Mid-late Pleistocene glacial evolution in the Grove Mountains, East Antarctica, constraints from cosmogenic Be-10 surface exposure dating of glacial erratic cobbles

• Published in: Quaternary Science Reviews
• Main Authors: Dong, Guocheng, Huang, Feixin, Yi, Chaolu, Liu, Xiaohan, Zhou, Weijian, Caffee, Marc W.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2016
• Subjects: Mount Harding; Grove Mountains; East Antarctic Ice Sheet; Cosmogenic Be-10 Exposure Dating; Blue-ice Moraine; Science & Technology; Physical Sciences; BLUE-ICE AREAS; DRONNING MAUD LAND; PRODUCTION-RATES; VICTORIA LAND; SHEET; AGES; NUCLIDES; HISTORY; DEGLACIATION; THICKNESS; Physical Geography; Geology; Geography; Physical; Geosciences; Multidisciplinary; Antarctic; East Antarctica; Dronning Maud Land; Victoria Land; Harding; Antarc*; Antarctica; Ice Sheet
• Online Access: http://ir.ieecas.cn/handle/361006/5705; https://doi.org/10.1016/j.quascirev.2016.05.030

Glacial histories from the East Antarctic Ice Sheet (EAIS) provide keys to understanding correlations between the EATS and global climate. They are especially helpful in the assessment of global sea level change, and as a means of quantifying the magnitude of past glacial activity and the rate at which ice responded to climate change. Given the significance of EAIS glacial histories, it is imperative that more glacial chronologic data for this region be obtained, especially for the mid-to-late Pleistocene. We report cosmogenic Be-10 surface exposure dating results from glacially transported cobbles embedded in blue-ice moraine material at Mount Harding, the Grove Mountains, EAIS. Forty exotic cobbles sampled along two profiles (A and B) on this blue-ice moraine present apparent exposure-ages ranging from 7.2 to 542.2 ka. We explore this scattered dataset by using Principal Component Analysis (PCA) to identify statistically significant trends in the data. We identify a correlation between exposure-age and distance of the cobbles from Mount Harding. In profile A, cobbles further from Mount Harding yield older exposure-ages than those that are relatively close. In profile B, cobbles closer to Mount Harding are found to have relatively older exposure-ages. In term of glacial history we suggest that the direction of ice flow changed during the period from similar to 60 to 200 ka, and that multiple glacial fluctuations occurred in the mid-late Pleistocene. (C) 2016 Elsevier Ltd. All rights reserved.