Carbonate sedimentation beneath the Antarctic Circumpolar Current ( Indian Ocean).
Calcium carbonate sedimentation beneath the Antarctic Circumpolar Current (ACC) was studied based on the analysis of four USNS Eltanin cores taken between 38 and 43o S latitude in the SE Indian Ocean sector of the Southern Ocean. Calcium carbonate content and planktonic foraminiferal fragmentation are used to determine a record of calcium carbonate sedimentation over the last 440 000 years. The fragmentation records are compared with a history of deep-water circulation within the ACC based on deep-sea benthonic foraminifera from these cores to determine if there is any relationship between carbonate dissolution and deep-water circulation conditions during the Late Quaternary. The benthonic foraminiferal faunas during interglacial times are similar to those presently found in the area, indicating that interglacial deep- water circulation was similar to present-day conditions. By contrast, the Melonis-Uvigerina assemblage indicates a water mass within the glacial ACC which was distinctly different from the present-day Circumpolar Deep Water. -from Current Antarctic Literature
