New data on Upper Ordovician conodonts from theTrondheim Region, Central Norwegian Caledonides

Abstract

A small collection of Upper Ordovician (Early-Mid Katian) conodonts has been recovered from low-grade meta-limestones in the K\u00F6li Nappes of the Upper Allochthon of the Trondheim Region, central Norway. For the Snåsavatnet area and the western coast of the Frosta peninsula, these are the first reported conodonts. Conodonts that were obtained from the Svartsætra limestone of the Hølonda area confirm an Early Katian (Caradocian) age for the formation, in accordance with a previous study. The composition of the species and poor preservation of conodonts from the Snåsavatnet and Frosta areas do not permit a precise age assignment. However, the conodont faunas are most probably coeval with that of the Svartsætra limestone, even though the taxonomic composition of conodont assemblages from the latter locality is completely different. The limestones of the Snåsavatnet area (Snåsa Limestone) and the western coast of the Frosta peninsula (Risset limestone) yielded elements of the pelagic conodonts Ansellasp., Periodon grandis and Hamarodussp., which are characteristic of a wide variety of depositional environments including basinal and slope settings.