Direct stratigraphic correlation of the Vercors carbonate platform in SE France with the Barremian stratotype by means of dinoflagellate cysts

Abstract

Several spot samples from selected intervals in the Barremian-lower Aptian development of the Vercors Plateau (SE France) at the Pas de Berrieves, Montagnette and the Archiane valley were examined for their dinoflagellate cyst content. Using qualitative data, a direct correlation with stratigraphic occurrences of dinoflagellate cyst in the Barremian stratotype in the adjacent Vocontian Basin is established. Based on the concurrent presences of the diagnostic species Pseudoceratium retusum, Cerbia tabulata and Odontochitina operculata , a late Barremian age for these spot samples has been inferred. This assessment is not in accordance with the previously interpreted early Barremian age for the sediments at these localities. This discrepancy might be owing to a lack of ammonite information from the middle part of the Barremian stratotype section and the resulting poorly defined lower-upper Barremian boundary.