Early to mid-Pleistocene warm events at the Antarctic margin

Online Access: Get full text
Author(s): McKay, Robert M.; Bendle, James A.; Cook, C.; Dunbar, G.; Dunbar, R. B.; Escutia, C.; González, J. J.; Jiménez, F.; Naish, Tim; Passchier, S.; Riesselman, C. R.; Scherer, R. P.; Tauxe, L.; Toney, Jaime L.; van de Flierdt, Tina; Welsh, K. J.
Integrated Ocean Drilling Program, Expedition 318 Scientists, College Station, TX
Author Affiliation(s): Primary:
Victoria University of Wellington, Wellington, New Zealand
University of Glasgow, United Kingdom
Imperial College London, United Kingdom
Stanford University, United States
University of Granada, Spain
Japan Agency for Marine-Earth Science and Technology, Japan
Montclair State University, United States
U. S. Geological Survey, United States
Northern Illinois University, United States
Scripps Institution of Oceanography, United States
University of Queensand, Australia
Volume Title: AGU 2011 fall meeting
Source: American Geophysical Union Fall Meeting, Vol.2011; American Geophysical Union 2011 fall meeting, San Francisco, CA, Dec. 5-9, 2011. Publisher: American Geophysical Union, Washington, DC, United States
Note: In English
Summary: The response of the Antarctic Ice Sheets and the Southern Ocean to warm events during the Pleistocene is ambiguous. Marine Isotope Stage 31 (MIS; 1.07 Ma) occurred during some of the highest Southern Hemisphere insolation values of the Plio-Pleistocene, and is the last known interval where there is direct evidence that the marine-based Antarctic Ice Sheet was smaller than present in the Ross Embayment, while a carbonate rich interval deposited ∼1 Ma on the continental rise off Prydz Bay has also been documented. We examine a well-dated, new record of Marine Isotope Stage 31 from a continental rise drill core collected during Integrated Ocean Drilling Program Expedition 318 to the Wilkes Land margin of East Antarctica. Marine Isotope Stage 31 is unique in Plio-Pleistocene intervals recovered from Expedition 318 sediment drill cores in that it contains several ∼1m thick intervals of bioturbated carbonate-bearing (i.e. >10% carbonate) mudstones. These are interbedded by massive and finely laminated mudstones indicating a strong cyclicity that is operating at likely Milankovitch-scale frequencies. We present a multi-proxy dataset, including sedimentary, geochemical and microfossil data from planktonic foraminifera, diatoms, bulk sediments, and molecular organic biomarkers, that provides new insight into changing water mass properties and sea-surface temperatures through several Early- to mid-Pleistocene glacial/interglacial cycles, including the peak warmth of MIS 31. Characterizing the sedimentary and geochemical signature of the well-dated MIS 31 interval may also afford an opportunity for identification in Expedition 318 (and other East Antarctic margin) sediments of similar warm periods/glacial cyclicity during Late Pleistocene interglacials. These new records will be examined in the context of records recovered from ANDRILL, Cape Roberts Project and ODP site 1165.
Year of Publication: 2011
Research Program: IODP Integrated Ocean Drilling Program
Key Words: 24 Surficial Geology, Quaternary Geology; Algae; Antarctica; Biomarkers; Cenozoic; Continental margin; Continental rise; Diatoms; East Antarctica; Expedition 318; Foraminifera; Integrated Ocean Drilling Program; Interglacial environment; Lower Pleistocene; MIS 7; Microfossils; Milankovitch theory; Ocean floors; Plankton; Pleistocene; Prydz Bay; Quaternary; Ross Ice Shelf; Southern Ocean; Wilkes Land
Record ID: 2018032740
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data supplied by, and/or abstract, Copyright, American Geophysical Union, Washington, DC, United States

Similar Items