Upper Ordovician graptolites and biostratigraphy of the Röstånga 1 core, Scania, S. Sweden

A core drilling at Röstånga in 1997, referred to as Röstånga 1, penetrated a significant portion of the Upper Ordovician-Lower Silurian succession in this classical Lower Palaeozoic outcrop area in Wcentral Scania. In descending order the Upper Ordovician of the core embraces the following units (stratigraphic thickness in parenthesis): Lindegård Mudstone (27.8 m.), Fjäcka Shale (13.6 m), Mossen Formation (0.6 m), Skagen Formation (0.8 m.), and Sularp Formation (19.9 m+). Graptolites are described from the Lindegård Mudstone, the Fjäcka Shale, and the Mossen Formation. The graptolites are classified into 12 taxa, among which 9 are identified to species. Graptolites are very rare in the Mossen Formation, which has yielded only two specimens of Pseudoclimacograptus scharenbergi. The Fjäcka Shale yielded a fairly diverse graptolite fauna, indicative of the Pleurograptus linearis Zone. This zone is succeeded by the Dicellograptus complanatus Zone, with the zonal index appearing in the lower part of the Lindegård Mudstone immediately above graptolites indicative of the P. linearis Zone. No graptolites were recovered from the Skagen Formation and the Sularp Formation.