Patent application number | Description | Published |
20090010103 | EFFICIENT SEISMIC DATA ACQUISITION WITH SOURCE SEPARATION - A method for the simultaneous operation of multiple seismic vibrators using unique modified pseudorandom sweeps and recovery of the transmission path response from each vibrator is disclosed. The vibrator sweeps are derived from pseudorandom binary sequences modified to be weakly correlated over a time window of interest, spectrally shaped and amplitude level compressed. Cross-correlation with each pilot signal is used to perform an initial separation of the composite received signal data set. Recordings of the motion of each vibrator are also cross-correlated with each pilot, windowed, and transformed to form a source cross-spectral density matrix in the frequency domain useful for source signature removal and for additional crosstalk-suppression between the separated records. After source signature removal in the frequency domain an inverse transform is applied to produce an estimate of each source-to-receiver earth response in the time domain. The method has application to both land and marine geophysical exploration. | 01-08-2009 |
20110085416 | SYSTEM AND METHOD FOR DETERMINING A FREQUENCY SWEEP FOR SEISMIC ANALYSIS - A sweep generator is employed to generate a sweep to be used by a seismic vibrator device for generating a desired target output spectrum, wherein the frequency sweep is designed so as to comply with one or more constraints imposed by the seismic vibrator device and/or imposed by the environment in which the device is to be used. In one embodiment, a sweep generator determines a sweep for achieving a desired target output spectrum by a given seismic vibrator device in compliance with at least a pump flow constraint imposed by the seismic vibrator device. In another embodiment, a sweep generator determines a sweep for achieving a desired target output spectrum by a given seismic vibrator device in compliance with all of multiple operational constraints of the seismic vibrator device, such as both mass displacement and pump flow constraints. Environmental constraints may also be accounted for in certain embodiments. | 04-14-2011 |
20120307597 | SYSTEM AND METHOD FOR DETERMINING A FREQUENCY SWEEP FOR SEISMIC ANALYSIS - A sweep generator is employed to generate a sweep to be used by a seismic vibrator device for generating a desired target output spectrum, wherein the frequency sweep is designed so as to comply with one or more constraints imposed by the seismic vibrator device and/or imposed by the environment in which the device is to be used. In one embodiment, a sweep generator determines a sweep for achieving a desired target output spectrum by a given seismic vibrator device in compliance with at least a pump flow constraint imposed by the seismic vibrator device. In another embodiment, a sweep generator determines a sweep for achieving a desired target output spectrum by a given seismic vibrator device in compliance with all of multiple operational constraints of the seismic vibrator device, such as both mass displacement and pump flow constraints. Environmental constraints may also be accounted for in certain embodiments. | 12-06-2012 |
20130163380 | LOW-FREQUENCY CONTENT BOOST FOR VIBRATORY SEISMIC SOURCE AND METHOD - Computer software, computer and method for generating with a computing device a desired pilot signal for driving a vibratory source to generate seismic waves. The method includes steps for compressing a pilot signal in a force domain and also compressing a mass displacement in a displacement domain. The resulting desired pilot signal boosts the low-frequency end of the vibratory source. | 06-27-2013 |
20130163381 | METHOD AND SEISMIC SOURCES WITH HIGH PRODUCTIVITY - A method for seismic prospecting that includes a step of deploying plural vibratory sources on the ground; a step of receiving at each vibratory source a corresponding pilot signal for driving the vibratory source; a step of asynchronously actuating the vibratory sources to generate seismic waves into the ground; and a step of continuously recording seismic signals produced by the seismic waves. Pilot signals for the plural vibratory sources are obtained by spectrally shaping starting sequences into continuous pseudorandom sequences that are weakly correlated over a predetermined time interval. | 06-27-2013 |
20130163385 | HIGH-FREQUENCY CONTENT BOOST FOR VIBRATORY SEISMIC SOURCE AND METHOD - Computer software, controller and method for generating a desired pilot signal for driving a vibratory source. The method includes steps for selecting a pilot target amplitude spectrum for the vibratory source; determining an initial pilot signal that matches the pilot target amplitude spectrum; associating the initial pilot signal with first and second frequency bands, the second frequency band including a high-frequency end of a range of the vibratory source; band-passing a first part of the initial pilot signal associated with the first frequency band with a first band-pass configuration; band-passing a second part of the initial pilot signal associated with the second frequency band with a second band-pass configuration; level compressing the first and second parts of the initial pilot signal; recombining the first and second parts of the initial pilot signal to form a recombined pilot signal; and processing the recombined pilot signal to obtain the desired pilot signal. | 06-27-2013 |
20130163386 | BURIED PRESSURIZED VOLUMETRIC SOURCE AND METHOD - A seismic source configured to generate seismic waves underground. The source includes a tank configured to be buried underground, the tank having a cavity; an actuation mechanism provided inside the cavity, wherein the actuation mechanism is configured to have at least one movable part that moves back and forth to generate a seismic wave having a desired frequency; and a first fluid provided inside the cavity and around the actuation mechanism and configured to transform the back and forth movement of the at least one movable part into a varying pressure that directly acts on walls of the tank. | 06-27-2013 |
20140003197 | SYSTEM AND METHOD FOR DETERMINING A FREQUENCY SWEEP FOR SEISMIC ANALYSIS | 01-02-2014 |