The drilling on Leg 151 provided the first sections that allow studies beyond isotope Stage 6 in the Fram Strait/Yermak Plateau area, thereby enabling insight into paleoenvironmental evolution prior to the last glacial cycle. The upper parts of Holes 909B and 912A were analyzed for their ice-rafted detritus (IRD) and foraminiferal contents and stable isotope compositions to obtain a relatively high-resolution record of the paleoenvironmental evolution during the last 400 k.y. in the region. The main features are similar to the records from the Fram Strait and the Yermak Plateau. Earlier glaciations (isotope Stages 6-12) were more severe than the last one. The content of foraminifers through time indicates a trend toward more open water, with a higher production through the two last glacial/interglacial cycles. Seasonal open-water conditions with a high foraminifer production occurred through all the glacial periods, indicating that the surface circulation of the Nordic Seas in glacial stages plays an important role in the growth and decay of high-latitude ice sheets, bringing moisture and heat northward during the glacials. Deep-water formation seems to be continuous in the Nordic Seas through most of the time period presented in this study. There was an apparent change in the style of glaciation in the earlier parts of the Brunhes Chron with the emergence of more strongly developed IRD peaks than before. Glacial activity also is an important element in the Matuyama Chron in the European Arctic.
Date of initial receipt: 7 July 1995
Date of acceptance: 30 December 1995
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