Cooper Basin 2Dcubed seismic reprocessing – polarity-corrected 2D PrSTM lines available for download

Commencing in 2019, TGS has been reprocessing South Australia’s extensive open-file 2D seismic database over the Cooper Basin, using their 2Dcubed technology to generate Pre-Stack Time Migrated and Pre-Stack Depth Migrated 2D and pseudo-3D outputs over the basin. Field data from 3855 lines of 2D seismic data acquired between 1985 and 2012 were used as inputs into the study, which is being undertaken with the support of Chevron Australia Pty Ltd. The area covered by the reprocessing is shown in the map below.

Earlier in 2022, an error in the processing sequence was noticed. The input multi-survey field data was recorded in a mix of SEG-positive and SEG-negative polarities. In order to comply with the standard (SEG-negative) polarity convention used in South Australia whereby an increase in impedance plots as a zero-phase trough, the polarity of any lines which were recorded using SEG-positive polarity (i.e. where an increase in impedance plots as a peak) should have been flipped during the creation of the final SEGY outputs. However, this step was not actually applied where needed and hence the polarity of some of the original published data was wrong.

The Department is pleased to announce that TGS has now delivered the polarity-corrected 2D Pre-Stack Time-Migrated data. Full-offset stacks, velocity data and statics data for all 2D lines are available in one package and angle-stacks are provided separately. All data can be downloaded in ERD’s standardised workstation-ready format using the links below.

The Department is currently QC’ing the full pseudo-3D PrSTM volumes and will publish them as soon as possible. The PrSDM data is expected to be received and published later in 2022.

Downloads

Area in the Cooper Basin covered by the reprocessing