Ice rafted debris of ODP Holes 104-642B and 104-644A in the Vøring Plateau

These glacials indicate substantially larger Antarctic ice volumes than at present. The glacial episode at 5 Ma is correlated with the upper evaporite sequence of the Messinian salinity crisis in the Mediterranean. The Norwegian Sea was a net exporter of deep-water during most of the last 6 Myr.

Periods of carbonate dissolution lasting several 100 kyr indicate intervals of reduced ventilation and a more stable water column in the Norwegian Sea in both the late Miocene — Pliocene and the early Quaternary. There is no clear evidence for reduced deep-water formation during the upper Messinian event. High-frequency variation in δ 13C indicates that changes in deep-water ventilation rate were coupled with orbital forcing.

While the ventilation and deep-water chemistry of the Norwegian Sea has varied during the late Neogene, the δ 18O results indicate that Norwegian Sea deep-waters were denser and colder than those of the Atlantic during major portions of the last 6 Myr.