Late Quaternary marginal marine palaeoenvironments of northern Australia as inferred from cluster analysis of coccolith assemblages |
| |
| Institution: | 1. GeoQuest Research Centre, School of Earth and Environmental Sciences, University of Wollongong, NSW 2522, Australia;2. CEREGE, Aix-Marseille Université, CNRS, IRD; Europôle Méditerranéen de l''Arbois, BP 80, 13545 Aix en Provence, France;1. AMB, UiT The Arctic University of Norway, N-9037 Tromsø, Norway;2. NFH, UiT The Arctic University of Norway, N-9037 Tromsø, Norway;3. Marbio, UiT The Arctic University of Norway, N-9037 Tromsø, Norway;1. Science Branch, Department of Fisheries and Oceans Canada, Northwest Atlantic Fisheries Centre, P.O. Box 5667, St. John’s, Newfoundland and Labrador A1C 5X1, Canada;2. Centre for Fisheries Ecosystems Research, Fisheries and Marine Institute of Memorial University of Newfoundland, P.O. Box 4920, St. John’s, Newfoundland and Labrador A1C 5R3, Canada;1. ING PAN – Institute of Geological Sciences, Polish Academy of Sciences, Kraków, Research Centre, BioGeoLab, ul. Senacka 1, 31-002 Kraków, Poland;2. Department of Earth Science, University of Bergen, Postbox 7800, NO-5020 Bergen, Norway;3. Evolution Applied Limited, 59 Higher Lux Street, Liskeard, Cornwall PL14 3JY, UK;1. Shenzhen Key Laboratory of Food Biological Safety Control, The Hong Kong Polytechnic University, Hong Kong Special Administrative Region;2. Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong Special Administrative Region |
| |
| Abstract: | Cluster analyses (R- and Q-mode) were applied to upper Quaternary coccolith assemblages in a sediment core (MD972132) collected in the Gulf of Carpentaria, northern Australia. This shallow gulf is influenced by the Australian monsoon, is tectonally stable and represents an important link between marine and terrestrial palaeoenvironments. The Gulf of Carpentaria is linked to the Pacific Ocean to the east by Torres Strait (12 m water depth) and to the Indian Ocean to the west by the Arafura Sill (53 m water depth), and therefore has been separated from both oceans during sea-level low-stands, resulting in the formation of Lake Carpentaria. Coccolith assemblages in the gulf are similar to modern assemblages in the region, and correspond to typical assemblages in marginal seas. The cluster analysis defines six species assemblages (R-mode), and six groups of samples (i.e., defined by depth in core depth; Q-mode), some with sub-groups, which were deposited under similar environmental conditions. We thus recognised, four major environmental facies over the past 125 ka, corresponding to closed Lake Carpentaria stages, the transitional periods while active channels sporadically connected Lake Carpentaria to the Indian Ocean, and the opening of the Gulf of Carpentaria to the ocean over either one, or both of the sills. Lake Carpentaria was isolated from both oceans through Marine Isotope Stages (MIS) 5d, MIS 4 and MIS 2, and the Gulf of Carpentaria was connected to both oceans during MIS 5c and MIS 1. Torres Strait was emergent during MIS 5b, was flooded again during MIS 5a and persisted as land bridge from MIS 4 to MIS 1. The Arafura Sill was opened from MIS 5c to MIS 5a and episodically connected the Gulf to the Indian Ocean during MIS 3. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
