The Otway Basin Regional Study integrated the new OB2020 seismic survey and reprocessed legacy 2D data to provide regional interpretation and petroleum system modelling for the Deep-water Offshore Otway Basin. This work has resulted in an improved understanding of the hydrocarbon prospectivity of the deep-water areas of the Otway Basin.
Figure 1: Otway Basin Regional Petroleum System Study 2D and 3D PSM model locations
Utilising the new depth imaged OB2020 seismic data with depth imaged legacy seismic to tie to inboard wells, six 2D composite dip lines were modelled, each tying at least one key well to constrain; the interpretation, litho and organo-facies assignment and distribution, erosion reconstruction, and thermal calibration.
Unlike the inboard Otway Basin where Austral 1 and 2 are the active petroleum systems, the Austral 3 is the postulated petroleum system, due to burial by a thick late Cretaceous succession. Although no Austral 3 source rock has been penetrated by wells to date, modelling shows potential for plays in the deep-water Otway Basin; depending on timing of hydrocarbon generation and trap formation.
Figure 2 Interpretation of major sequence boundaries along 2D PSM line 2 in the northwest Offshore Otway Basin
Figure 3: Thermal calibration results for Breaksea Reef 1
Figure 4: Hydrocarbon migration results for 2D PSM line 2 northwest Offshore Otway Basin.
The seismic products this study used are already available via NOPIMS. The full report is now available under the Otway Basin MC 2D MSS 2020 survey.
The interpretation used in model generation will be available for download in the near future.