Preservation of a preglacial landscape under the center of the Greenland Ice Sheet.
Continental ice sheets typically sculpt landscapes via erosion; under certain conditions, ancient landscapes can be preserved beneath ice and can survive extensive and repeated glaciation. We used concentrations of atmospherically produced cosmogenic beryllium-10, carbon, and nitrogen to show that ancient soil has been preserved in basal ice for millions of years at the center of the ice sheet at Summit, Greenland. This finding suggests ice sheet stability through the Pleistocene (i.e., the past 2.7 million years). The preservation of this soil implies that the ice has been nonerosive and frozen to the bed for much of that time, that there was no substantial exposure of central Greenland once the ice sheet became fully established, and that preglacial landscapes can remain preserved for long periods under continental ice sheets.
Department of Geology and Rubenstein School of the Environment and Natural Resources, University of Vermont, Burlington, VT 05405, USA.
Paul R
PR
Bierman
Lee B
LB
Corbett
Joseph A
JA
Graly
Thomas A
TA
Neumann
Andrea
A
Lini
Benjamin T
BT
Crosby
Dylan H
DH
Rood