Cretaceous palynofloras from southern Scandinavia

Sammanfattning: A palynological investigation of Cretaceous sequences from Höllviken 2, Svedala 1 and Norrevång 1 wells of Scania, Southern Sweden, and from the Arnager Greensand-Arnager Limestone transition on the island of Bornholm, Denmark, was conducted. Well preserved palynofloras were found in strata consisting of shaly mudstones, glauconitic sandstones (greensand) and limestone. A total of 98 palynomorph taxa were identified, including the new taxon Cingutriletes scanicus. A pollen-spore zonation for the area consisting of four zones (A, B, C and D) is presented. A Berriasian to Albian age is suggested for the shaly mudstones and the lower part of the greensand. The abundance of the pollen genus Rugubivesiculites in the upper part of the greensand indicates that these beds are of Cenomanian age. Palynofacies analysis suggests that the sediments of Berriasian-Valanginian age (shaly mudstones) were deposited in a continental paleoenvironment, while a coastal environment prevailed during the deposition of the basal part of the greensand. The upper part of the greensand was laid down in deeper water. Rising sea level in the late Cenomanian to Turonian interval is considered to be the cause of the interruption of deposition, leading to the development of a hardground-phosphoritic bed at the greensand-limestone transition. During the earliest Cretaceous, the flora was dominated by gymnosperms (predominantly cycads), while ferns were predominant during the Hauterivian to Aptian. During the late Aptian to early Albian, gymnosperms (mainly conifers) slightly dominated the ferns.