Deep-water circulation was reconstructed for the late neogene by comparing carbon isotopic records of benthic foraminifera from the North Atlantic (NA), Southern Ocean (SO), and deep Pacific Basins. The history of NA intermediate water was studied using delta (super 13) C at Ocean Drilling Program (ODP) Site 982. Production of Glacial North Atlantic Intermediate Water (GNAIW) was enhanced during glacial periods of the late Pleistocene whereas production of lower North Atlantic Deep Water (NADW) was much reduced. During terminations, production of GNAIW ceased briefly until upper-NADW production resumed under full interglacial conditions. The magnitude of benthic delta (super 13) C minima, ice-rafted debris maxima at Site 982, and glacial suppression of NADW may be related to the spatial and seasonal extent of sea ice in the Nordic Seas. The history of deep-water circulation in the Atlantic sector of the SO was examined using a delta (super 13) C record from ODP Site 1090 in the South Atlantic (SA). At 1.55 Ma, glacial delta (super 13) C values in the SA sector of the SO became significantly lower than those in the deep Pacific, establishing a pattern that persisted throughout the late Pleistocene. Lower delta (super 13) C values in the SO may have resulted from expansion of sea ice and reduced ventilation of deep-water during glacial periods. Accompanying this change in SO deep-water circulation was enhanced interhemispheric coupling between the NA and SA. (modif. auth. abstr.)

West: -110.3111 East: 8.5359 North: 57.3100 South: -42.5449

Expedition: 138

Site: 138-849

Expedition: 162

Site: 162-982

Expedition: 177

Site: 177-1090

Provider: SEDIS Publication Catalogue

Data set link: http://sedis.iodp.org/pub-catalogue/index.php?id=2005-056721 (c.f. for more detailed metadata)

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