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Title: The impact of the Neoglacial and other environmental changes on the raised beaches of Joinville Island, Antarctica
Abstract In order to reconstruct past environmental conditions along the north-eastern Antarctic Peninsula, we documented changes in grain size, grain roundness, onlap as seen in ground-penetrating radar reflection profiles and ice-rafted debris on a set of 36 raised beaches developed over the last ~7.7 ± 0.9 ka on Joinville Island. The most pronounced changes in beach character occur at ~2.7–3.0 ka. At this time, there appears to have been a reintroduction of less rounded material, the development of stratification within individual beach ridges, an introduction of seaweed and limpets to the beach deposits, a change in clast provenance (although slightly earlier than the change in cobble roundness) and a shallowing of the overall beach plain slope. Prolonged cooling associated with the Neoglacial period may have contributed to these changes, as the readvance of glaciers could have changed the provenance of the beach deposits and introduced more material, leading to the change in roundness of the beach cobbles and the overall slope of the beach plain. This study suggests that late Holocene environmental change left a measurable impact on the coastal zone of Antarctica.  more » « less
Award ID(s):
1644197
PAR ID:
10537566
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Cambridge
Date Published:
Journal Name:
Antarctic Science
Volume:
35
Issue:
6
ISSN:
0954-1020
Page Range / eLocation ID:
418 to 437
Subject(s) / Keyword(s):
Climate, coastlines, glacial isostatic adjustment, Holocene, sea level, Weddell Sea
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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