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Acritarchs from the Duolbagáisá Formation (Cambrian Series 2, Miaolingian) on the Digermulen Peninsula, Finnmark, Arctic Norway: towards a high-resolution Cambrian chronostratigraphy

Published online by Cambridge University Press:  24 April 2020

Teodoro Palacios*
Affiliation:
Área de Paleontología, Facultad de Ciencias, Universidad de Extremadura, Avenida de Física s/n, 06006Badajoz, Spain
Anette E. S. Högström
Affiliation:
Arctic University Museum of Norway, UiT the Arctic University of Norway, 9037Tromsø, Norway
Jan Ove R. Ebbestad
Affiliation:
Museum of Evolution, Uppsala University, Norbyvägen 16, 752 36Uppsala, Sweden
Heda Agić
Affiliation:
Department of Earth Sciences, Uppsala University, 752 36Uppsala, Sweden Department of Earth Science, University of California at Santa Barbara, Santa Barbara, CA93106, USA
Magne Høyberget
Affiliation:
Magne Høyberget, Rennesveien 14, 4513Mandal, Norway
Sören Jensen
Affiliation:
Área de Paleontología, Facultad de Ciencias, Universidad de Extremadura, Avenida de Física s/n, 06006Badajoz, Spain
Guido Meinhold
Affiliation:
Department of Sedimentology & Environmental Geology, Geoscience Centre, University of Göttingen, Goldschmidtstraße 3, 37077Göttingen, Germany School of Geography, Geology and the Environment, Keele University, Keele, Staffordshire, ST5 5BG, UK
Wendy L. Taylor
Affiliation:
Department of Geological Sciences, University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa
*
Author for correspondence: Teodoro Palacios, Email: medrano@unex.es

Abstract

New information on acritarchs from the Duolbagáisá Formation, Digermulen Peninsula, Arctic Norway, enable recognition of the three Cambrian Series 2 acritarch-based zones: the Skiagia ornataFimbriaglomerella membranacea, Heliosphaeridium dissimilareSkiagia ciliosa and Volkovia dentiferaLiepaina plana Assemblage zones. Acritarchs of the Skiagia ornataFimbriaglomerella membranacea Zone (Cambrian Stage 3) appear near the base of the unit, close to an undetermined trilobite. In the Upper Member of the Duolbagáisá Formation, in levels with Kjerulfia n. sp. and Elliptocephala n. sp., appears an assemblage with abundant Skiagia ciliosa, indicative of the Heliosphaeridium dissimilareSkiagia ciliosa Zone. A few metres higher appear Liepaina plana, Heliosphaeridium notatum and Retisphaeridium dichamerum, which indicate the Volkovia dentiferaLiepaina plana Zone (Cambrian Stage 4). The transition between the Duolbagáisá Formation and the overlying Kistedalen Formation is marked by the appearance of Comasphaeridium longispinosum, Multiplicisphaeridium llynense and Eliasum llaniscum, diagnostic of the Miaolingian Series. This coincides with the disappearance of Skiagia; occurrences of Skiagia in Miaolingian strata consist of reworked material related to the Hawke Bay regression at the Cambrian Stage 4–Wuliuan transition. The absence of Skiagia in higher levels of the Duolbagáisá Formation and Kistedalen Formation suggests that no unconformity formed during the Hawke Bay regression in this area. The chronostratigraphical significance of the Skiagia ornataFimbriaglomerella membranacea, Heliosphaeridium dissimilareSkiagia ciliosa and Volkovia dentiferaLiepaina plana zones is critically analysed. Correlation of the Duolbagáisá Formation with peri-Gondwanan terrains of Avalonia and Iberia is established. The Digermulen Peninsula has great potential as a reference section for establishing a Cambrian chronostratigraphy based on acritarchs.

Type
Original Article
Copyright
© Cambridge University Press 2020

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