Palynology of the Sinemurian/Pliensbachian boundary (Lower Jurassic) in the Wutach area, SW Germany: dinoflagellate cyst systematics, biostratigraphy and heterotrophic character of Liasidium variabile
published: Nov 1, 2009
ArtNo. ESP155025403003, Price: 29.00 €
A palynological study of the outcrop section at Aselfingen, Wutach area, SW Germany, has yielded well-preserved and relatively diverse dinoflagellate cyst assemblages from sediments of Late Sinemurian and Early Pliensbachian age. The encountered dinoflagellate cyst taxa are documented and their morphology, systematics and stratigraphical ranges are discussed. The precise correlation of the samples to chronozones and subzones and the continuous record of dinoflagellate cysts from all sampled beds in this section allow a high-resolution palynostratigraphical characterisation of the Sinemurian/Pliensbachian boundary. This was not possible in the recently ratified Global Boundary Stratigraphic Section and Point (GSSP) for the base of the Pliensbachian stage in Yorkshire, UK, because it was found to be devoid of dinoflagellate cysts. The study yielded new information on the stratigraphical ranges of some widely used index taxa such as Liasidium variabile, Mancodinium semitabulatum and Valvaeodinium armatum. The discovery of weakly fluorescing, brown-pigmented specimens of Liasidium variabile, together with evidence from previous studies, leads to the interpretation that these cysts may have been formed by a heterotrophic dinoflagellate.