Palynostratigraphy and palaeoenvironments of the lower to middle jurassic bagå formation of bornholm, denmark

Abstract

Abstract The Baga Formation includes up to approximately 400 m of paralic, lacustrine and alluvial deposits without marine macrofossils. Detailed palynological and sedimentological studies have been undertaken of all available cored boreholes and exposures of the formation. A total of 150 palynological samples were examined from partially overlapping sections amounting to a total of ca. 650 m. The palynomorphs recovered, some of which are stratigraphically important, comprise very diverse and well‐preserved assemblages from which 130 species including 67 spore, 32 pollen and 31 microplankton species are identified. The assemblages are subdivided into the Chasmatosporites, Spheripollenites‐Leptolepidites and Callialasporites‐Perinopollenites miospore zones and the Mendicodinium reticulatum, Luehndea spinosa and Nannoceratopsis gracilis dinoflagellate cyst zones. Three of these, the Chasmatosporites, Callialasporites ‐Perinopollenites and Mendicodinium reticulatum zones, are newly proposed here. The Baga Fo...