Late Pliocene age of glacial deposits at Heidemann Valley, East Antarctica: evidence for the last major glaciation in the Vestfold Hills

• Main Authors: Colhoun, Eric A., Kiernan, Kevin W., McConnell, Anne, Quilty, Patrick G., Fink, David, Murray-Wallace, Colin V., Whitehead, Jason
• Other Authors: The University of Newcastle. Faculty of Science & Information Technology, School of Environmental and Life Sciences
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Cambridge University Press 2009
• Subjects: amino acid racemization dating; diatoms; foraminifera; magnetic polarity; origin; Sørsdal Glacier; trench excavation; Antarctic; Bardin Bluffs; East Antarctic Ice Sheet; East Antarctica; Heidemann Valley; Prince Charles Mountains; Prydz Bay; Ross Sea; Vestfold; Vestfold Hills; Antarc*; Antarctic Science; Antarctica; Ice Sheet
• Online Access: http://hdl.handle.net/1959.13/925155

A Pliocene (2.6–3.5 Ma) age is determined from glacial sediments studied in a 20m long, 4m deep trench excavated in Heidemann Valley, Vestfold Hills, East Antarctica. The age determination is based on a combined study of amino acid racemization, diatoms, foraminifera, and magnetic polarity, and supports earlier estimates of the age of the sedimentary section; all are beyond ¹⁴C range. Four till units are recognized and documented, and 16 subunits are identified. All are ascribed to deposition during a Late Pliocene glaciation that was probably the last time the entire Vestfold Hills was covered by an enlarged East Antarctic Ice Sheet (EAIS). Evidence for other more recent glacial events of the ‘Vestfold Glaciation’ may have been due to lateral expansion of the Sørsdal Glacier and limited expansion of the icesheet margin during the Last Glacial Maximum rather than a major expansion of the EAIS. The deposit appears to correlate with a marine deposition event recorded in Ocean Drilling Program Site 1166 in Prydz Bay, possibly with the Bardin Bluffs Formation of the Prince Charles Mountains and with part of the time represented in the ANDRILL AND-1B core in the Ross Sea.