GEOSCAN, résultats de la recherche


TitreNeoglacial ice expansion and late Holocene cold-based ice cap dynamics on Cumberland Peninsula, Baffin Island, Arctic Canada
AuteurMargreth, A; Dyke, A S; Gosse, J C; Telka, A M
SourceQuaternary Science Reviews vol. 91, 2014 p. 242-256,
LiensSupplement (PDF 1.05 MB)
Séries alt.Secteur des sciences de la Terre, Contribution externe 20140119
Documentpublication en série
Mediapapier; en ligne; numérique
SNRC16E; 16L; 25H; 26I
Lat/Long OENS-65.0000 -63.0000 67.0000 65.0000
Sujetsdatations au radiocarbone; fossiles; Holocène; glace marine; glace; fluctuations climatiques; flore; végétation; carottes; géochronologie; paléontologie; Quaternaire
ProgrammeGisements polymétalliques - Péninsule Cumberland (île de Baffin, Nunavut), GEM : La géocartographie de l'énergie et des minéraux
Résumé(disponible en anglais seulement)
Radiocarbon dating of fossil flora and fauna collected along receding cold-based ice caps and cold-based sections of polythermal glaciers on Cumberland Peninsula reveal insights into Neoglacial ice expansion and late Holocene ice dynamics. The taphonomic advantages of subfossilized moss were exploited to precisely document regional expansions of ice caps through the late Holocene. When compared with climate proxies and records of volcanic eruptions, the moss radiocarbon age distributions indicate i) onset of Neoglaciation shortly after 5 ka, concomitant with increased sea ice cover, ii) intensification of ice expansion between 1.9 and 1.1 ka, followed by halt of ice growth, or ice recession during the Medieval Warm Period, and iii) renewed ice expansion after 0.8 ka, in response to cooling related to a combination of large volcanic eruptions and low solar activity. Overall, the observations support a model of near-instantaneous glacial response to regional climate controls and that these responses were synchronous throughout eastern Canadian Arctic and possibly eastern Greenland.