Abstract: A method of generating geophysical data using at least one source. The method may include the steps of generating a geophysical wavefield with a varying signature using at least one source, wherein the signature is varied in a periodic pattern.

Abstract: A method of generating geophysical data using at least one source. The method may include the steps of generating a geophysical wavefield with a varying signature using at least one source, wherein the signature is varied in a periodic pattern.

Abstract: A method of generating geophysical data using at least one source. The method may include the steps of generating a geophysical wavefield with a varying signature using at least one source, wherein the signature is varied in a periodic pattern.

Abstract: A method of generating geophysical data using at least one source. The method may include the steps of generating a geophysical wavefield with a varying signature using at least one source, wherein the signature is varied in a periodic pattern.

Abstract: A method and system for determining at least one property associated with a selected axis of a manipulator (2). The elasticity of the links (4, 6, 9, 10, 13, 14) and joints (3, 5, 7, 8, 11, 12) of a manipulator (2) can be modeled and the resulting compliance can be determined. A certain method is used to control the manipulator (2) such that certain quantities related to actuator torque and/or joint position can be determined for a certain kinematic configuration of the manipulator (2). Depending on the complexity of the manipulator (2) and the number of properties that are of interest, the manipulator (2) is controlled to a plurality of different kinematic configurations in which configurations the quantities are determined. Thereafter, a stiffness matrix (K) for each component of the manipulator (2) can be determined, and a global stiffness matrix (MSM) for the total manipulator (2) can be determined in order to determine at least one property of the selected axis.

Abstract: A method and system for determining at least one property associated with a selected axis of a manipulator (2). The elasticity of the links (4, 6, 9, 10, 13, 14) and joints (3, 5, 7, 8, 11, 12) of a manipulator (2) can be modeled and the resulting compliance can be determined. A certain method is used to control the manipulator (2) such that certain quantities related to actuator torque and/or joint position can be determined for a certain kinematic configuration of the manipulator (2). Depending on the complexity of the manipulator (2) and the number of properties that are of interest, the manipulator (2) is controlled to a plurality of different kinematic configurations in which configurations the quantities are determined. Thereafter, a stiffness matrix (K) for each component of the manipulator (2) can be determined, and a global stiffness matrix (MSM) for the total manipulator (2) can be determined in order to determine at least one property of the selected axis.

Abstract: A method of processing seismic data acquired consequent to actuation of a seismic source is described. The method comprises taking the result of the following process into account when processing the seismic data where the process comprises estimating the effect of uncertainty in the position and/or orientation of the seismic source relative to the measuring receiver on processing the seismic data by estimating a source wavefield from data acquired by a near-field measuring receiver and from a first parameter set including at least one parameter indicative of the position and/or orientation of the seismic source relative to the measuring receiver, varying the value of at least one parameter of the first parameter set, estimating the source wavefield from the data acquired by the measuring receiver and from the varied first parameter set and obtaining information about the uncertainty in the estimate of the source wavefield.

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: 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.

Abstract: Described are methods for obtaining seismic signals representative of properties of the earth's interior, including the steps of obtaining near-field acoustic signals recorded in the vicinity of a seismic source (13), muting from the near-field acoustic signals at least partly signals representing direct arrivals from the seismic source (13), and using a remaining part of the obtained signals as estimate of a zero-offset data set. The zero-off set data set can then be used to interpolate data from conventional acquisition location, such as streamers (11), to locations closer to the source (13).

Abstract: 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.

Abstract: The present invention relates to a method of processing data representing energy propagating through a medium (e.g., acoustic, elastic or electromagnetic energy) and describes an efficient and flexible approach to forward modeling and inversion of such energy for a given medium. The representation theorem for the wave-equation is used, in combination with time-reversal invariance and reciprocity, to express the Green's function between two points in the interior of the model as an integral over the response in those points due to sources regularly distributed on a surface surrounding the medium and the points.

Abstract: 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.

Abstract: 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.

Abstract: The method presented accounts for three-dimensional effects when deghosting marine seismic data. The method relies on having second-order spatial derivatives in the cross-line direction available. The second-order cross-line derivative can be estimated directly or through indirect measurements of other wavefield quantities and by using wave-equation techniques to compute the desired term. The method preferably employs either a multicomponent streamer towed in the vicinity of the sea surface, a twin-streamer configuration near the sea-surface, or a configuration of three streamers that are separated either vertically or horizontally to estimate the second-order vertical derivative of pressure.

Abstract: 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.

Abstract: 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.

Abstract: A method of processing seismic data acquired consequent to actuation of a seismic source is described. The method comprises taking the result of the following process into account when processing the seismic data where the process comprises estimating the effect of uncertainty in the position and/or orientation of the seismic source relative to the measuring receiver on processing the seismic data by estimating a source wavefield from data acquired by a near-field measuring receiver and from a first parameter set including at least one parameter indicative of the position and/or orientation of the seismic source relative to the measuring receiver, varying the value of at least one parameter of the first parameter set, estimating the source wavefield from the data acquired by the measuring receiver and from the varied first parameter set and obtaining information about the uncertainty in the estimate of the source wavefield.

Abstract: A method of monitoring a marine seismic source array comprises, consequent to actuation of a seismic source array (14), making a near-field measurement of seismic energy emitted by the seismic source array (14), using at least one near field sensor (15) and also acquiring seismic data using at least one seismic receiver (18). The far-field signature of the source array at one or more of the receiver location(s) is estimated from the near-field measurements of the emitted seismic energy, and this is compared with seismic data acquired at the receiver(s). This provides an indication of whether the source array and the method for predicting far-field signatures are operating correctly.

Abstract: A method and apparatus implementing a technique for mitigating noise in seismic data are presented. The technique includes estimating a noise component in a set of multicomponent seismic data representing a recorded wavefield from the relationship at the free surface of an upgoing component and a downgoing component decomposed from the recorded wavefield; and removing the estimated noise component from the seismic data. The noise component can be estimated by decomposing a recorded wavefield into an upgoing component and a downgoing component and isolating a noise component in the recorded wavefield from the relationship of the decomposed upgoing and downgoing components at the free surface.