Directly dating postglacial Greenlandic land-surface emergence at high resolution using in situ 10Be
File(s)YQRES-D-16-00171_R2 copy.pdf (4.21 MB)
Accepted version
Author(s)
Bierman, Paul R
Rood, Dylan H
Shakun, Jeremy D
Portenga, Eric W
Corbett, Lee B
Type
Journal Article
Abstract
Postglacial emergence curves are used to infer mantle rheology, delimit ice extent, and test models of the solid Earth response to changing ice and water loads. Such curves are rarely produced by direct dating of land emergence; rather, most rely on the presence of radiocarbon-datable organic material and inferences made between the age of sedimentary deposits and landforms indicative of former sea level. Here, we demonstrate a new approach, 10Be dating, to determine rates of postglacial land emergence in two different settings. In southern Greenland (Narsarsuaq/Igaliku), we date directly the exposure, as relative sea level fell, of gravel beaches and rocky outcrops allowing determination of rapid, post–Younger Dryas emergence. In western Greenland (Kangerlussuaq), we constrain Holocene isostatic response by dating the sequential stripping of terrace sediment driven by land-surface uplift, relative sea-level fall, and resulting fluvial incision. The technique we employ provides high temporal and elevation resolution important for quantifying rapid emergence immediately after deglaciation and less rapid uplift during the middle Holocene. 10Be-constrained emergence curves can improve knowledge of relative sea-level change by dating land emergence along rocky coasts, at elevations and locations where radiocarbon-datable sediments are not present, and without the lag time needed for organic material to accumulate.
Date Issued
2018-07-01
Date Acceptance
2018-01-11
Citation
Quaternary Research, 2018, 90 (1), pp.110-126
ISSN
0033-5894
Publisher
Cambridge University Press
Start Page
110
End Page
126
Journal / Book Title
Quaternary Research
Volume
90
Issue
1
Copyright Statement
© 2018 Cambridge University Press. This paper has been accepted for publication and will appear in a revised form, subsequent to peer-review and/or editorial input by Cambridge University Press.
Subjects
Science & Technology
Physical Sciences
Geography, Physical
Geosciences, Multidisciplinary
Physical Geography
Geology
Uplift
Isostasy
Glacier
Ice sheet
Emergence
Beach
Cosmogenic
Dating
RELATIVE SEA-LEVEL
LAURENTIDE ICE-SHEET
LAST GLACIAL MAXIMUM
COSMOGENIC BE-10
HOLOCENE HISTORY
ISOLATION BASINS
EAST GREENLAND
WEST GREENLAND
AREA
DEGLACIATION
0403 Geology
0406 Physical Geography and Environmental Geoscience
2101 Archaeology
Paleontology
Publication Status
Published
Date Publish Online
2018-04-12