Abstracts of the 32Nd Nordic Geological Winter

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Abstracts of the 32Nd Nordic Geological Winter

The Ediacaran succession and fauna of the Digermulen Peninsula, northern Norway J.O. Ebbestad1*, A.E.S. Högström2, S. Jensen3, G. Meinhold4, W.L. Taylor5, T. Palacios3, M. Høyberget6, L.K. Novis2 and Z. Ou2 1Museum of Evolution, Uppsala University, Norbyvägen 16, SE-752 36 Uppsala, SWEDEN (*[email protected]) 2Tromsø University Museum, UiT the Arctic University of Norway, Tromsø, N-9037, NOR- WAY 3Area de Paleontologia, Universidad de Extremadura, Avenida de Elvas s/n, Badajoz, 06006, SPAIN 4Geoscience Center, University of Göttingen, Goldschmidtstr. 3, Göttingen, 37077, GER- MANY 5Department of Geological Sciences, University of Cape Town, Private Bag X3, Rodenbosch, 7701, SOUTH AFRICA 6Rennesveien 14, Mandal, N-4513, NORWAY First discovered in the late 1980’s, the Digermulen Peninsula in Finnmark, northern Norway, is the only locality in Scandinavia with Ediacara-type fossils. The Edi- acaran to Lower Ordovician sedimentary succession here consists of over 3000 m of siliciclastic-rich deposits formed in a foreland basin marginal to Baltica. Since 2011, studies by the Digermulen Early Life Research Group have recorded significant new finds, promising to establish the site as a new key Ediacaran biota locality. TheEdi- acaran succession is close to 1000 m thick. It starts with interglacial sediments of the Nyborg Formation (tentatively earliest Ediacaran), followed by the glaciogenic diamic- tites of the Mortensnes Formation (∼60 m thick), probably representing the ∼582 Ma Gaskiers glaciation. Ediacara-type fossils occur in the Innerelva Member of the suc- ceeding Stáhpogiedde Formation. This is followed by the Lower Cambrian Breidvika Formation. The Ediacaran–Cambrian boundary is located within the Manndraperelva Member of the Stáhpogiedde Formation, identified by the trace fossil Treptichnus pe- dum, associated trilobed trace fossils and microfossils. The Ediacaran assemblage is dominated by discoidal fossils, the nomenclature of which is currently under study. The 2015 field season brought to light the first specimen of a multi-vaned Ediacara- type fossil, so far unidentified. In addition, well-preserved Hiemalora are found, and Palaeopascichnus occur near the base of the Innerelva Member. This makes them the oldest non-stromatolite macroscopic fossils in Scandinavia. Hitherto the Innerelva Member has not yielded microfossils. 1 View publication stats.

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