The ‘Ocean’s Overture’ on the North West Shelf of Australia

Abstract

The North West Shelf of Australia presents problems in data acquisition and processing. In particular the hard water bottom and near surface prograding carbonate wedge set up a standing wave multiple train analogous to that of a closed organ pipe. This strong multiple energy and the observed rapid attenuation of the high frequencies in the source spectrum degrade the quality of the recorded data. The data quality can be improved by careful selection of the acquisition parameters. The multiple energy appears to be reduced by reducing the output power of the source and restricting the high frequency end of the source spectrum to useable frequencies. The frequencies in the low range of the seismic spectrum can be used to improve the seismic data through broadening of the bandwidth and improved penetration.