EGU22-3848
https://doi.org/10.5194/egusphere-egu22-3848
EGU General Assembly 2022
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Sedimentary evidence for a Quaternary mega-tsunami in NW Australia

Piers Larcombe1, Moyra Wilson2, Thomas Whitley3, Ingrid Ward4, Duncan Pirrie5, Tanghua Li6, Jon Hill7, Veronique Florec8, and Mark Bateman9
Piers Larcombe et al.
  • 1Archaeology, University of Western Australia, Perth, Australia (piers.larcombe@uwa.edu.au)
  • 2Earth Sciences, University of Western Australia, Perth, Australia (moyra.wilson@uwa.edu.au)
  • 3Anthropology, Sonoma State University, Rohnert Park, USA (thomas.whitley@sonoma.edu)
  • 4Archaeology, University of Western Australia, Perth, Australia (ingrid.ward@uwa.edu.au)
  • 5Applied Science, University of South Wales, UK (duncan.pirrie@southwales.ac.uk)
  • 6Earth Observatory of Singapore, Nanyang Technological University, Singapore (li.tanghua@ntu.edu.sg)
  • 7Environment and Geography, University of York, York, UK (jon.hill@york.ac.uk)
  • 8Centre for Environmental Economics and Policy, University of Western Australia, Perth, Australia (veronique.florec@uwa.edu.au)
  • 9Geography, University of Sheffield, Sheffield, UK (m.d.bateman@sheffield.ac.uk)

Tsunamis can cause catastrophic impacts at the coastline. Australia’s NW continental margin displays abundant massive slope-failure deposits, but there is little evidence of associated coastal tsunami deposits. Here we report on investigations of an exposed field of cemented dunes and associated conglomero-breccias, located on Barrow Island. Preliminary OSL dating indicates that these deposits formed when relative sea level was around 30 to 50 m below present. If the deposits can be interpreted as having been formed by a mega-tsunami, then it was a very significant event that ran inland several km and achieved a maximum run-up of several tens of metres. A similar event today would directly impact thousands of people, multiple ports, and industrial facilities worth many billions of dollars, as well as impacting many unique ecological and cultural resources.

How to cite: Larcombe, P., Wilson, M., Whitley, T., Ward, I., Pirrie, D., Li, T., Hill, J., Florec, V., and Bateman, M.: Sedimentary evidence for a Quaternary mega-tsunami in NW Australia, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-3848, https://doi.org/10.5194/egusphere-egu22-3848, 2022.