The last deglacial retreat history of the East Antarctic Ice Sheet recorded in sediments from off the Wilkes Land coast

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Author(s): Yamane, Masako; Yokoyama, Yusuke; Miyairi, Yosuke; Suga, Hisami; Dunbar, Robert B.; Ohkouchi, Naohiko
Author Affiliation(s): Primary:
University of Tokyo, Chiba, Japan
Japan Agency for Marine-Earth Science and Technology, Japan
Stanford University, School of Earth Sciences, United States
Volume Title: AGU 2017 fall meeting
Source: American Geophysical Union Fall Meeting, Vol.2017; American Geophysical Union 2017 fall meeting, New Orleans, LA, Dec. 11-15, 2017. Publisher: American Geophysical Union, Washington, DC, United States
Note: In English
Summary: Timing of past ice sheet retreat of Antarctic continent has been debated with regards to the global sea level changes since the Last Glacial Maximum (LGM) centered at around 20 ka. Exposure dating using cosmogenic radio nuclide (CRN) for glacial deposits have been widely used to reconstruct the last deglacial history though this cannot apply where no-ice free coasts are existed. One such location is the Wilkes Land where the East Antarctic Ice Sheet (EAIS) is situated directory on seafloor. Sediment cores obtained off the Wilkes Land coast successfully retrieved cores during the Integrated Ocean Drilling Program (IODP) Expedition 318 (Escuita et al., 2011). Major obstacle to obtain reliable chronology for marine cores around Antarctica is sparsity of carbonate materials such as foraminifera. Thus compound-specific radiocarbon analysis (CSRA) has been used, and we applied CSRA to the sediments obtained off the Wilkes Land coast. The CSRA targeted C16 and C16:1 fatty acid due to their high degradation rate. Hence low concentrations of these compounds are expected. We found major sedimentation occurred since the beginning of Holocene. The result is then compared to the previously reported dates from the land based CRN dates (eg., Mckintosh et al., 2013; Yamane et al., 2011) to discuss the timing of retreat of EAIS.
Year of Publication: 2017
Research Program: IODP Integrated Ocean Drilling Program
Key Words: 24 Surficial Geology, Quaternary Geology; Antarctic ice sheet; Antarctica; Cenozoic; Climate change; Deglaciation; East Antarctic ice sheet; Expedition 318; Glacial geology; Glaciation; Integrated Ocean Drilling Program; Quaternary; Southern Ocean; Wilkes Land
Coordinates: S663000 S631500 E1440000 E1354500
Record ID: 2019025672
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