Preboreal onset of Norwegian cold-water coral growth beyond the Arctic Circle revealed by radiocarbon and U-series dating and neodymium isotopes

Beitrag in einer Fachzeitschrift
(Originalarbeit)


Details zur Publikation

Autor(en): López Correa M, Montagna P, Joseph N, Rüggeberg A, Fietzke J, Flögel S, Dorschel B, Goldstein S, Wheeler A, Freiwald A
Zeitschrift: Quaternary Science Reviews
Verlag: Elsevier
Jahr der Veröffentlichung: 2012
Band: 34
Seitenbereich: 24-43
ISSN: 0277-3791
Sprache: Englisch


Abstract


Cold-water coral mounds of Lophelia pertusa are widespread across the Scandinavian shelf, which was completely ice-covered during the Last Glacial Maximum between 22 to 18ka BP. Rapid deglacial meltdown of the Fennoscandian inland ice and the retreat of its ice-streams freed most of the shelf of ice by ~15ka BP. However, cold-water coral growth commenced only after the Pleistocene-Holocene transition at 11.65ka BP, when modern-like climatic patterns and oceanographic conditions were established. A tight climatic coupling has been constrained with U-series ages. Coupled 14C ages provide local reservoir ages from various gravity cores in a fjord-setting in Stjernsund at 70°N and on the open shelf in Trænadjupet at 66°N. Reinvestigation of earlier 14C coral chronologies suggests that coral ecosystems widely established themselves across the entire 3000km long Scandinavian shelf prior to ~10ka BP. The earliest occurrence of Madrepora oculata at ~2.4ka BP suggests a late Holocene colonization of the Norwegian shelf, which is linked to a prominent mound growth hiatus in Trænadjupet (64°N). Mound growth rates near the northern biogeographic boundary of L.pertusa with up to ~614cmka -1 during certain growth periods are much higher than the previously reported fastest rates of ~220cmka -1 from the Irish margin. Contemporaneous rapid fjordbasin sedimentation is slower with ~63cmka -1. Matrix 14C ages overlap with coral 14C ages from the same horizon. This indicates rapid framework construction and efficient trapping of background sediment. Hiatuses are frequent in on-mound sediments and only short periods of coral growth are recorded. Coupled Δ 14C and ε Nd values indicate a persistent Holocene inflow of the North Atlantic Current in Stjernsund, but also deglacial meltwater mixing during the early Holocene prior to ~9.5ka BP. Reservoir ages are overall close to the surface marine reservoir age, but ΔR is highly localized. © 2011 Elsevier Ltd.



FAU-Autoren / FAU-Herausgeber

López Correa, Matthias
Lehrstuhl für Paläoumwelt


Autor(en) der externen Einrichtung(en)
Christian-Albrechts-Universität zu Kiel


Zitierweisen

APA:
López Correa, M., Montagna, P., Joseph, N., Rüggeberg, A., Fietzke, J., Flögel, S.,... Freiwald, A. (2012). Preboreal onset of Norwegian cold-water coral growth beyond the Arctic Circle revealed by radiocarbon and U-series dating and neodymium isotopes. Quaternary Science Reviews, 34, 24-43. https://dx.doi.org/10.1016/j.quascirev.2011.12.005

MLA:
López Correa, Matthias, et al. "Preboreal onset of Norwegian cold-water coral growth beyond the Arctic Circle revealed by radiocarbon and U-series dating and neodymium isotopes." Quaternary Science Reviews 34 (2012): 24-43.

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