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

drilling at Rostanga in 1997, referred to as Rostanga 1, penetrated a significant portion of the Upper Ordovician-Lower Silurian succession in this classical Lower Palaeozoic outcrop area in W-central Scania. In descending order the Upper Ordovician of the core embraces the following units (stratigraphic thickness in parenthesis): Lindegard Mudstone (27.8 m), Fjacka Shale (13.6 m), Mossen Formation (0.6 m), Skagen Formation (0.8 m), and Sularp Formation (19.9 m+). Grapiolites are described from the Lindegard Mudstone, the Fjacka 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 Fjacka 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 LindegArd Mudstone immediately above graptolites indicative of the P. linearis Zone. No graptolites were recovered from the Skagen Formation and the Sularp Formation.