Open AccessGlacial deep water geometry: South Atlantic benthic foraminiferal Cd/Ca and δ 13 C evidence
Author(s) -
Oppo Delia W.,
Horowitz Michael
Publication year - 2000
Publication title -
paleoceanography
Language(s) - English
Resource type - Journals
eISSN - 1944-9186
pISSN - 0883-8305
DOI - 10.1029/1999pa000436
Subject(s) - benthic zone , geology , oceanography , glacial period , foraminifera , transect , antarctic bottom water , north atlantic deep water , water mass , deep water , deep sea , bottom water , antarctic intermediate water , paleontology
A depth transect of cores from 1268 to 3909 m water depth in the western South Atlantic are ideally situated to monitor the interocean exchange of deep water and variations in the relative strength of northern and southern sources of deep water production. Benthic foraminiferal Cd/Ca and δ 13 C data suggest that Glacial North Atlantic Intermediate Water (GNAIW) extended at least as far south as 28°S in the western South Atlantic. The core of nutrient‐depleted water was situated at ∼1500 m, above and below water masses with higher nutrient concentrations. When examined in conjunction with published paired Cd/Ca and δ 13 C from intermediate depth cores from other basins, it appears that the extent of GNAIW influence on the intermediate waters of the world's oceans was less than suggested previously. Differentiating among possible pathways for the glacial deep ocean (>3 km) requires a better understanding of the controls on Cd/Ca and δ 13 C values of benthic foraminifera.