Abstract: Seismic data are acquired using a seismic source comprising a plurality of seismic sub-sources disposed in a body of water at a plurality of depths and activated with different time delays. Far-field signatures are determined for the plurality of seismic sub-sources at each of the plurality of depths. A composite ghost-free far-field signature of the seismic source is determined from the far-field signatures for the plurality of seismic sub-sources at each of the plurality of depths and different time delays. A source response is removed from the seismic data using the far-field signatures of the seismic source.

Abstract: Method for correcting OBC or deep-towed seismic streamer data for surface-related multiple reflections. The measured pressure data, preferably after conditioning (71), are simulated using a forward model that includes a water propagation operator between source locations and receiver locations and a term representing primary impulse responses (72). Other terms include direct arrivals and source wavelets. Iterative optimization of an objective function is used to minimize the difference between measured and simulated data, updating the primary impulse response term and optionally the source wavelets term each iteration cycle (73). The converged primary impulses (74) are used to construct simulated multiples and direct arrivals (75), which can be subtracted from the measured data. Optionally the measured data might be blended during the forward simulation (72), to save computational costs in the forward simulation (72) and in the inversion (73).

Abstract: An apparatus and method for 3D seismic exploration for use in a small ship. The apparatus includes a seismic source towed by the small ship from a rear side thereof, a pair of support rods connected to the rear side and horizontally arranged in two rows behind the seismic source in the direction extending from a sailing direction of the ship, and a plurality of streamers arranged between the support rods in the sailing direction of the ship.

Abstract: There is a method of seismic data processing that includes receiving seismic data that includes a set of seismic traces, each trace including a signal recorded by a sensor after having been propagated in a subsurface area; migrating the seismic data according to a first velocity model; picking from the time-migrated seismic data one or more events corresponding to one or more subsurface reflectors so as to obtain a set of facets locally approximating the event; kinematic demigrating the picked set of facets so as to obtain simplified seismic data that includes the set of facets and a set of attributes associated with the set of facets; migrating the set of facets based on a second velocity model; and updating the initial velocity model based on an alignment of migrated points within the set of facets.

Abstract: A method of logging a perforation tunnel and associated features of the perforation tunnel can include the following features. A logging device including an ultrasonic transducer is located downhole into a well. The well has a casing. The ultrasonic transducer has a focal point that is a distance from the ultrasonic transducer so as to be behind the inner face of the casing. An ultrasonic signal is projected from the ultrasonic transducer. A reflection of the ultrasonic signal is reflected from an internal portion of the perforation tunnel, the perforation tunnel extending through the casing and into formation. A transit time is measured between transmission and reception of the ultrasonic signal. A position of the ultrasonic transducer corresponding to the ultrasonic transmission and reception of the reflected signal is determined.

Abstract: A method and system includes determining a subsurface fluid seismic attribute comprising recording a signal at a wellhead related to pumping fracture stimulation fluid to obtain a pressure pulse pump signal. A deconvolution operator is determined from the obtained pressure pulse pump signal. Seismic data are acquired from a plurality of sensors. Travel time differences are computed for the seismic data between the plurality of sensor locations and the subsurface position. Seismic data are deconvolved with the deconvolution operator to obtain a plurality of deconvolution coefficients associated with the subsurface position. The computed travel time differences are used to sum the plurality of deconvolution coefficients associated with the subsurface position to obtain a subsurface fluid seismic attribute at the subsurface position.

Abstract: An apparatus includes an array of seismic sensor units that are adapted to acquire measurements in connection with a land surface-based seismic survey. Each seismic sensor unit includes a particle motion sensor and a rotation sensor.

Abstract: The invention relates to a seismic acquisition process where multiple seismic sources are used to acquire seismic energy using encoding so that all of the sources may deliver seismic energy at the same time where the sweeps are arranged to be back to back with no listen time and wherein a pseudo listen time that is uncontaminated is created in the composite data record. After the listen time is created, the composite data may be source separated for further processing and analysis.

Abstract: Systems and methods for seismic data acquisition utilizing wireless modules to perform real time data read out. The wireless modules may be assigned a shared multiplexing sequence through which each module advances in successive transmission periods. Wireless modules belonging to a shared collision domain may be operated out of phase from one another with respect to the shared multiplexing signature sequence. As such, a dynamic multiplexing regime may be implemented. The shared multiplexing signature sequence may include, among others, a plurality of different frequencies, a plurality of different codes, or a plurality of different discrete time periods.

Abstract: The present invention concerns a hydrophone signal limiting shunt switch, electrically associated and physically conjoined with a conventional hydrophone, for limiting hydrophone signal operability to water depths less than a predetermined, proscribed depth. The primary components of the shunt switch are a protected plunging bolt, at least one disk spring and an electrically conducting foot, none of which are ever in direct contact with the ocean environment. Flexure of the disk spring is the sole determinant of switch actuation. Upon sensing a predetermined, proscribed operating depth, the protected plunging bolt forces the electrically conducting foot to shunt the electrical connection between the associated hydrophone and the hydrophone transmission cable, consequently, quenching the hydrophone signal at the proscribed depth.

Abstract: 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.

Abstract: Computational systems and methods to be carried out by the computational systems for determining streamer-depth bias during exploration-seismology experiments are disclosed. An exploration-seismology vessel tows a number of streamers that form a smoothly varying data acquisition surface located beneath a fluid surface. In one aspect of this disclosure, the method determines a set of image points that represent a profile of the fluid surface above each streamer. The image points are determined based on pressure and velocity wavefields measured at dual sensors of the streamer. The method then determines an elevation parameter of the image points that minimizes DC offset in a spectral domain of the image points. The elevation parameter corresponds to the streamer-depth bias and can be used to correct for the streamer-depth bias in subsequent calculations of a fluid-surface profile.

Abstract: A method for use in a land-based seismic survey includes: transmitting a plurality of source control commands to a plurality of seismic sources over a VHF/IP network; and managing congestion on the VHF/IP network while transmitting the source control commands. In other aspects, a program storage medium encoded with instructions that, when executed by a processor, perform such a method and a computer programmed to perform such a method.

Abstract: Described herein is a seismic streamer formed of sections including a main sheath covered with an external sheath, wherein said external sheath is formed using a thermoplastic material loaded with a biocide material.

Abstract: The invention relates to a process for two separate seismic crews to work in proximity to one another that would otherwise require expensive time sharing where one crew is a conventional seismic acquisition system and the other is a phase encoded seismic acquisition system. Typically, each recording system would receive seismic energy from the other that neither data set would be very useful. The invention primarily envisions some collaboration between the crews where each adjusts its sweeps to comprise a different time duration so that the energy the other crew's sources are distinguishable in the data set and easily eliminated therefrom. Distinctions may be further enhanced when the two crews use construct their sweeps so that each crew has a distinctly different start frequency and a distinctly different end frequency.

Abstract: Systems and methods for positioning one or more spread elements of a marine seismic spread are described. One system comprises a seismic vessel-mounted acoustic Doppler current meter adapted to ascertain at least the horizontal component of the current velocity vector at a point ahead of the seismic vessel, and one or more controllers adapted to use the ascertained current velocity vector to control position of one or more seismic spread elements. 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. 37 CFR 1.72(b).

Abstract: Methods and systems for processing microseismic waveforms. The methods and systems provide determining a measure of waveform fit in the frequency-domain comprising constructing, in the frequency-domain, at least one of an amplitude misfit functional and a cross phase functional between arrivals; and estimating source parameters and/or model parameters.

Abstract: One embodiment of the invention concerns a probe that couples to a seismic vessel via a tow cable. When deploying probes from a seismic vessel that is towing source arrays and streamers, the probe and its tow cable can tangle with elements of the towed seismic spread. However, a cable guide may be used to lessen the risk for such entanglement by guiding the tow cable into the water at a distance removed from the seismic spread. Also, the probe may be steerable to steer the probe and tow cable away from the seismic spread. Other embodiments are described herein.

Abstract: A technique includes obtaining a plurality of sets of measurements of distances between nodes located on a seismic spread element while the element is in tow. Each set is acquired in response to the operation of a different set of sources. The technique includes determining a three-dimensional structure of the seismic spread element while in tow based at least in part on the sets of measurements.

Abstract: A seismic information processing method and apparatus includes attenuating flexural wave noise information from seismic information. Flexural wave information removal includes receiving the seismic information using an information processing device interface, the seismic information having a plurality of directional components acquired using a multi-axis motion sensor coupled to ice floating on a body of water, the seismic information including desired seismic information and the flexural wave information. A noise model of the flexural wave information may be generated using at least one of the plurality of seismic information directional components using an information processing device. The noise model is improved using an adaptive correction filter, and the improved noise model is applied to at least one directional component of the received seismic information to attenuate the flexural wave information wave in the seismic information.