ABSTRACT

Wave-dominated deltas are important hosts for global hydrocarbon reserves, containing significant volumes within good quality, laterally extensive sandstone reservoirs. These deltas often contain an ordered internal architecture with predictable facies distribution patterns identified at a detailed scale in outcrops such as the Cretaceous Blackhawk Formation of the Book Cliffs, Utah, USA. This predictability can be utilised to support reservoir characterisation and modelling in subsurface regions with limited well control and only seismic scale resolution, reducing risk and uncertainty in predicting hydrocarbon volumes. This study illustrates how detailed seismic mapping and attribute extractions were used to refine a sequence stratigraphic framework for a wave-dominated shoreline in the Gippsland Basin. The natural cyclicity of progradational, aggradational and transgressive systems was captured in this assessment, interpreted to have been driven by autocyclic switching, influenced by fluvial input and active extensional tectonism, reworked by waves. Integration of this detailed sequence stratigraphic framework with world class analogues was used to inform facies distributions, supporting predictions for reservoir distribution and quality away from well control.