Abstract: A method of calculating a seismic noise image for a formation comprises the steps of: a) obtaining data representing a multicomponent seismic signal from at least one receiver, in response to transmitting seismic waves into the formation; b) obtaining a velocity model of the earth formation; c) determining a plurality of wave field components; d) obtaining a set of second components; e) obtaining, for each subsurface point, at least two products, each product comprising the product of a selected wave field component and a different second component; and f) and generating a noise image by calculating at least one difference between different products for at least one image point.

Abstract: A method of processing data obtained from seismic prospecting of an earth formation, comprises obtaining data representing a multicomponent seismic signal from a multicomponent seismic receiver at a receiver location in an earth formation, in response to transmitting seismic waves into the earth formation; performing a wave-equation migration of the multicomponent seismic signal to obtain a seismic image of the earth formation, wherein the polarization of the seismic wave at the receiver location is taken into account and wherein a seismic image value at a point in the earth formation is calculated from a sum of products of a source field component for a particular dimension and a complex conjugated back propagated wave field component for the same dimension, summed over a plurality of dimensions.

Abstract: A method of calculating a seismic noise image for a formation comprises the steps of: a) obtaining data representing a multicomponent seismic signal from at least one receiver, in response to transmitting seismic waves into the formation; b) obtaining a velocity model of the earth formation; c) determining a plurality of wave field components; d) obtaining a set of second components; e) obtaining, for each subsurface point, at least two products, each product comprising the product of a selected wave field component and a different second component; and f) and generating a noise image by calculating at least one difference between different products for at least one image point.

Abstract: A method of processing data obtained from seismic prospecting of an earth formation, comprises obtaining data representing a multicomponent seismic signal from a multicomponent seismic receiver at a receiver location in an earth formation, in response to transmitting seismic waves into the earth formation; performing a wave-equation migration of the multicomponent seismic signal to obtain a seismic image of the earth formation, wherein the polarization of the seismic wave at the receiver location is taken into account and wherein a seismic image value at a point in the earth formation is calculated from a sum of products of a source field component for a particular dimension and a complex conjugated back propagated wave field component for the same dimension, summed over a plurality of dimensions.

Abstract: A method for providing a velocity profile for a subsurface region that includes the reflective interfaces, the method comprising the steps of: providing a set of data comprising signals transmitted by a transmitter and collected at a receiver, wherein the data include a primary signal that has been reflected off of one of the reflective interfaces and a multiply-reflected signal that has been reflected off of at least two of the reflective interfaces, providing a velocity model for the subsurface region, using the velocity model and the primary signal to construct a first image of the subsurface region, using the velocity model and the multiply-reflected signal to construct a second image of the subsurface region, determining a measure of match between the first and second images, adjusting the velocity model based on this measure, and repeating the steps until the measure of match attains a desired level.

Abstract: A method for providing a velocity profile for a subsurface region that includes the reflective interfaces, the method comprising the steps of: providing a set of data comprising signals transmitted by a transmitter and collected at a receiver, wherein the data include a primary signal that has been reflected off of one of the reflective interfaces and a multiply-reflected signal that has been reflected off of at least two of the reflective interfaces, providing a velocity model for the subsurface region, using the velocity model and the primary signal to construct a first image of the subsurface region, using the velocity model and the multiply-reflected signal to construct a second image of the subsurface region, determining a measure of match between the first and second images, adjusting the velocity model based on this measure, and repeating the steps until the measure of match attains a desired level.

Abstract: Method of removing irregularities caused by tube waves from seismic data obtained in a borehole seismic survey, using a set of seismic or sources and a set of seismic receivers each arranged in a borehole, in which seismic data is time shifted based on an estimated tube wave velocity, filtered and then the time shift is reversed and applied to the original data set resulting in a corrected set, which is again time shifted opposite to the original time shift to remove and identify tube wave irregularities.

Abstract: Method of removing irregularities caused by tube waves from seismic data obtained in a borehole seismic survey, which method comprises the steps of (a) obtaining a set of original seismic data; (b) subjecting the original seismic data set to a time-shift based on an estimated tube wave velocity to align the tube waves in time; (c) applying a structurally oriented, edge-preserving filter to the time-shifted seismic data set; (d) undoing the time shift for the time-shifted, predicted tube wave data set; (e) subtracting the predicted tube wave data set from the original seismic data set; (f) subjecting the set of corrected, original seismic data to a time-shift based on a tube wave velocity opposite to the velocity used in step (b); and (g) repeating steps (c), (d) and (e).

Abstract: A method for creating an image of an underground formation around a borehole. An omnidirectional seismic source is activated in the borehole and a three-component receiver records the components of the reflected energy from the formation. The direction or ray of the returned energy is computed as a function of the two-way travel time A position in the formation is selected as a potential formation reflection point compared with the directional ray and two-way travel time. Where the directional ray and two-way travel time substantially correspond to the selected point, the data is attributed to the selected point The process continues with the selection of additional points and calculation of attributed return energy direction and two-way travel time to such points to comprise a set of reflectors which form the image of the formation.