Neogene to recent palynostratigraphy of circum-Arctic basins: results of ODP Leg 104, Norwegian Sea, Leg 105, Baffin Bay, and DSDP Site 611, Irminger Sea

Abstract

ODP drilling in the Norwegian Sea (Leg 104) and Baffin Bay (Leg 105, Site 645) provided the first continuous cores for study of Neogene to recent paleoclimatic changes in the circum-Arctic basins of the North Atlantic. Well preserved dinoflagellate cysts, acritarchs, pollen, and spores were found in most samples, and ranges of selected dinocysts can be correlated with zonations for DSDP Site 611 south of Iceland, eastern Canadian offshore wells, Labrador Sea Sites 646 and 647, North Pacific DSDP Leg 19 sites, and the Arctic Ocean. Four marine microplankton palynozones are defined, with boundaries corresponding to magnetostratigraphic or biochronological ages of about 9, 4.2, and 1.4 Ma. A succession of major paleoecological events is given for this microplankton stratigraphy. Pollen and spore assemblages in the western North Atlantic cores show corresponding palynofacies changes which are related to major shifts in climate, topography, and vegetation of the North American continent, Canadian Arctic Islands, and Greenland. -from Authors