Automatic traveltime picking using the instantaneous traveltime

Conclusions

We have presented a novel approach to automatic event picking in seismic data. This method does not require a specification of optimal empirical parameters, such as window lengths or reference waveforms. It is based on the instantaneous traveltime, a new attribute. The instantaneous traveltime is computed from the seismic data by first transforming the data into a time-frequency domain to capture the nonstationary behavior of the data. Then, the time-frequency representation of the data is mapped back onto the time domain. The time-frequency transform as well as the mapping operation may be chosen depending on the data at hand. Furthermore, the time-frequency transform need not have an exact inverse transform, a fact which allows for a wider range of choices on such transforms.

We have applied this approach to synthetic and field data (dynamite and Vibroseis) to investigate the behavior of the algorithm. We find that its performance is promising. Although the presented method cannot be used for first-break picking per se, the instantaneous traveltime attribute can be used for such a task. To improve the accuracy of the proposed method, information on adjacent traces may be used to further constrain the event-picking and/or edge-linking algorithms.

Automatic traveltime picking using the instantaneous traveltime