Submarine Landslides and Incised Canyons of the Southeast Queensland Continental Margin
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An investigation conducted aboard the RV Southern Surveyor (SS2013-V01) in January 2013 offshore east Australia collected regional bathymetric data for the continental margin of southern Queensland between Noosa Heads in the south and Indian Head, Fraser Island in the north. This newly mapped area presents a particularly steep portion of continental slope (5–10°) that presents numerous submarine landslides, including two ‘whole-of-slope’ features (the Wide Bay Canyon, and Inskip Slides). The slope is also dissected by three large submarine canyons offshore northern Fraser Island, Wide Bay, and Noosa Heads (i.e. the Fraser Canyons, the Wide Bay Canyon and the Noosa Canyon). Dredge and core samples were collected from slide scars in the northern, central, and southern areas of the bathymetric survey area. The initial examination of the area’s bathymetry, the core and dredge sample sedimentology, and determination of biostratigraphic ages for these sediment samples indicates that the larger submarine slides present in this study area have probably been shed from the slope since the late Pliocene and that canyon incision is currently active on this portion of the slope. In one case, canyon incision is partly responsible for generating slides due to undercutting and removal of the toe of the slope. Slope sediments are dominantly comprised of hemipelagic muds but also include grain-flows and turbidites comprised of shelf-derived sands and upper slope sediment that have abraided the slope muds. The results confirm previous work that indicates that this margin is in an active phase of deconstruction dominated by mass failure.
KeywordsSoutheastern Australian margin Submarine landslides Canyon incision Turbidites Abrasion
We would like to acknowledge the P&O crew and the CSIRO scientific support team who assisted us on the RV Southern Surveyor voyage SS2013-V01 as well as the provision of the CSIRO managed Marine National Facility that is funded by the Australian government. This paper benefitted from thoughtful and constructive reviews by Professor Neville Exon and Dr Asrar Talukdar.
- Boyd R, Keene J, Hubble T, Gardner J, Glenn K, Ruming K, Exon N (2010) Southeast Australia: a cenozoic continental margin dominated by mass transport. In: Mosher DC, Moscardelli L, Baxter CDP et al (eds) Submarine mass movements and their consequences, vol 28, Advances in natural and technological hazards research. Springer, Dordrecht, pp 491–502. doi: 10.1007/978-90-481-3071-9_40 Google Scholar
- Clarke S, Hubble T, Airey D, Yu P, Boyd R, Keene J, Exon N, Gardner J (2012) Submarine landslides on the upper Southeast Australian passive continental margin – preliminary findings. In: Yamada Y, Kawamura K, Ikehara K et al (eds) Submarine mass movements and their consequences, vol 31, Advances in natural and technological hazards research. Springer, Netherlands, pp 55–66. doi: 10.1007/978-94-007-2162-3_5 CrossRefGoogle Scholar
- Clarke S, Hubble T, Airey D, Yu P, Boyd R, Keene J, Exon N, Gardner J, Ward S (2014) Morphology of Australia’s Eastern continental slope and related Tsunami hazard. In: Krastel S, Behrmann J, Volker D, et al. (eds.) Submarine mass movements and their consequences, advances in natural and technological hazards research. Springer International Publishing, Switzerland, 37:529–538Google Scholar
- Dingle R (1983) Slump structures on the outer continental margin of southwestern Africa. Seismic Expression of Structural Styles. Am Assoc Pet Geol Stud Geol 15:1.2Google Scholar
- Fletcher M, Hubble T, Clarke S, Airey D, Yu P (2014) Submarine landslide morphology of Box slides present on the continental slope offshore Fraser Island, Queensland, Australia. Spring Meeting, EGU, ViennaGoogle Scholar
- Hubble TCT (2013) SS 2013-V01 Voyage Summary: Submarine landslides offshore northern New South Wales and southern Queensland; their geomechanical characteristics, timing and triggers. CSIRO Hobart, p 34Google Scholar
- Hubble T, Yu P, Airey D, Clarke S, Boyd R, Keene J, Exon N, Gardner J (2012) Physical properties and age of continental slope sediments dredged from the eastern Australian continental margin – implications for timing of slope failure. In: Yamada Y, Kawamura K, Ikehara K et al (eds) Submarine mass movements and their consequences, vol 31, Advances in natural and technological hazards research. Springer, Dordrecht, pp 43–54CrossRefGoogle Scholar
- Yu P, Hubble T, Airey D, Gallagher S, Clarke S, Keene J, Gardner J (2014) The Wide Bay Canyon system: a case study of canyon morphology on the east Australian continental margin. In: Fall Meeting, AGU, San Francisco, CA, 15–19 Dec. 2014Google Scholar