Abstract: A method is provided for accurately determining the physical location of a deployed seismic geophone used in seismic investigations by using a portable navigational satellite receiver to obtain a set of navigational satellite measurements providing the position of the deployed geophone at the time of deployment of the geophone into the earth. A method is provided for automatically and accurately identifying and determining the physical location of a deployed geophone used in seismic investigations by using one or more portable navigational satellite receivers and an automatic geophone identification and tracking system at the time of geophone deployment.

Abstract: A method of controlling a streamer positioning device (18) configured to be attached to a marine seismic streamer (12) and towed by seismic survey vessel (10) and having a wing and a wing motor for changing the orientation of the wing. The method includes the steps of: obtaining an estimated velocity of the streamer positioning device, calculating a desired change in the orientation of the wing using the estimated velocity of the streamer positioning device, and actuating the wing motor to produce the desired change in the orientation of the wing. The invention also involves an apparatus for controlling a streamer positioning device including means for obtaining an estimated velocity of the streamer positioning device, means for calculating a desired change in the orientation of the wing using the estimated velocity of the streamer positioning device, and means for actuating the wing motor to produce the desired change in the orientation of the wing.

Abstract: A method and apparatus for utilizing seismic data contemporaneously across multiple seismic domains is disclosed. The method comprises kinematically linking a first point in a set of seismic data having at least three-dimensions in a first seismic domain with a second point in the set of seismic data in a second seismic domain related to the first seismic domain by a velocity model in time or in depth. The apparatus includes, in various aspects, a program storage medium encoded with instructions that, when executed by a computer, perform such a method and a computer programmed to perform the method.

Abstract: A method of processing seismic data, for example surface seismic data such as multi-component OBC (Ocean Bottom Cable) seismic data, comprises using vertical seismic profile (VSP) seismic data to determine a model of the relationship between depth within the earth and the velocity of seismic energy. In one embodiment, an model of the relationship between depth and velocity of seismic energy for P-waves is calibrated using VSP seismic data. Then, a model of the relationship between depth and velocity of seismic energy for S-waves is calibrated using VSP seismic data. Initially the models are calibrated for the vertical velocity of P-waves and S-waves, using zero-offset or low-offset VSP data. The models may then undergo further calibration steps, such as calibration for VTI anisotropy and anelastic attenuation. Once calibration is complete, the models are used to process surface seismic data.

Abstract: A method for contemporaneously utilizing seismic data in the pre-stack seismic domain and the post-stack seismic domain is disclosed. The method includes initiating a higher order probe at a three-dimensional coordinate in a post-stack seismic volume; and instantiating a pre-stack seismic data content for the higher order probe. In alternative aspects, the invention includes a program storage medium encoded with instructions that, when executed by a computer, perform the method and a computer programmed to perform the method.

Abstract: The present invention provides methods to be used in seismic data processing to address problems encountered during data acquisition. The present invention provides a multi-step process to reduce aliasing of seismic data along time slices.

Abstract: A deflector device for use with a tow line between a seismic survey vessel and a tow, in particular a streamer or streamer array, in the water behind the vessel comprises a vertically oriented wing-shaped body for producing a sideways force as it is towed through the water, and a towing bridle adapted to connect the wing-shaped body to the tow line. The bridle comprises first and second connecting elements connected between the tow line and respective longitudinally-spaced points along the high pressure side of the wing-shaped body. The wing-shaped body includes one or more buoyancy elements to render it slightly positively buoyant, and the length of at least one of the connecting elements is adjustable by remote contol in order to tilt the wing-shaped body. This gives the sideways force a vertical component, and so allows remote control of the depth of the deflector device, as well as its lateral offset from the vessel.

Abstract: A method of acquiring and processing seismic data including: acquiring digitized seismic data associated with a plurality of moving receiver points using a plurality of seismic sensors; attenuating noise in the moving receiver point based digitized seismic data using digitized seismic data associated with a plurality of nearby receiver points; transforming noise attenuated moving receiver point based digitized seismic data into stationary receiver point based digitized seismic data; and recording noise attenuated and transformed digitized seismic data associated with stationary receiver points having an average spatial separation interval at least twice the average moving receiver point spatial separation interval. This method is particularly effective at attenuating coherent low frequency noise and correcting for the receiver motion effect in marine seismic data.

Abstract: A valve has an input (3,13) and first and second outputs (4, 5; 14, 15). The valve also has a closure member (2, 12) that is operable to isolate the first output from the input, to isolate the second output from the input, to isolate both outputs from the input, or to connect both outputs to the input. In one embodiment, the input (13) and the first and second outputs (14, 15) are disposed in a flat valve face (16) in a valve body. The closure member (12) has a sealing face (17?) that is biased against the valve face (16). A recess (18) is provided in the sealing end face (17?) of the closure member (12). The recess is so shaped, and the input (13) and outputs (14, 15) are so positioned that rotation of the closure member (12) by successive angles of 90° puts the valve in the following states: both outputs connected to the input, one of the outputs connected to the input, the other of the outputs connected to the input, and both outputs isolated from the input.

Abstract: A method of seismic surveying using one or more vibrational seismic energy sources activated by sweep signals. The highest order harmonic that has sufficient strength to cause significant harmonic distortion of a sweep segment is determined. A number of sweep segments in excess of the number of sources is selected. Initial phase angles are selected for each sweep segment of each seismic energy source so that substantially all harmonics up to and including the highest order harmonic are suppressed. Using cascaded sweeps, seismic data are acquired and processed to substantially attenuate harmonics upto the selected order.

Abstract: The present invention provides a method for reducing water bottom reflection time differences. The method includes selecting a plurality of trace groups, each trace having an offset from a midpoint and a water bottom reflection time. The method also includes determining a rate of change of the water bottom reflection time of each trace and generating a model water velocity and a model water bottom reflection time for each trace midpoint using a preselected function of the water bottom reflection times and the rates of change. Furthermore, the method includes generating a plurality of water bottom reflection time corrections for the traces in each trace group using a pre-selected function of the water bottom reflection times, the model water bottom reflection times, the model water velocities, and the trace offsets.