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Million year old ice found under meter thick debris layer in Antarctica
Author(s) -
Bibby Theodore,
Putkonen Jaakko,
Morgan Daniel,
Balco Greg,
Shuster David L.
Publication year - 2016
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1002/2016gl069889
Subject(s) - geology , debris , glacier , ice core , moraine , cosmogenic nuclide , ice shelf , ice stream , regolith , paleoclimatology , surface exposure dating , physical geography , geomorphology , cryosphere , oceanography , sea ice , climate change , astrobiology , geography , physics , cosmic ray , astrophysics
Cosmogenic nuclide measurements associated with buried glacier ice in Ong Valley, in the Transantarctic Mountains, suggest the preservation of ancient ice. There are three glacial tills on the valley floor which have formed from the concentration of regolith contained within sublimating glacier ice. Two tills are less than 1 m thick and underlain by ice. Measurements of cosmogenic 10 Be, 26 Al, and 21 Ne show that (i) the youngest buried ice unit and corresponding till are at least 11–13 ka, (ii) another ice unit and corresponding intermediate‐age till are at least 1.1 Ma old under any circumstances and most likely older than 1.78 Ma, and (iii) the oldest till is at least 1.57 Ma and most likely greater than 2.63 Ma. These observations highlight the longevity of ice under thin debris layers and the potential to sample ancient ice for paleoclimate/paleoatmosphere information close to the present land surface.