Benthic foraminiferal abundances from eight sites of the Northwest Australian shelf
Citation
Gallagher S J, Wallace M W, Li C L, Kinna B, Bye J A T, Akimoto K, Torii M (2009). Benthic foraminiferal abundances from eight sites of the Northwest Australian shelf. PANGAEA - Publishing Network for Geoscientific and Environmental Data. Occurrence dataset https://doi.org/10.1594/pangaea.758377 accessed via GBIF.org on 2023-02-09.Description
Foraminiferal analysis of Miocene to recent strata of the Northwest Shelf of Australia is used to chart West Pacific Warm Pool (WPWP) influence. The assemblage is typified by "larger" foraminifera with ingressions of the Indo-Pacific "smaller" taxa Asterorotalia and Pseudorotalia at around 4 Ma and from 1.6 to 0.8 Ma. A review of recent and fossil biogeography of these taxa suggests their stratigraphic distribution can be used to document WPWP evolution. From 10 to 4.4 Ma a lack of biogeographic connectivity between the Pacific and Indian Ocean suggests Indonesian Throughflow (ITF) restriction. During this period, the collision of Australia and Asia trapped warmer waters in the Pacific, creating a central WPWP biogeographic province from the equator to 26°N. By 3 Ma Indo-Pacific species migrated to Japan with the initiation of the "modern" Kuroshio Current coinciding with the intensification of the North Pacific Gyre and Northern Hemisphere ice sheet expansion. Indo-Pacific taxa migrated to the northwest Australia from 4.4 to 4 Ma possibly because of limited ITF. The absence of Indo-Pacific taxa in northwest Australia indicates possible ITF restriction from 4 to 1.6 Ma. Full northwest Australian biogeographic connectivity with the WPWP from 1.6 to 0.8 Ma suggests an unrestricted stronger ITF (compared to today) and the initiation of the modern Leeuwin Current. The extinction of some Indo-Pacific species in northwest Australia after 0.8 Ma may be related to the effects of large glacial/interglacial oscillations and uplift of the Indonesian Archipelago causing Indonesian seaway restriction.Taxonomic Coverages
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Chromistarank: kingdom
Geographic Coverages
Event: Austin-1,
North west Australian continental margin
; Event: Bounty-1,
North west Australian continental margin
; Event: Goodwyn-6,
North west Australian continental margin
; Event: Goodwyn-7,
North west Australian continental margin
; Event: Maitland-1,
North west Australian continental margin
; Event: Matiland_North-1,
North west Australian continental margin
; Event: Tryal_Rocks-1,
North west Australian continental margin
; Event: West_Tryal_Rocks-1,
North west Australian continental margin
;
Bibliographic Citations
Contacts
Stephen John Gallagheroriginator
Malcolm W Wallace
originator
Chung Leong Li
originator
Belinda Kinna
originator
John A T Bye
originator
Kazumi Akimoto
originator
Masayuki Torii
originator
metadata author
PANGAEA - Data Publisher for Earth & Environmental Science
email: info@pangaea.de
homepage: https://www.pangaea.de
administrative point of contact
PANGAEA - Data Publisher for Earth & Environmental Science
email: info@pangaea.de
homepage: http://www.pangaea.de