impulsive source seismic data associated with the impulsive source and non-impulsive source seismic data associated with the non-impulsive. | 04-21-2016 |
20160131783 | BIO-ACOUSTIC SENSING DEVICE AND METHOD FOR MARINE SEISMIC SURVEY - A method and marine seismic processing system including an interface for receiving recorded data, wherein the recorded data includes seismic data and bio-acoustic data; a seismic data processor for estimating a source signature from the recorded data, wherein the source signature is associated with a seismic source that emits seismic waves in water during a seismic survey; and a bio-acoustic processor that estimates a presence of a mammal generating the bio-acoustic data, based on a processed signal obtained by removing the source signature from the recorded data. | 05-12-2016 |
20160131786 | METHODS AND DEVICES FOR ACQUIRING SEISMIC DATA RELATIVE TO AN UNDERGROUND AREA BENEATH THE SEA - In order to acquire seismic data relative to an underground area beneath the sea, seismic waves are emitted in an emission direction forming an angle θ with the vertical using, at least one seismic source submerged at a depth d. A seismic signal is collected following the emission of the seismic waves and the propagation of same underground with a view to processing same. In one embodiment of the method, in order to overcome the major problem linked to the depth limit encountered by seismic sources, the processing of the seismic signal comprises a summation of a plurality of terms including the seismic signal and the seismic signal delayed by ΔT=2d·cos θ/V, in which V is the speed of propagation of the seismic waves in water. | 05-12-2016 |
20160187511 | PULSED MARINE SOURCE - Systems and methods for generating seismic signal include using a conventional airgun array and specifically detunes the timing of the array so individual airguns are not fired at the same time and with their interacting bubbles form a unique composite pulse that can be separated by various means out of a seismic record to form the shotpoint. The advantage of this approach is a lower overall noise envelope in the water minimizing impact on the marine mammals and it allows multiple arrays to be fired in close spatial and timing proximity with minimal to no interference. | 06-30-2016 |
20160202378 | METHOD AND SYSTEM OF MULTI-SOURCE MARINE SEISMIC SURVEYING | 07-14-2016 |
20160202379 | METHODS AND SYSTEMS FOR SEISMIC IMAGING USING CODED DIRECTIVITY | 07-14-2016 |
20190146112 | METHOD FOR DETERMINING SENSOR DEPTHS AND QUALITY CONTROL OF SENSOR DEPTHS FOR SEISMIC DATA PROCESSING | 05-16-2019 |