Palynology and dinoflagellate biostratigraphy of Deep Sea Drilling Project Leg 94, Sites 607 and 611, North Atlantic Ocean.

Abstract

Cores from DSDP Holes 607, 607A, 611, and 611C were sampled at about 1m intervals for study of palynomorphs and palynodebris types. At both the subtropical Site 607, W of the Azores (40o07'N), and the high-latitude Gardar Drift Site 611 (52o50'N), dinoflagellate cysts and pollen show cyclical variations in abundance, with peaks spaced 2-8m apart downcore. This variation appears to correspond to climatic fluctuations with periods of 50 000-200 000yr in the late Pliocene and Pleistocene, and to bottom sediment transport events or long-period climatic events during the late Miocene to early Pliocene. Well-preserved dinoflagellate cysts are present throughout the upper Miocene to Pleistocene sediments, but numbers of pollen and spores are too low to provide reliable biostratigraphic information. -from Author