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: 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: The disclosure provides neutrally-buoyant tools for seismic data collection. The tools 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: 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: A technique includes towing a spread of at least one streamer to acquire seismic data in response to energy produced by a seismic source. The technique includes towing the seismic source at least 100 meters behind a front end of the spread to configure the spread to acquire a split spread gather record.

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: This invention relates to well logging instrumentation, specifically, to measuring devices which use an advanced slip-free borehole contact interaction mechanism. A measuring probe for an oil and gas wells and/or casings includes a main body and at least one robotic arm, fixed to the main body and provided with a polygonal rotating contact tip at the arm's free end. The measuring probe is used as a measuring device and provides a successive slip-free continuous contact between the rotating surface of the tip and the inner wall of the oil & gas wells and/or casings. The tip is furnished with at least one sensor that picks up the geological formations response to a signal emitted directly to the geological formation via the points of contact.

Abstract: A technique includes towing a spread of at least one streamer to acquire seismic data in response to energy produced by a seismic source. The technique includes towing the seismic source at least 100 meters behind a front end of the spread to configure the spread to acquire a split spread gather record.

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 method is described for reducing multiples in marine seismic data using at least two sets of signals representing seismic energy reflected and/or refracted from an earth structure using a plurality of seismic receivers located in a body of water with the two sets differing in the traveltime of signals through the body of water, separating said signals into up- and down-going wavefields and combining the two sets to remove multiples.

Abstract: Method for computing one or more timing errors that occur in one or more multiples predicted by a multiple prediction algorithm. The method includes the steps of generating one or more actual three-dimensional primary travel times and one or more actual three-dimensional multiple travel times, applying the multiple prediction algorithm to the actual three-dimensional primary travel times to generate one or more travel times for the multiples predicted by the multiple prediction algorithm, and subtracting the actual three-dimensional multiple travel times from the travel times for the multiples predicted by the multiple prediction algorithm.

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: A technique includes obtaining seismic data indicative of measurements acquired by seismic sensors of a composite seismic signal produced by the firings of multiple seismic sources. The technique includes associating models that describe geology associated with the composite seismic signal with linear operators and characterizing the seismic data as a function of the models and the associated linear operators. The technique includes simultaneously determining the models based on the function and based on the determined models, generating datasets. Each dataset is indicative of a component of the composite seismic signal and is attributable to a different one of the seismic sources.

Abstract: In a first aspect, a method for use in a time lapse, marine seismic survey includes accessing a set of baseline seismic data; accessing a set of acquired, time lapse seismic data; and interpolating a set of time lapse seismic data from the baseline seismic data and the acquired time lapse seismic data, at least one of the baseline seismic data and the acquired time lapse seismic data being multicomponent 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: 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: In a first aspect, a method for use in a time lapse, marine seismic survey includes accessing a set of baseline seismic data; accessing a set of acquired, time lapse seismic data; and interpolating a set of time lapse seismic data from the baseline seismic data and the acquired time lapse seismic data, at least one of the baseline seismic data and the acquired time lapse seismic data being multicomponent 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 present invention provides a method and apparatus for marine seismic data acquisition. The method may include determining a seismic source signature based on a pressure wave field and at least one component of particle motion measured by at least one seismic sensor while in tow.

Abstract: A method is described for reducing multiples in marine seismic data using at least two sets of signals representing seismic energy reflected and/or refracted from an earth structure using a plurality of seismic receivers located in a body of water with the two sets differing in the traveltime of signals through the body of water, separating said signals into up- and down-going wavefields and combining the two sets to remove multiples.

Abstract: Method for computing one or more timing errors that occur in one or more multiples predicted by a multiple prediction algorithm. The method includes the steps of generating one or more actual three-dimensional primary travel times and one or more actual three-dimensional multiple travel times, applying the multiple prediction algorithm to the actual three-dimensional primary travel times to generate one or more travel times for the multiples predicted by the multiple prediction algorithm, and subtracting the actual three-dimensional multiple travel times from the travel times for the multiples predicted by the multiple prediction algorithm.