Towards updated stratigraphic frameworks for Australia

Abstract

A standardised and precise timescale is invaluable to geological research and crucial to meaningful correlation at local, regional and global scales for both researchers and industry. Modern techniques and instruments are delivering increasingly accurate ages, and biozonation schemes are continually refined and standardised on a global basis. Updates to the international geologic time scale occur regularly, and constant updates to stratigraphic schemes are required to ensure that major regional geological events can be correlated across the Australian margin. Several different sequence stratigraphic schemes have been developed for the basins of the North West Shelf. These range from basin-specific to margin-wide schemes. While these schemes have much in common, there are some significant differences. Understanding the nature and reasons for both the differences and commonalities is an essential step for improving understanding of the region’s evolution. The continuing improvements being made to biostratigraphic zonation schemes for the Triassic to Cenozoic will assist in better defining sequences and correlations, and allow geologists to better understand whether apparent differences in sequence definition across the margin are real, and therefore if they reflect different basin histories or are simply an artefact of biostratigraphic imprecision. Geoscience Australia endeavours to—in collaboration with industry—produce unified stratigraphic schemes for the various hydrocarbon provinces. This work will fundamentally support present and future acreage releases.