Dinoflagellate cyst assemblage 1 (DA1, from 2632 to 2618 m, Fig. 7p) contains high proportions of typically open marine and hence normal marine salinity associated Achomosphaera/Spiniferites spp. , undifferentiated chorate cysts and Areoligera/Glaphyrocysta spp. DA1 also contains on average 5% peridinoid cysts including Deflandrea spp. regarded as a coastal/neritic taxon indicating high productivity and nutrient availability (Brinkhuis, 1994; Pross and Brinkhuis, 2005). These characteristics indicate that a somewhat restricted but fully marine shelf environment was present before the onset of the CIE in the central North Sea, with availability of nutrients indicated by the presence of Deflandrea spp.
Dinoflagellate cyst assemblage 1 (DA1
from 2632 to 2618 m
m
DA1
peridinoid cysts
on average 5%
%