Nugraha, HD, Jackson, CA-L, Johnson, HD et al. (2 more authors) (2019) Tectonic and oceanographic process interactions archived in Late Cretaceous to Present deep‐marine stratigraphy on the Exmouth Plateau, offshore NW Australia. Basin Research, 31 (3). pp. 405-430. ISSN 0950-091X
Abstract
Deep‐marine deposits provide a valuable archive of process interactions between sediment gravity flows, pelagic sedimentation and thermohaline bottom‐currents. Stratigraphic successions can also record plate‐scale tectonic processes (e.g. continental breakup and shortening) that impact long‐term ocean circulation patterns, including changes in climate and biodiversity. One such setting is the Exmouth Plateau, offshore NW Australia, which has been a relatively stable, fine‐grained carbonate‐dominated continental margin from the Late Cretaceous to Present. We combine extensive 2D (~40,000 km) and 3D (3,627 km2) seismic reflection data with lithologic and biostratigraphic information from wells to reconstruct the tectonic and oceanographic evolution of this margin. We identified three large‐scale seismic units (SUs): (a) SU‐1 (Late Cretaceous)—500 m‐thick, and characterised by NE‐SW‐trending, slope‐normal elongate depocentres (c. 200 km long and 70 km wide), with erosional surfaces at their bases and tops, which are interpreted as the result of contour‐parallel bottom‐currents, coeval with the onset of opening of the Southern Ocean; (b) SU‐2 (Palaeocene—Late Miocene)—800 m‐thick and characterised by: (a) very large (amplitude, c. 40 m and wavelength, c. 3 km), SW‐migrating, NW‐SE‐trending sediment waves, (b) large (4 km‐wide, 100 m‐deep), NE‐trending scours that flank the sediment waves and (c) NW‐trending, 4 km‐wide and 80 m‐deep turbidite channel, infilled by NE‐dipping reflectors, which together may reflect an intensification of NE‐flowing bottom currents during a relative sea‐level fall following the establishment of circumpolar‐ocean current around Antarctica; and (c) SU‐3 (Late Miocene—Present)—1,000 m‐thick and is dominated by large (up to 100 km3) mass‐transport complexes (MTCs) derived from the continental margin (to the east) and the Exmouth Plateau Arch (to the west), and accumulated mainly in the adjacent Kangaroo Syncline. This change in depositional style may be linked to tectonically‐induced seabed tilting and folding caused by collision and subduction along the northern margin of the Australian plate. Hence, the stratigraphic record of the Exmouth Plateau provides a rich archive of plate‐scale regional geological events occurring along the distant southern (2,000 km away) and northern (1,500 km away) margins of the Australian plate.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2018 The Authors. Basin Research © 2018 International Association of Sedimentologists and European Association of Geoscientists and Engineers and John Wiley & Sons Ltd. This is the peer reviewed version of the following article: Nugraha, H. D., Jackson, C. A., Johnson, H. D., Hodgson, D. M. and Reeve, M. T. (2018), Tectonic and oceanographic process interactions archived in the Late Cretaceous to Present deep‐marine stratigraphy on the Exmouth Plateau, offshore NW Australia. Basin Res. Accepted Author Manuscript, which has been published in final form at https://doi.org/10.1111/bre.12328. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. Uploaded in accordance with the publisher's self-archiving policy. |
Keywords: | bottom current; contourites; deep marine; Exmouth Plateau; MTCs; NW Australia; palaeo‐oceanography; seismic reflection; tectonics and sedimentation |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds) > Institute for Applied Geosciences (IAG) (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 15 Nov 2018 09:50 |
Last Modified: | 12 Nov 2019 01:39 |
Status: | Published |
Publisher: | Wiley |
Identification Number: | 10.1111/bre.12328 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:138699 |