Calcareous nannofossil evidence for marine isotope stage 31 (1 Ma) in core AND-1B, ANDRILL McMurdo Ice Shelf Project (Antarctica)

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doi: 10.1016/j.gloplacha.2009.12.003
Author(s): Villa, Giuliana; Persico, Davide; Wise, Sherwood W.; Gadaleta, Alessia
McMurdo ANDRILL Science Implementation Committee
Author Affiliation(s): Primary:
Universita di Parma, Dipartimento di Scienze della Terra, Parma, Italy
Victoria University of Wellington, New Zealand
Northern Illinois University, United States
GNS Science, New Zealand
Florida State University, United States
Volume Title: Late Neogene chronostratigraphy and depositional environments on the Antarctic margin; new results from the ANDRILL McMurdo Ice Shelf Project
Volume Author(s): Wilson, Gary S., editor; Naish, Timothy R.; Powell, Ross D.; Levy, Richard H.; Crampton, James S.
Source: Late Neogene chronostratigraphy and depositional environments on the Antarctic margin; new results from the ANDRILL McMurdo Ice Shelf Project, edited by Gary S. Wilson, Timothy R. Naish, Ross D. Powell, Richard H. Levy and James S. Crampton; McMurdo ANDRILL Science Implementation Committee. Global and Planetary Change, Vol.96-97, p.75-86. Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0921-8181
Note: In English. 45 refs.; illus., incl. strat. col., sketch map
Summary: ANDRILL Core AND-1B, recovered in the Western Ross Sea of Antarctica, has been examined in search of calcareous nannofossils. Exhaustive and detailed analyses of the interval from 86.61 to 98.99 mbsf revealed for the first time at an extreme southern high latitude (77.88° S) the presence of lower Pleistocene calcareous nannofossils, together with Tertiary and Upper Cretaceous reworked species. Other calcareous microfossils in the assemblage include, spicules of calciosponges and small foraminifers. The short normal magnetozone between 84.97 and 91.13 mbsf is correlated with the Jaramillo Subchron (C1r.1n) (Wilson et al., 2007). The presence of nannofossils in the biogenic interglacial sediments is consistent with an episode of warm surface waters and open-marine conditions during the Jaramillo subchron, at ∼1 Ma, which corresponds with Marine Isotope Stage (MIS)-31 (Scherer et al., 2007; Naish et al., 2007). Climate proxies such as oxygen isotope stratigraphy and calcareous nannofossils at ODP Site 1165 (Pospichal, 2003; Villa et al., 2008) and the diatom assemblage in a shelly carbonate sequence at Cape Roberts 1 (Bohaty et al., 1998) also support a warming event during this time and suggest it extended around the Antarctic Continent. This in turn implies a total or partial collapse of the McMurdo Ice Shelf and a concurrent shift or temporary dissipation of the Polar Front (Antarctic Convergence) and Antarctic Divergence that currently serve as barriers to the influx of calcareous nannofossils to the margins of Antarctica. Abstract Copyright (2012) Elsevier, B.V.
Year of Publication: 2012
Research Program: ODP Ocean Drilling Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; ANDRILL; Algae; Antarctica; Biostratigraphy; Calcareous composition; Cenozoic; Leg 188; MIS 31; Marine environment; McMurdo Ice Shelf; McMurdo Sound; Microfossils; Nannofossils; Neogene; ODP Site 1165; Ocean Drilling Program; Paleoclimatology; Paleoenvironment; Plantae; Pleistocene; Pliocene; Programs; Quaternary; Ross Ice Shelf; Ross Sea; Southern Ocean; Tertiary
Coordinates: S642300 S642200 E0671400 E0671300
S780000 S750000 E1670000 E1623000
Record ID: 2013002370
Copyright Information: GeoRef, Copyright 2018 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands