Seismic clock timing correction using ocean acoustic waves

摘要

A method for identifying clock timing discrepancies in a plurality of clocks that are each associated with a seismic receiver, comprises the steps of collecting from at least a pair of receivers a data set corresponding to a selected time period, cross-correlating the data sets between at least one pair of receivers so as to produce cross-correlated data for positive, zero, and negative time lags, comparing the cross-correlated data for the positive and negative time lags to measure a timing asymmetry about the zero-lag time, and, for a receiver pair for which there is a non-zero timing asymmetry, using the asymmetry to identify a timing discrepancy between the clocks associated with that receiver pair. The each data set can be filtered so as to obtain data in a selected frequency range, which may avoid an active shot frequency. The data may be collected in the absence of active seismic shots.

主权项

1. A method for identifying clock timing discrepancies in a plurality of clocks that are each associated with a seismic receiver placed on a seafloor in a water column, comprising the steps of:
a) collecting from at least a pair of receivers placed on the seafloor a data set corresponding to a selected time period said data set comprising guided wave arrivals of multi-directional waves propagating through the water column; b) cross-correlating the data sets between at least one pair of receivers so as to produce interferometric data for positive, zero, and negative time lags; c) comparing the interferometric data for the positive and negative time lags to measure a timing asymmetry between causal and acausal events about the zero-lag time; and d) for a receiver pair for which there is a non-zero timing asymmetry between the causal and acausal events, using the asymmetry to identify a timing discrepancy between the clocks associated with that receiver pair.