Zurich Open Repository and Archive University of Zurich Main Library Strickhofstrasse 39 CH-8057 Zurich www.zora.uzh.ch Year: 2017 New late Smithian (Early Triassic) ammonoids from the Lusitaniadalen Member, Vikinghogda Formation, Svalbard Piazza, Veronica ; Hammer, Øyvind ; Jattiot, Romain Abstract: A single carbonate concretion from the uppermost Lusitaniadalen Member (‘Fish Niveau’, Vikinghøgda Formation) at Stensiöfjellet, Spitsbergen, contains a fairly rich assemblage of late Smithian (Early Triassic, Olenekian) ammonoids. The main species identified are Wasatchites tridentinus Spath, 1934, Wasatchites cf. distractus (Waagen, 1895), Anasibirites kingianus (Waagen, 1895), Arctoprionites nodosus (Frebold, 1930), Arctoprionites resseri (Mathews, 1929) and Xenoceltites subevolutus Spath, 1930. Two taxa are here discussed: Prionitid sp. and Arctoceras erebori sp. nov. The assemblage provides new information about the Early Triassic biostratigraphy and palaeogeography of the Boreal Realm. The composition of the Spitsbergen fauna is in good agreement with other assemblages within and outside the Boreal Realm and essentially comprises cosmopolitan taxa. Only Arctoceras erebori sp. nov. and Prionitid sp. are as yet restricted to Spitsbergen. The newly reported occurrence of low paleolatitude taxa from Spitsbergen strengthens the cosmopolitan distribution of ammonoids during late Smithian time, thus improving existing correlation. DOI: https://doi.org/10.17850/njg97-2-03 Posted at the Zurich Open Repository and Archive, University of Zurich ZORA URL: https://doi.org/10.5167/uzh-139383 Journal Article Published Version The following work is licensed under a Creative Commons: Attribution 4.0 International (CC BY 4.0) License. Originally published at: Piazza, Veronica; Hammer, Øyvind; Jattiot, Romain (2017). New late Smithian (Early Triassic) am- monoids from the Lusitaniadalen Member, Vikinghogda Formation, Svalbard. Norwegian Journal of Geology, 97(2):105-117. DOI: https://doi.org/10.17850/njg97-2-03 NORWEGIAN JOURNAL OF GEOLOGY Vol 97 Nr. 2 https://dx.doi.org/10.17850/njg97-2-03 New late Smithian (Early Triassic) ammonoids from the Lusitaniadalen Member, Vikinghøgda Formation, Svalbard Veronica Piazza1, Øyvind Hammer2 & Romain Jattiot3,4 1Museum für Naturkunde, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, Invalidenstr. 43, 10115 Berlin, Germany. 2Naturhistorisk Museum, Universitetet i Oslo, P.O. Box 1172 Blindern, 0318 Oslo, Norway. 3Paläontologisches Institut der Universität Zürich, Karl Schmid-Strasse 4, 8006, Zürich, Switzerland. 4UMR CNRS 6282 Biogeosciences, Université de Bourgogne Franche-Comté, 6 Boulevard Gabriel, 21000, Dijon, France. E-mail corresponding author (Veronica Piazza): [email protected] A single carbonate concretion from the uppermost Lusitaniadalen Member (‘Fish Niveau’, Vikinghøgda Formation) at Stensiöfjellet, Spitsbergen, contains a fairly rich assemblage of late Smithian (Early Triassic, Olenekian) ammonoids. The main species identified are Wasatchites tridentinus Spath, 1934, Wasatchites cf. distractus (Waagen, 1895), Anasibirites kingianus (Waagen, 1895), Arctoprionites nodosus (Frebold, 1930), Arctoprionites resseri (Mathews, 1929) and Xenoceltites subevolutus Spath, 1930. Two taxa are here discussed: Prionitid sp. and Arctoceras erebori sp. nov. The assemblage provides new information about the Early Triassic biostratigraphy and palaeogeography of the Boreal Realm. The composition of the Spitsbergen fauna is in good agreement with other assemblages within and outside the Boreal Realm and essentially comprises cosmopolitan taxa. Only Arctoceras erebori sp. nov. and Prionitid sp. are as yet restricted to Spitsbergen. The newly reported occurrence of low paleolatitude taxa from Spitsbergen strengthens the cosmopolitan distribution of ammonoids during late Smithian time, thus improving existing correlation. Keywords: Ammonoid biostratigraphy, Tardus Zone, Smithian, Prionitidae, Svalbard, Boreal Realm. Received 4. May 2017 / Accepted 21. June 2017 / Published online 7. August 2017 Introduction Triassic palaeogeographic setting A growing interest is focused on the usefulness of Early During the Mesozoic, the Svalbardian faunas belonged, in to Middle Triassic ammonoids of the Boreal Realm as a broader palaeobiogeographic perspective, to the Boreal high-resolution biostratigraphic markers, which in part Realm, which also included present-day Greenland, benefit the increased petroleum exploration activity in Arctic Canada (Sverdrup Basin) and Russia (Siberia). the region and its need for accurate biochronological These localities (Fig. 1) were located along the northern correlation. A revision of ammonoid taxonomy, bio- margin of Pangaea, making intra-Boreal correlations stratigraphy and palaeobiogeography of the Boreal possible, while British Columbia (Canada) was located Triassic is therefore required. The present paper provides at mid-palaeolatitudes (Dagys & Weitschat, 1993a; Tozer, new interpretations of a late Smithian fauna from 1994; Vigran et al., 2014). Spitsbergen, and a new taxon is presented. Piazza, V., Hammer, Ø. & Jattiot. R. 2017: New late Smithian (Early Triassic) ammonoids from the Lusitaniadalen Member, Vikinghøgda Formation. Norwegian Journal of Geology 97, 105–117. https://dx.doi.org/10.17850/njg97-2-03. © Copyright the authors. This work is licensed under a Creative Commons Attribution 4.0 International License. 105 Svalbard are closely related to the faunas of the Sverdrup of the Sverdrup the faunas to related closely are Svalbard of faunas Smithian late The 2010). al., et (Brühwiler 1). fig. 2010, al., et Brühwiler from (modified is shown stars) (black localities important asother aswell star) 1. Figure and xenoceltitids (e.g., (e.g., xenoceltitids and prionitids cosmopolitan by characterised is and Realm, the Boreal in Smithian Zone defines the late Tardus The 1. Table in shown is of of Svalbard the Smithian divisions biostratigraphic ammonoid overviewAn of important the most 1993a). Weitschat, Dagys 1989; & &Dagys, Weitschat 1978; &Lehmann, Weitschat (e.g., Weitschat 1973)and 1970, (e.g., Korčinskaja by provided were contributions Subsequent zonation. a modern ammonoid at attempt an Zone in Tardus the upper Zone and Romunderi thelower into Svalbard in the Smithian subdivided (1968) who & Parker Tozer was it However, (1930). Frebold 1934)and (1921, Spath by studied originally were fossils Smithian 1877). Öberg, (e.g., 140years than more been for known have fossils Triassic Svalbardian biostratigraphy Smithian &Dagys (1989). Weitschat by proposed was province of a Svalbardian the establishment affiliations, Based these intermediate on constant. not affinities were such although both ofaffinities to these provinces, presenting in between, was somewhat located Svalbard differences of assemblages. taxonomic the ammonoid to according provinces (Siberian) eastern Basin)and (Sverdrup western Boreal Realm be can into divided Triassic Early The 2006). al., et Brayard 1982; (Tozer, high endemism 2008)and Weitschat, 2005; Bucher, & Hammer (e.g., intraspecific variation significant (= local) diversity, alpha low by mainly characterised were faunas ammonoid Triassic BorealEarly 106 V. Piazza et al. Piazza et V. Early Triassic palaeogeographic setting. Spitsbergen (red (red Spitsbergen setting. palaeogeographic Triassic Early Xenoceltites Spath, 1930); 1930); Spath, Table 1. Review of the most important changes in ammonoid biostratigraphic zonation of the Smithian in Svalbard and correlations with the other Boreal regions.. High- Mid- palaeolatitude palaeolatitude Siberia Spitsbergen (Boreal Standard)/ British lithostratigraphy Svalbard Sverdrup Basin Columbia (Hounslow et al., 2008) (Arctic Canada) West Central– Wiman (1910) Spath Frebold (1930) Korčinskaja Lock et al. (1978) (Korčinskaja, Dagys & Dagys & Tozer East (1921) (1973) 1986)* Weitschat Weitschat (1994) (1993a) (1993a) Lower Arctoceras Arctoceras Wasatchites Wasatchites Wasatchites Wasatchites Wasatchites Posidonomya horizon horizon tardus tardus tardus tardus tardus beds Fish-Niveau Goniodiscus/ Anasibirites Arctoceras Euflemingites Arctoceras Euflemingites Lepiskites Euflemingites Anasibirites blomstrandi E. romunderi horizon blomstrandi romunderi romunderi kolymensis romunderi (Smithian) horizon Lower Olenekian Vikinghøgda Fm.) Vikinghøgda Tvillingodden Fm.) Tvillingodden Iskletten Mbr. (lower (lower Mbr. Iskletten Hedenstroemia Lusitaniadalen Mbr. (upper (upper Mbr. Lusitaniadalen hedenstroemi *As mentioned in Weitschat & Dagys (1989). NORWEGIAN JOURNAL OF GEOLOGY New late Smithian (Early Triassic) ammonoids from the Lusitaniadalen Member, Vikinghøgda Formation, Svalbard 107 Basin (Weitschat & Lehmann, 1978). The Boreal Tardus The occurrence of the arctoceratid genus Arctoceras Zone can be correlated with the stratigraphic units Hyatt, 1900 in Svalbard has long been controversial containing Wasatchites Mathews, 1929, Anasibirites in the literature. According to various authors (e.g., Mojsisovics, 1896 and Xenoceltites in many Tethyan Kummel, 1961; Tozer & Parker, 1968), it ranges through localities (e.g., South China: Brayard & Bucher, 2008; the whole of the Smithian in Svalbard. It was designated Primorye, Russia: Shigeta & Zakharov, 2009; Tulong, as an index taxon by Korčinskaja (e.g., 1986) to define Tibet: Brühwiler et al., 2010; Oman: Brühwiler et al., a new zonation, which was, however, not confirmed by 2012a; Salt Range, Pakistan: Brühwiler et al., 2012b; Weitschat & Dagys (1989). Instead,