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Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Oceanography and Atmospheric Sciences and Meteorology

College of Arts and Sciences Faculty Publications

2019

Climate proxies

Articles 1 - 1 of 1

Full-Text Articles in Physical Sciences and Mathematics

The Northwestern Greenland Ice Sheet During The Early Pleistocene Was Similar To Today, Andrew J. Christ, Paul R. Bierman, Paul C. Knutz, Lee B. Corbett, Julie C. Fosdick, Elizabeth K. Thomas, Owen C. Cowling, Alan J. Hidy, Marc W. Caffee Dec 2019

The Northwestern Greenland Ice Sheet During The Early Pleistocene Was Similar To Today, Andrew J. Christ, Paul R. Bierman, Paul C. Knutz, Lee B. Corbett, Julie C. Fosdick, Elizabeth K. Thomas, Owen C. Cowling, Alan J. Hidy, Marc W. Caffee

College of Arts and Sciences Faculty Publications

The multi-million year history of the Greenland Ice Sheet remains poorly known. Ice-proximal glacial marine diamict provides a direct but discontinuous record of ice sheet behavior; it is underutilized as a climate archive. Here, we present a novel multiproxy analysis of an Early Pleistocene marine diamict from northwestern Greenland. Low cosmogenic nuclide concentrations indicate minimal near-surface exposure, similar to modern terrestrial sediment. Detrital apatite (U-Th-Sm)/He (AHe) ages all predate glaciation by >150 million years, suggesting the northwestern Greenland Ice Sheet had, by 1.9 Ma, not yet incised fjords of sufficient depth to excavate grains with young AHe ages. The diamict …