Abstract: A survey method includes towing one or more sources and one or more streamers behind a vessel to acquire geophysical survey data. Steering signals are determined for at least one of: the one or more sources, the one or more streamers, and the vessel. The steering signals minimize an error function having parameters that include a measure of a cross-line position error and a measure of data quality. The cross-line position error may be measured as an offset of the sources or the receivers from their desired paths, or in some embodiments as an offset between midpoints for base survey traces and subsequent survey traces. Some embodiments may employ a maximum spatial cross-correlation coefficient between a newly acquired trace and one or more base survey traces as a data quality measure, while others may employ a time shift, a phase rotation, or a normalized root mean square error. Data quality may indicate sensor noise levels.

Abstract: A method for determining geodetic position of at least one point on a geophysical sensor streamer towed by a vessel in a body of water includes determining geodetic positions of a plurality of locations along a first geophysical sensor streamer towed at a first depth in the body of water. A lateral offset is caused between the first geophysical sensor streamer and a second geophysical sensor streamer towed at a second depth in the body of water. A distance is measured between at least two selected points along the first geophysical sensor streamer and a selected point along the second geophysical sensor streamer. A depth is measured at at least one point along the second geophysical sensor streamer. A geodetic position is determined at a selected point along the second geophysical sensor using the depth measurement, a direction of the lateral offset and the measured distances.

Abstract: A survey method includes towing one or more sources and one or more streamers behind a vessel to acquire geophysical survey data. Steering signals are determined for at least one of: the one or more sources, the one or more streamers, and the vessel. The steering signals minimize an error function having parameters that include a measure of a cross-line position error and a measure of data quality. The cross-line position error may be measured as an offset of the sources or the receivers from their desired paths, or in some embodiments as an offset between midpoints for base survey traces and subsequent survey traces. Some embodiments may employ a maximum spatial cross-correlation coefficient between a newly acquired trace and one or more base survey traces as a data quality measure, while others may employ a time shift, a phase rotation, or a normalized root mean square error. Data quality may indicate sensor noise levels.

Abstract: The geodetic position of a point on a streamer towed by a vessel in a body of water may be determined. Geodetic positions of a plurality positions along at least two of a plurality streamers towed in the body of water may be determined. Positions may be selected from the plurality of positions. Distances between pairs of the selected positions and between each of the selected positions and the point may be determined. Geodetic position of the point may be determined using the geodetic positions and distances.

Abstract: A lateral force and depth control device for a marine streamer includes a housing configured to be coupled within the streamer. A control surface is mounted to the housing such that a rotary orientation and an angle of attack of the control surface with respect to the housing are changeable. The device includes means for moving the control surface to a selected rotary orientation with respect to the housing. The device includes means for moving the control surface to a selected angle of attack with respect to the housing. A removable coupling is provided to couple the control surface to the means for moving to a selected rotary orientation and means for moving to a selected angle of attack.

Abstract: A method for determining positions of geophysical sensor streamers includes towing laterally spaced apart streamers maintained in relative relationship therebetween by paravanes proximate their forward ends. The streamers include spaced apart acoustic transmitters and acoustic receivers. The paravanes each include an acoustic transmitter or receiver. Signals are sent from the acoustic transmitters and are received at the acoustic receivers. Geodetic position signals are detected at each paravane. The identities of the transmitters of the received acoustic signals are determined to determine travel times of the received acoustic signals. The travel times are converted to distances between the identified transmitters and the receivers. Relative positions of the streamers are determined from the distances. The relative positions of the streamers are combined with the detected geodetic position signals to determine geodetic positions of the streamers.

Abstract: A lateral force and depth control device for a marine streamer includes a housing configured to be coupled within the streamer. A control surface is mounted to the housing such that a rotary orientation and an angle of attack of the control surface with respect to the housing are changeable. The device includes means for moving the control surface to a selected rotary orientation with respect to the housing. The device includes means for moving the control surface to a selected angle of attack with respect to the housing. A removable coupling is provided to couple the control surface to the means for moving to a selected rotary orientation and means for moving to a selected angle of attack.

Abstract: A lateral force and depth control device for a seismic streamer includes an inner housing including a coupling at each longitudinal end thereof. The couplings are configured to mate with a corresponding coupling at a longitudinal end of a streamer segment. The device includes an outer housing rotatably supported on the inner housing. A signal communication device is configured to transfer at least one of electrical power and signals between the inner housing and the outer housing while enabling relative rotation therebetween. A plurality of control surfaces are rotatably coupled to the outer housing and arranged about the circumference of the outer housing. The control surfaces are coupled to the outer housing by releasable couplings. A first controllable actuator and a second controllable actuator are disposed in the outer housing and functionally coupled to at least a first and a second one of the control surfaces, respectively.

Abstract: A system comprises a plurality of acoustic transmitters, mounted inside the streamers, adapted to transmit broadband signals having low cross-correlation between the signals of different transmitters; a plurality of acoustic receivers, mounted inside the streamers, adapted to receive the signals from the transmitters; at least one processor adapted to cross-correlate the signals received at the receivers with copies of transmitter signals to determine identities of the transmitters of the received signals and to determine travel times of the received signals; and a main processor adapted to convert the travel times to distances between the identified transmitters and the receivers and to determine relative positions of the streamers from the distances.

Abstract: Methods of processing neuronal signals include processing microelectrode recordings (MERs) or portions of MERs to provide arrays of associated values, such as estimates of power spectral density, or a marginal probability distribution, or a rate of change of a spike rate. Such arrays of values can be displayed, and a classifier can be applied to, for example, aid in associating a MER with a particular brain feature.

Abstract: A system comprises a plurality of acoustic transmitters, mounted inside the streamers, adapted to transmit broadband signals having low cross-correlation between the signals of different transmitters; a plurality of acoustic receivers, mounted inside the streamers, adapted to receive the signals from the transmitters; at least one processor adapted to cross-correlate the signals received at the receivers with copies of transmitter signals to determine identities of the transmitters of the received signals and to determine travel times of the received signals; and a main processor adapted to convert the travel times to distances between the identified transmitters and the receivers and to determine relative positions of the streamers from the distances.