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Late glacial fluctuations of the Laurentide Ice Sheet in the White Mountains of Maine and New Hampshire, U.S.A.

Published online by Cambridge University Press:  20 January 2017

Gordon R.M. Bromley ,
Brenda L. Hall ,
Woodrow B. Thompson ,
Michael R. Kaplan ,
Juan Luis Garcia  and
Joerg M. Schaefer
Gordon R.M. Bromley*
Affiliation:
School of Earth & Climate Sciences and the Climate Change Institute, Edward T. Bryand Global Sciences Center University of Maine, Orono, ME 04469-5790, USA
Brenda L. Hall
Affiliation:
School of Earth & Climate Sciences and the Climate Change Institute, Edward T. Bryand Global Sciences Center University of Maine, Orono, ME 04469-5790, USA
Woodrow B. Thompson
Affiliation:
Maine Geological Survey, 93 State House Station, Augusta, ME 04333-0093, USA
Michael R. Kaplan
Affiliation:
Lamont-Doherty Earth Observatory, Geochemistry, Route 9W, Palisades, NY 10964, USA
Juan Luis Garcia
Affiliation:
School of Earth & Climate Sciences and the Climate Change Institute, Edward T. Bryand Global Sciences Center University of Maine, Orono, ME 04469-5790, USA Instituto de Geografia, Pontificia Universidad Catolica de Chile, Avenida Vicuna Mackenna 4860, Santiago 782-0436, Chile
Joerg M. Schaefer
Affiliation:
Lamont-Doherty Earth Observatory, Geochemistry, Route 9W, Palisades, NY 10964, USA
*
*Corresponding author. Fax: + 1 207 581 1203. E-mail address:[email protected] (G.R.M. Bromley).
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Abstract

Prominent moraines deposited by the Laurentide Ice Sheet in northern New England document readvances, or stillstands, of the ice margin during overall deglaciation. However, until now, the paucity of direct chronologies over much of the region has precluded meaningful assessment of the mechanisms that drove these events, or of the complex relationships between ice-sheet dynamics and climate. As a step towards addressing this problem, we present a cosmogenic 10Be surface-exposure chronology from the Androscoggin moraine complex, located in the White Mountains of western Maine and northern New Hampshire, as well as four recalculated ages from the nearby Littleton–Bethlehem moraine. Seven internally consistent 10Be ages from the Androscoggin terminal moraines indicate that advance culminated ~ 13.2 ± 0.8 ka, in close agreement with the mean age of the neighboring Littleton–Bethlehem complex. Together, these two datasets indicate stabilization or advance of the ice-sheet margin in northern New England, at ~ 14–13 ka, during the Allerød/Greenland Interstadial I.

Keywords

Laurentide Ice SheetNew EnglandDeglaciationLate glacialAllerødReadvance
Type
Original Articles
Information
Quaternary Research , Volume 83 , Issue 3 , May 2015 , pp. 522 - 530
Copyright
University of Washington

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