Neogene siliciclastic deposition and climate variability on a carbonate margin; Australian Northwest Shelf

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doi: 10.1016/j.margeo.2018.06.007
Author(s): Tagliaro, Gabriel; Fulthorpe, Craig S.; Gallagher, Stephen John; McHugh, Cecilia M.; Kominz, Michelle; Lavier, Luc L.
Author Affiliation(s): Primary:
University of Texas-Austin, John A. and Katherine G. Jackson School of Geosciences, Institute for Geophysics, Austin, TX, United States
University of Melbourne, Australia
CUNY Queens College, United States
Western Michigan University, United States
Volume Title: Marine Geology
Source: Marine Geology, Vol.403, p.285-300. Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0025-3227 CODEN: MAGEA6
Note: In English. 90 refs.; illus., incl. sects., 1 table, sketch map
Summary: The Bare Formation represents a unique episode of Neogene siliciclastic deposition on the carbonate-dominated Australian Northwest Shelf (NWS). Seismic interpretation coupled with age control from International Ocean Discovery Program (IODP) Expedition 356 Sites U1462, U1463 and U1464 allow us to constrain the timing of siliciclastic deposition and the associated sedimentary processes. The Bare Formation is preceded by middle to late Miocene shelf exposure and karstification (∼12 Ma). Elongate sandbars deposits with small lobate deltas developed during the late Miocene. Fluvial deposition increased markedly in the Zanclean (5.3-3.6 Ma), resulting in development of a large wave dominated delta, with evidence of channels, comprising the thickest component of the Bare Formation. Siliciclastic input decreased in the Piacenzian (3.6-2.58 Ma), leading to margin retreat and final termination in the early Pleistocene (∼2.39 Ma). The results correlate with regional climate and sedimentary records from Sites U1463 and U1464, which indicate an arid middle to late Miocene on the NWS, followed by a humid interval in the Zanclean and a return to arid conditions during the Piacenzian. We suggest that fluctuation of surface runoff patterns in the continental hinterland was the primary control on Bare Formation evolution. Sedimentary and climate transitions are linked to reorganization of Indian Ocean paleoceanography, accompanying northward migration of the Australian continent and progressive restriction of the Indonesian Throughflow.
Year of Publication: 2018
Research Program: IODP Integrated Ocean Drilling Program
IODP2 International Ocean Discovery Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; 20 Geophysics, Applied; Australasia; Australia; Bare Formation; Biostratigraphy; Carnarvon Basin; Cenozoic; Chemostratigraphy; Core; Depositional environment; Expedition 356; Geophysical methods; Geophysical profiles; Geophysical surveys; IODP Site U1462; IODP Site U1463; IODP Site U1464; Indian Ocean; International Ocean Discovery Program; Lithostratigraphy; Marine sediments; Neogene; North West Shelf; Paleoclimatology; Sediments; Seismic methods; Seismic profiles; Seismic stratigraphy; Siliciclastics; Surveys; Tertiary; Western Australia
Coordinates: S194917 S194917 E1154237 E1154237
S185755 S185755 E1173726 E1173726
S180355 S180355 E1183753 E1183753
Record ID: 2019017012
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands