Abstract: A method for performing a seismic survey using at least one carrier which includes a seismic source. The method includes: deploying each of the at least one carriers by the delivery vehicle, wherein each of the at least one carriers includes: a plurality of supports configured to enable a baseplate to contact ground, wherein the baseplate is formed by each foot of the plurality of supports; a seismic source which includes a lower portion configured to push through unconsolidated materials and configured to contact the ground; and a power source configured to operate the seismic source; and transmitting at least one seismic signal from the seismic source.

Abstract: A system and method for reducing noise in a seismic vibratory source is disclosed. The method includes generating an initial pilot signal for the seismic vibratory source, receiving a source signature based on the initial pilot signal, estimating a noise component of the source signature based on the source signature and the initial pilot signal, generating an anti-noise correction for the initial pilot signal based on the noise component of the source signature, and computing a modified pilot signal based on the initial pilot signal and the anti-noise correction.

Abstract: Method and resonant source for generating low-frequency seismic waves. The resonant source includes a frame; a reaction mass configured to oscillate relative to the frame; a resonant suspension system connecting the reaction mass to the frame and including at least a spring; and a spring clamp system connected to the resonant suspension system and configured to modify a resonant frequency of the resonant suspension system. The resonant suspension system is configured to allow the reaction mass to oscillate relative to the frame with a corresponding resonant frequency.

Abstract: A system and method for reducing noise in a seismic vibratory source is disclosed. The method includes generating an initial pilot signal for the seismic vibratory source, receiving a source signature based on the initial pilot signal, estimating a noise component of the source signature based on the source signature and the initial pilot signal, generating an anti-noise correction for the initial pilot signal based on the noise component of the source signature, and computing a modified pilot signal based on the initial pilot signal and the anti-noise correction.

Abstract: Methods and systems for separating seismic data acquired using a plurality of substantially simultaneously fired sources are described. The sources use sweep sequences having low cross correlation levels to generate seismic waves, and their source signatures are determined. Using the source signatures, the wave fields associated with each of the sources are extracted from the seismic data by, for example, performing a time domain deconvolution.

Abstract: Computing device, computer software and methods for generating sweep signals corresponding to plural sources that generate seismic waves. The method includes selecting (502) a nominal sweep signal (S0); applying (512) a perturbation (P) to the nominal sweep signal (S0); and calculating (518) the sweep signals (Sn) by varying the perturbation (P), each sweep signal corresponding to a seismic source.

Abstract: Methods for seismic exploration of a subsurface formation increase productivity by simultaneously actuating closely located vibratory sources. Individual vibrations generated by different sources actuated simultaneously are encoded to enable separation of seismic data corresponding to each of the individual vibrations.

Abstract: Methods and systems for deriving S-wave velocity information from the low-frequency content of ambient noise are described. The ambient noise can be collected on a dedicated record or on a production record associated with the receivers of a three-dimensional seismic survey. The methods and systems use one of a plurality of analysis models selected based on quality factors of the ambient noise data. The methods and systems analyze the data at a plurality of single frequencies then transform the velocity versus frequency data into velocity versus depth data.

Abstract: Method, computer device and software for calculating a corrected temporal variation (dt1)depth or a corrected relative temporal variation (dt1/t1)depth of a first body wave based on a second body wave. The method includes receiving raw seismic data recorded with a receiver; calculating arrival-time variations for the first and second body waves; calculating first and second relative temporal variations for the first and second body waves; and correcting the first relative temporal variation based on the second relative temporal variation to obtain the corrected relative temporal variation or correcting the first temporal variation based on the second temporal variation to obtain the corrected temporal variation. The second wave is either a body wave or a surface wave.

Abstract: Method and system for determining positions of underwater sensors. The method includes sending a Doppler variant signal from a moving source; recording the signal with the at least one seismic sensor; evaluating a frequency drift of the recorded signal; and determining a position of the at least one seismic sensor based on the evaluated frequency drift and a source movement relative to the at least one sensor.

Abstract: An apparatus for automated seismic sensing includes a seismic sensing device for sensing seismic vibrations, a robotic transport unit for transporting the seismic sensing device to a targeted location, an engagement unit for placing the seismic sensing device in vibrational communication with the ground, and a recording module for recording the seismic data generated by the seismic sensing device. A corresponding method for automated seismic sensing includes transporting a seismic sensing device to a targeted location with a robotic transport device, determining a coupling metric for the seismic sensing device and the ground at a plurality of locations proximate to the targeted location, determining an acceptable location for seismic sensing, placing the seismic sensing device in vibrational communication with the ground at the acceptable location, and sensing seismic data with the seismic sensing device at the acceptable location.

Abstract: A method for improving a 4-dimensional (4D) repeatability by modifying a given path to be followed by a source during a seismic survey. The method includes receiving the given path at a control device associated with a vehicle that caries the source; following the given path during a first seismic survey that is a baseline survey for the 4D seismic survey; deviating from the given path to follow a new path when encountering an obstacle on the given path; and updating the given path, based on the new path, to obtain an updated given path when a deviation condition is met.

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

Abstract: Method, computer device and software for calculating a corrected temporal variation (dt1)depth or a corrected relative temporal variation (dt1/t1)depth of a first body wave based on a second body wave. The method includes receiving raw seismic data recorded with a receiver; calculating arrival-time variations for the first and second body waves; calculating first and second relative temporal variations for the first and second body waves; and correcting the first relative temporal variation based on the second relative temporal variation to obtain the corrected relative temporal variation or correcting the first temporal variation based on the second temporal variation to obtain the corrected temporal variation. The second wave is either a body wave or a surface wave.

Abstract: Method and system for determining positions of underwater sensors. The method includes sending a Doppler variant signal from a moving source; recording the signal with the at least one seismic sensor; evaluating a frequency drift of the recorded signal; and determining a position of the at least one seismic sensor based on the evaluated frequency drift and a source movement relative to the at least one sensor.

Abstract: The invention relates to a vibroseis analysis method in which frequency-sweep signals (10) are emitted into a subsurface, the signals reflected on the substrata of such a subsurface (10, 20) are logged and the logged signals are processed, a method in which the harmonics (20) of the fundamental signal (10) initially emitted are eliminated from the logged signals, by applying the steps consisting in: a) providing a time/frequency plot, showing the respective contributions of the fundamental (10) and of the harmonics (20) in the logged signal, b) providing a time/frequency plot also showing these contributions of the fundamental (10) and of the harmonics (20) in the logged signal, this plot having been stretched in the direction of the frequency axis such that the fundamental (10) of this plot is over the location of a harmonic (20) chosen from the plot; c) adapting the power amplitude of this stretched plot to make this amplitude correspond to that of the said chosen harmonic (20) of the plot; d) subtracti

Abstract: A method for making o- and p- halomethyl styrenes which comprises reacting an ethyl benzene, paraformaldehyde and hydrogen halide, treating the reaction product with a halogen, and dehydrohalogenating the resulting o- and p- halomethyl (1-haloethyl) benzenes at an elevated temperature using as dehydrohalogenating agent an amine acceptor of the generic formula: ##STR1## WHEREIN R is an alkyl group of 1 to 6 carbon atoms, n is an integer having a value of from 1 to 5, and at least one alkyl group is attached to a carbon atom adjacent to the nitrogen atom and when n is more than 1, the alkyl groups may be the same or different groups, and recovering a mixture of o- and p- halomethyl styrenes.