An example of seismic time picking by third‐order bicoherence

Abstract

Conventional seismic time‐delay estimation relies on the crosscorrelation that quantifies the similarities between two measurements in the second‐order time domain. When the noise correlation in the measurements is considerable, the correlation peak can be substantially distorted, resulting in imprecise and even biased estimation of the time delay. The synthetic data computed by Ikelle et al. (1993) and Ikelle and Yung (1994) in their studies of wave propagation through random media provide a good example of data with considerable noise correlation. In picking the arrival times in this data set, we found that the crosscorrelation technique suffers both from the severely restricted signal bandwidth and from the presence of coda. Here we present an alternative approach involving high‐resolution nonparametric time‐delay estimation in the third‐order domain.