Abstract: Methods and apparatus are provided for generating velocity models for pre-stack depth migration (“PSDM”). Seismic, gravity and electromagnetic joint inversion input data are generated based on observed seismic, gravity and electromagnetic data (e.g., magnetotelluric and/or controlled source electromagnetic), and velocity, density and resistivity models. A joint inversion is performed to produce a multiparametric model that is a function of velocity, density and resistivity parameter distributions. The separate parameter distributions are extracted from the multiparametric model, and the extracted velocity model is used to perform a PSDM. A migration velocity analysis is performed on PSDM output to generate seismic image residuals. If the seismic image residuals meet predetermined quality objectives, the extracted velocity model is output as the final velocity model for PSDM.

Abstract: Systems and methods for automatic steering of marine seismic sources are described. One system comprises a marine seismic spread comprising a towing vessel and a seismic source, the seismic source comprising one or more source arrays each having a center of source array, each source array having one or more source strings; a seismic source deployment sub-system on the towing vessel, the sub-system controlled by a controller including a software module, the software module and the deployment sub-system adapted to control an inline distance between one of the centers of source array and a target coordinate. It is emphasized that this abstract is provided to comply with the rules requiring an abstract, allowing 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.

Abstract: Method for processing seismic data. In one implementation, the method includes converting a common midpoint (CMP) gather of seismograms into one or more interferogram common midpoint (ICMP) gathers, generating a semblance spectrum for each ICMP gather, stacking the semblance spectrum from each ICMP gather to generate a combined semblance spectrum and deriving a normal moveout (NMO) velocity profile from the combined semblance spectrum.

Abstract: A method of determining an orientation of a data acquisition system deployed on a seafloor includes measuring horizontal magnetic fields using detectors on the data acquisition system while the data acquisition rotates and descends to the seafloor or rises from the seafloor. Resting horizontal magnetic fields are measured after the data acquisition system is on the seafloor. A heading of the data acquisition system on the seafloor may be determined based on maximum and minimum horizontal magnetic fields measured during the descent and the resting horizontal magnetic fields.

Abstract: The present invention provides a method for pre-stack combining of over/under seismic data. The method includes determining a calibration filter using a first pre-stack marine seismic data set acquired at a first depth and a second pre-stack marine seismic data set acquired at a second depth, wherein the second depth is greater than the first depth and determining a third data set based upon the first pre-stack marine seismic data set, the second pre-stack marine seismic data set, and the calibration filter.

Abstract: A method and apparatus for predicting a plurality of surface multiples for a plurality of target traces in a record of seismic data. In one embodiment, the method includes creating a file containing information regarding a plurality of pairs of recorded traces. Each pair of recorded traces is substantially closest to a desired shot-side trace and a desired receiver-side trace. The method further includes convolving the pairs of recorded traces to generate a plurality of convolutions and stacking the convolutions for each target trace.

Abstract: Seabed sensor units, systems including same, and methods for acquiring seabed data are described, one seabed sensor unit comprising a base, the base containing at least one sensor able to detect a seismic signal, electronics comprising a clock and one or more electronic components enabling the sensor to communicate seismic data to one or more memory modules, and a local autonomous power source. 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: A method includes: interpolating a set of crossline seismic data from a set of acquired multicomponent seismic data; predicting a multiple in the interpolated and acquired seismic data from the combined interpolated and acquired multicomponent seismic data; and suppressing the predicted multiple. Other aspects include a program storage medium encoded with instructions that, when executed by a computing device, perform such a method and a computing apparatus programmed to perform such a method.

Abstract: A method of processing seismic data comprises processing data representative of the acceleration wavefield so as to obtain information about the earth's subsurface direct from the seismic data representative of the acceleration wavefield. In conventional techniques for processing seismic data representative of the acceleration wavefield the data are transformed to the velocity domain at an early stage in the processing. The invention enables the transform step to be eliminated, thereby simplifying the processing and eliminating the risk that the transform might degrade the data. Furthermore, the increased sensitivity at high frequencies of a typical acceleration sensor compensates for the low-pass filter effect of the earth.

Abstract: A method for use in seismic surveying includes determining the shape of a seismic cable during a seismic survey; determining the tension on the seismic cable at a plurality of points along the seismic cable; and predicting a current that will impact the seismic cable from the determined shape and the determined tension. The method may be practiced two-dimensionally in the context of a marine survey employing a towed streamer array or three-dimensionally in the context of laying an array of ocean bottom cables on the seabed. The predicted currents can, in some embodiments, be used to make steering corrections for the seismic cables.

Abstract: A housing for a seismic sensing element (3) for use on the earth's surface comprises connecting means (5) for connecting the housing (3) to a support cable (2) so as to allow relative movement between the sensor housing (3) and the cable (2). This de-couples the sensor housing from the support cable, and improves the fidelity of the sensor. The connecting means (5) preferably comprises resilient connecting elements, to prevent the transmission of vibrations between the support cable and the sensor housing. The sensor housing (3) preferably has a flat base (1), so that there is good coupling between the sensor housing and the earth. Alternatively, the sensor housing can be fitted with a base member ((24a, 24b, 24c) that has at least one flat face (26, 26a, 26b, 26c).

Abstract: Method for identifying one or more fracture clusters in an area of interest. In one implementation, the method may include determining a first inclination of each fracture cluster using borehole data. The first inclination refers to a first average angle with respect to horizontal. The method may further include extracting a first set of fracture clusters from seismic data using a filter based on the first inclination and a strike azimuth of each fracture cluster.

Abstract: A method of acquiring or processing multi-component seismic data obtained from seismic signals propagating in a medium, the method comprising the steps of: selecting a first portion of the seismic data in which the first arrival contains only upwardly propagating seismic energy above the seafloor; and determining a first calibration filter from the first portion of the seismic data, the first calibration filter being to calibrate a first component of the seismic data relative to a second component of the seismic data.

Abstract: A method of determining a vertical component of particle velocity from seismic data acquired using at least one receiver disposed within a water column includes determining the vertical component of particle velocity from the pressure at a first location and a second location. The first location is the location of a first receiver, and is vertically beneath the second location. The method uses an operator accurate for seismic data acquired at a vertical separation between the first and second locations of up to at least 0.4 times the minimum wavelength of seismic energy used to acquire the seismic data. The second location may be at or above the surface of the water column. Alternatively, the method may be applied to a twin streamer seismic surveying arrangement in which the second location is below the surface of the water column and is the location of a second receiver.

Abstract: Methods for generating a time lapse difference image. In one implementation, the method includes estimating a trace in a first seismic survey data set at each trace coordinate of a second seismic survey data set, estimating a trace in the second seismic survey data set at each trace coordinate of the first seismic survey data set and calculating trace differences between the first seismic survey data set and the second seismic survey data set at each trace coordinate of the first seismic survey data set and the second seismic survey data set.

Abstract: A method and apparatus for synchronizing a real time clock of a slave computer with a real time clock of a master computer. The method includes the steps of: calculating a first time drift value between the real time clock of the slave computer and the real time clock of the master computer, calculating a second time drift value between the real time clock of the slave computer and the real time clock of the master computer, calculating an average time drift value between the real time clock of the slave computer and the real time clock of the master computer using the first time drift value and the second time drift value, and adjusting the real time clock of the slave computer using the average time drift value.

Abstract: Methods are described for actively steering a towed marine seismic component using one or more actively controllable control members; reducing the actively steering of the control members during duration of a time window of recording seismic reflections from a sub-surface geological feature of interest; and resuming the actively steering of the control members after the time window. The marine seismic component may be a streamer, a source, or both. Other methods allow measuring initial orientation of a streamer based on measuring static control surface angle of a control surface of an inline steerable bird. This abstract is provided to comply with the rules requiring an abstract, and allow a reader to ascertain the subject matter of the technical disclosure. It will not be used to interpret or limit the scope or meaning of the claims.

Abstract: It is described a method for spatially filtering 3D seabed seismic data acquired in a cross-line geometry including methods of how to decompose the data using a filter with two spatial components.

Abstract: Apparatus and methods are described for remotely controlling position of marine seismic equipment. One apparatus comprises a source connected to a tow member; and an adjustment mechanism connected to the source and the tow member, the adjustment mechanism adapted to actively manipulate an angle of attack of the source. 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.

Abstract: Implementations of various techniques for a seismic inversion method. In one implementation, the method may include estimating a wavelet of a recorded seismic trace at a well location, transforming the recorded seismic trace to a relative seismic impedance trace, estimating a low frequency model trace using the relative seismic impedance trace and adding the low frequency model trace to the relative seismic impedance trace to generate an absolute trace.