The resolution of a planktonic foraminifer Cenozoic biostratigraphy in the Greenland Sea and in the Arctic Ocean is quite low, because of the scarcity of calcareous microfossils and the low diversity of assemblages. The Neogloboquadrina pachyderma sin. Zone spans the entire Quaternary, whereas the Neogloboquadrina atlantica Superzone occupies the Pliocene and parts of the upper Miocene. Biogenic ice-rafted debris such as Inoceramus-prisms, indicative of glacial conditions, are first documented during the late Pliocene at the Fram Strait sites and at the Yermak Plateau. Conversely, brief warm-temperate to subtropical surface-water ingressions, documented by the occurrence of single specimens of Menardella menardii, M. Limbata, Globigerinoides ruber, Gls. conglobatus, Gls. Extremus, Gls. trilobus, Globigerinella aequilateralis, Sphaeroidinellopsis sp. juv., aff. S. Paenedehiscens, and Dentoglobigerina altispira are observed locally at the Yermak Plateau in the upper Pliocene sequence. Surface-water exchange to the north is documented by the occurrence of the Pacific planktonic foraminifer Neogloboquadrina asanoi in upper Pliocene sediments at the Fram Strait. Rare occurrences of planktonic foraminifers in Miocene and Paleogene sediments prevent the construction of a zonation.
Date of initial receipt: 14 July 1995
Date of acceptance: 1 December 1995
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