The long-term evolution of continental and other deep sea margin systems (e.g. oceanic islands) holds clues to the origins of modern coastal environments, the occurrence and distribution of marine resources, and the potential for future coastal hazards. In the case of Australia, the evolution of the continent through geological time has direct implications for the nation’s marine sovereignty and access rights to natural resources.
Deep marine sedimentary systems (DMSS) are a current focal point of the Geocoastal Research Group, with members of the group currently investigating the evolution of Australia’s continental margin, with a diverse range projects looking at the causes and consequences of submarine landslides – including their tsunamigenic potential, the role of submarine canyons in delivering sediments from the shelf to the basin and issues around marine sovereignty.

Tsunamogenic Submarine Landslides

Members of the Geocoastal Research Group are leading a long-term study looking at submarine erosion and landsliding on the Australian eastern seaboard. Newly acquired high-resolution multibeam, seismic, and sedimentological data are used to test geological and geotechnical models explaining the causes, consequences and frequency of submarine landslide events. We aim to understand the geological development of the margin, the potential for tsunamis induced by submarine landslides in this region and ultimately enable an evaluation of the risks this natural hazard presents to Australia’s coastal towns and cities.

Core on deck! Cores collected from the seafloor onboard the RV Southern Surveyor

Coring on deck! Waiting for the core to arrive…

• A/Prof Tom Hubble
  
• A/Prof Jock Keene
• Dr Samantha Clarke – Lecturer
• Phyllis Yu – PhD candidate Current
• Melissa Fletcher – Masters candidate Current

For collaboration or Honours, Masters, or PhD research projects please contact:

Tom Hubble – tom.hubble@sydney.edu.au

Samantha Clarke – samantha.clarke@sydney.edu.au

Controls on Deepwater, Gravity Driven Sedimentation on the Northeast Australian Margin

The NE Australian margin represents the largest, extant mixed siliciclastic-carbonate continental margin. Despite the scale of the system, the Great Barrier Reef submarine canyons and landslides, and the processes that control the transport and fate of sediments from the shelf to the basin via these mechanisms, are very poorly understood. The GRG and collaborators have recently discovered that margin is heavily incised by submarine canyons and scarred by large undersea landslides that carry huge volumes of sediment gravity deposits into basin.

Undersea landslide discovered edge off Townsville (After Webster et al. 2016)

Our work provides new insights in to how these processes operate on mixed siliciclastic-carbonate margins. Recent work by the GRG and other groups confirms that the classical models of margin sedimentation – both fine and coarse grained – do not work on this type of mixed siliciclastic-carbonate margin. Further, new work integrating field observations with sophisticated numerical modelling suggests that some of the submarine landslides discovered along the NE Australian had the potential to produce significant tsunamis.

In April-May 2017 the GRG, in collaboration with German scientists from the MARUM (Bremen,

TACTEAC 2017 Sonne cruise

Germany), participated in a research cruise aboard the RV Sonne along the entire length of the GBR

margin. This cruise was focused on reconstructing the past activity of the East Australian Current (EAC) (TACTEAC, Temperature And Circulation History of The East Australian Current, Auckland (New Zealand)–Darwin (Australia), 17 April–09 May 2017 ) but we also collected a wealth of new data (multibeam, seismics, sediment cores, bottom video) that will enable us to better understand the source to sink system.

New data collected on the Sonne in 2017.

If you are interested in more information on this research, please contact our researchers below. For future student projects in this field see Student Opportunities.

Research team

A/Prof Jody Webster
Dr Robin Beaman (JCU)
Dr Angel Puga-Bernabeu (USYD/Uni. Granada)
Professor Mary Elliot (Uni. Nantes)
Dr Raphael Wust (JCU/TRICAN Canada

For collaboration or Honours, Masters, or PhD research projects please contact:

Jody Webster – jody.webster@sydney.edu.au

Australia’s Continental Margin Evolution

Coming soon!

Marine Sovereignty

Coming soon!