Abstract: A method is disclosed for determining the separation between a seismic energy source and a seismic sensor, the location of which is known imperfectly. After the source emits a wavefield, the first-arriving impulse at the sensor is statistically processed to form a range statistic that is related to the true travel time between the source and the sensor. A set of range statistics from a plurality of source positions are filtered and converted to range loci, the intersection of which marks the location of the sensor.

Abstract: In a marine seismic survey, a method for measuring the acoustic properties of the water mass at each seismic station along a line of survey by recovering acoustic reflections from discrete discontinuities within the water above the water-bottom reflection. A profile of the velocity distribution within the water column is calculated from a conventional velocity analysis.

Abstract: A method for properly migrating seismic data which has been elevation-static corrected. The method is comprised of assigning a zero (or very small) migration velocity for data located below a datum, yet above the original recording surface elevation. A best estimated earth velocity is input into the migration algorithm to represent the earth below the original recording surface. For seismic data collected in water-covered environments where the water bottom is irregular, the method contemplates that the data lying above the water bottom are migrated using the migration velocity of water. The data lying at or below the water bottom are migrated with a migration velocity of zero. In a second step, are elevation-static corrected and migration is performed where the velocity is zero between the datum and the original surface. Data below the surface is migrated using the estimated earth velocity.

Abstract: A method for removing boundary-generated artifacts in synthetic and actual seismic data. After seismic data processing, undesirable boundary-generated artifacts appear in the final seismic section. To remove this unwanted noise from the section, zeros are added to the lower boundary of the seismic section. This essentially pushes the sources of the noise downward in time in the section. After padding with zeros, the seismic data is collapsed to their point sources of origin using the Stolt migration/diffraction algorithm. Once the data are collapsed, the size of the seismic section is reduced to its original size. Following the resizing of the section, the inverse of the earlier applied Stolt algorithm is applied to return the seismic data to its original form, minus the boundary-generated artifacts.

Abstract: A method for identifying anomalous noise amplitudes in seismic records by deriving a measured amplitude factor over predetermined periods of time or time windows for a predetermined number of traces comprising the records is disclosed. A noise-free amplitude factor for the same periods of time and number of traces is also computed using a Gauss-Siedel method of matrix inversion. A ratio of the measured and noise-free amplitude factors is made to determine a correction factor which is compared to a user defined threshold value for determining a presence of anomalous noise amplitudes in the seismic records. Based on the comparison of the correction factor to the threshold value, the user determines whether to suppress or correct traces experiencing the anomalous noise amplitudes.