The Ordovician Succession Adjacent to Hinlopenstretet, Ny Friesland, Spitsbergen

• Published in: American Museum Novitates
• Main Authors: Björn Kröger, Seth Finnegan, Franziska Franeck, Melanie J. Hopkins
• Format: Text
• Language: English
• Published: American Museum of Natural History 2017
• Subjects: Hinlopenstretet; Ny Friesland; Valhallfonna; Hinlopen Strait; Spitsbergen
• Online Access: https://doi.org/10.1206/3882.1

The Ordovician sections along the western shore of the Hinlopen Strait, Ny Friesland, Spitsbergen were discovered in the late 1960s and since then prompted numerous paleontological publications; several of these publications are now considered classical in the literature of paleontology of Ordovician trilobites and of Ordovician paleogeography and stratigraphy. Our 2016 expedition aimed at a major recollection and reappraisal of these classical sites. Here we provide a first high-resolution lithological description of the Kirtonryggen and Valhallfonna formations (Tremadocian—Darriwilian), which together comprise a thickness of 843 m, a revised bio-, and lithostratigraphy, and an interpretation of the depositional sequences. We find that the sedimentary succession is very similar to successions of eastern Laurentia; its Tremadocian and early Floian part is composed of predominantly peritidal dolostones and limestones characterized by ribbon carbonates, intraclastic conglomerates, microbial laminites, and stromatolites, and its late Floian to Darriwilian part is composed of fossil-rich, bioturbated, cherty mud-wackestone, skeletal grainstone and shale, with local siltstone and glauconitic horizons. The succession can be subdivided into five third-order depositional sequences, which are interpreted as representing the Sauk IIIB Supersequence known from elsewhere on the Laurentian platform.