Abstract: A method includes receiving seismic data of a seismic survey; defining a two-dimensional domain in dimensions x and y; identifying a target trace (S, R) of the seismic survey where S represents a source at (xs, ys) and where R represents a receiver at (XR, yR); defining with respect to the two-dimensional domain, a source trace (S, X1) as a primary trace, a receiver trace (R, X2) as a primary trace, and a generator trace (X1, X2) as associated with an interbed multiple generator; convolving the primary traces and crosscorrelating with the generator trace for a plurality of different (X1, X2) pairs where each of the plurality of (X1, X2) pairs defines a line segment where the line segments are substantially parallel to one another; and, based at least in part on the convolving the primary traces and crosscorrelating with the generator trace, generating seismic data with attenuated multiple energy.

Abstract: A method includes receiving seismic data of a seismic survey; defining a two-dimensional domain in dimensions x and y; identifying a target trace (S, R) of the seismic survey where S represents a source at (xs, ys) and where R represents a receiver at (XR, yR); defining with respect to the two-dimensional domain, a source trace (S, X1) as a primary trace, a receiver trace (R, X2) as a primary trace, and a generator trace (X1, X2) as associated with an interbed multiple generator; convolving the primary traces and crosscorrelating with the generator trace for a plurality of different (X1, X2) pairs where each of the plurality of (X1, X2) pairs defines a line segment where the line segments are substantially parallel to one another; and, based at least in part on the convolving the primary traces and crosscorrelating with the generator trace, generating seismic data with attenuated multiple energy.

Abstract: Synthetic survey data is generated using a two-way or one-way wave propagator based on a current model of a target structure. The current model is modified to reduce a difference between the synthetic survey data and observed survey data, while maintaining unchanged a velocity component of the current model, where the modifying of the current model produces a modified model. The modified model is used to reduce an adverse effect of multiples in the target structure, or to promote a favorable effect of multiples in the target structure.

Abstract: A method includes receiving a seismic dataset from a survey, wherein the seismic dataset represents a portion of a subsurface geological formation and includes primary and multiple data. The method further includes the steps of conditioning the seismic dataset and estimating a model of the multiple data in the conditioned seismic dataset based on a user-defined parameter to derive a primary data set. Further, the method includes the steps of computing a velocity model from the primary data set using the user-defined parameter and updating the estimated multiple model based at least on a modification of the user-defined parameter. In addition, the method includes the steps of recomputing the primary data and the velocity model based on the modified user-defined parameter and generating an image of the primary data.

Abstract: A technique generates seismic data that may be analyzed. A combination sensor is operated and deployed in a borehole to obtain orientation data, such as data related to the local magnetic field and a log of the magnetic field direction in the borehole. Following the combination sensor, at least one multi-component seismic source is deployed downhole into the borehole. The at least one multi-component seismic source comprises sensors, such as an inclinometer and a magnetometer. Data from the combination sensor and from the at least one multi-component seismic source is processed to determine an absolute orientation of the at least one multi-component seismic source.

Abstract: One embodiment of the present disclosure includes a method for processing seismic data comprising the steps of receiving data representing seismic energy gathered from a formation by a plurality of seismic receivers, wherein the data include primary and multiple data. A copy of the received data is created and compensated to reduce amplitude attenuation effects due to transmission and absorption losses. A multiple prediction algorithm is applied to the received and compensated data to obtain a multiple data prediction. The multiple data prediction is subtracted from the received data to obtain primary data. The primary data is processed to reduce attenuation effects in the received data.

Abstract: A well-logging tool includes a magnetic field logging tool and a borehole seismic array, which includes a plurality of seismic sensor devices coupled together in series. Each seismic sensor device includes a sensor housing and at least one seismic sensor carried by the sensor housing. A magnetometer is carried by the sensor housing to sense the local magnetic field. A controller cooperates with the magnetic field logging tool to generate a log of the local magnetic field relative to the true earth geographic pole. The controller cooperates with the borehole seismic array to determine an orientation of each seismic sensor device based upon the respective sensed local magnetic field and log of the local magnetic field relative to the earth geographic pole.

Abstract: A tool is described for seismic data collection which may have sensors mounted along its entire length to sample both geophysical signal and noise including at least one of acoustic noise, system noise, and noise resulting from the interaction between the two. Systems and methods for acquiring borehole seismic data are also described. In contrast to conventional systems which attempt to avoid introducing noise into the collected data stream, the present systems include a sufficient type, number, and spacing of sensors to intentionally sample at least one source of noise. The methods include operating a borehole seismic acquisition system to sample both a target signal and at least one source of noise and using a processor with machine-readable instructions for separating the noise from the signal.

Abstract: Synthetic survey data is generated using a two-way or one-way wave propagator based on a current model of a target structure. The current model is modified to reduce a difference between the synthetic survey data and observed survey data, while maintaining unchanged a velocity component of the current model, where the modifying of the current model produces a modified model. The modified model is used to reduce an adverse effect of multiples in the target structure, or to promote a favorable effect of multiples in the target structure.

Abstract: A method includes receiving a seismic dataset from a survey, wherein the seismic dataset represents a portion of a subsurface geological formation and includes primary and multiple data. The method further includes the steps of conditioning the seismic dataset and estimating a model of the multiple data in the conditioned seismic dataset based on a user-defined parameter to derive a primary data set. Further, the method includes the steps of computing a velocity model from the primary data set using the user-defined parameter and updating the estimated multiple model based at least on a modification of the user-defined parameter. In addition, the method includes the steps of recomputing the primary data and the velocity model based on the modified user-defined parameter and generating an image of the primary data.

Abstract: A technique includes determining at least one attribute of a slowness vector associated with a seismic gather based on pressure data and an indication of particle motion that is measured by at least one seismic sensor while in tow.

Abstract: One embodiment of the present disclosure includes a method for processing seismic data comprising the steps of receiving data representing seismic energy gathered from a formation by a plurality of seismic receivers, wherein the data include primary and multiple data. A copy of the received data is created and compensated to reduce amplitude attenuation effects due to transmission and absorption losses. A multiple prediction algorithm is applied to the received and compensated data to obtain a multiple data prediction. The multiple data prediction is subtracted from the received data to obtain primary data. The primary data is processed to reduce attenuation effects in the received data.

Abstract: The disclosure provides a borehole tool for seismic data collection. The tool comprises a cable to be positioned within a borehole and at least one sensor for measuring seismic signals mounted on the cable. The sensors provide measurements of particle motion (velocity or acceleration) perpendicular to an axis of the borehole. The disclosure also provides methods of seismic surveying, which involves positioning the tool in the borehole, firing a seismic source generating a seismic wave and measuring particle motion associated with the passing seismic wave perpendicular to an axis of the borehole using the at least one sensor for measuring particle motion.

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 generates seismic data that may be analyzed. A combination sensor is operated and deployed in a borehole to obtain orientation data, such as data related to the local magnetic field and a log of the magnetic field direction in the borehole. Following the combination sensor, at least one multi-component seismic source is deployed downhole into the borehole. The at least one multi-component seismic source comprises sensors, such as an inclinometer and a magnetometer. Data from the combination sensor and from the at least one multi-component seismic source is processed to determine an absolute orientation of the at least one multi-component seismic source.

Abstract: An embodiment of the invention relates to a method of processing seismic data comprising a plurality of traces, each trace having a source position, a receiver position and a midpoint position, each having coordinates in an inline direction and a crossline direction. The invention uses a data set comprising traces having one of the source position, the receiver position or the midpoint position having coordinates which are invariant in one of the inline or the crossline directions. A non-iterative surface related multiple attenuation algorithm is applied to the data set which assumes substantial non-variation of depth of reflectors in the same one of the inline or the crossline directions.

Abstract: A well-logging tool includes a magnetic field logging tool and a borehole seismic array, which includes a plurality of seismic sensor devices coupled together in series. Each seismic sensor device includes a sensor housing and at least one seismic sensor carried by the sensor housing. A magnetometer is carried by the sensor housing to sense the local magnetic field. A controller cooperates with the magnetic field logging tool to generate a log of the local magnetic field relative to the true earth geographic pole. The controller cooperates with the borehole seismic array to determine an orientation of each seismic sensor device based upon the respective sensed local magnetic field and log of the local magnetic field relative to the earth geographic pole.

Abstract: Systems and methods for seismic processing are provided. For example, the method may include modeling seismic data as a combination of a modeling matrix and a parameter vector, and determining a plurality of solution spaces of filter models for the parameter vector. The method may also include calculating data residual terms for the filter models, wherein the data residual terms are related to a difference between the seismic data and a combination of the modeling matrix and the parameter vector determined using the filter models. The method may further include selecting a solution filter model for the parameter vector from among the filter models based on a combination of the data residual terms and complexities of the filter models, and performing a seismic processing operation using the solution filter model and the seismic data.

Abstract: Neutrally-buoyant tools for seismic data collection are provided that may range from several hundred meters to several kilometers in length and have integrated sensors which move along with the borehole fluid in response to a passing seismic wave. The disclosure also provides methods of deploying neutrally-buoyant tools, which includes using a tractor, adding a weight or both to the tool in order to overcome the difficulty of lowering a neutrally buoyant tool into a borehole, and optionally occasionally clamping the tool to the borehole to alleviate tension in the tool. This disclosure also provides methods of acquiring seismic data, which involves positioning a neutrally-buoyant tool in a borehole such that the tool is able to move relatively freely along with the borehole fluid in response to a seismic wave passing through the fluid, firing a seismic source, and using the sensors to collect seismic data generated thereby.

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).