Sedimentation rates and geochemical analysis of surface sediments from the South Atlantic

• Main Authors: Nürnberg, Christine Caroline, Bohrmann, Gerhard, Frank, Martin, Schlüter, Michael
• Format: Dataset
• Language: English
• Published: PANGAEA 1997
• Subjects: Agulhas Basin; Agulhas Ridge; Antarctic Peninsula; ANT-IX/2; ANT-IX/3; ANT-IX/4; ANT-V/4; ANT-VI/3; ANT-VIII/3; ANT-X/4; ANT-X/5; ANT-X/6; ANT-XI/2; Atka Bay; Atlantic Indik Ridge; Atlantic Ridge; AWI_Paleo; Barents Sea; Camp Norway; Cape Basin; CTD/Rosette; CTD-RO; Eastern Weddell Sea; Southern Ocean; Falkland Islands; Filchner Trough; Giant box corer; Giant gravity corer AWI; GKG; Gravity corer (Kiel type); GSL; Halley Bay; Indian-Antarctic Ridge; Islas Orcadas; Kapp Norvegia; KL; Lazarev Sea; Lyddan Island; Maud Rise; Meteor Rise; MG; MIC; MiniCorer; MUC; Multiboxcorer; MultiCorer; Paleoenvironmental Reconstructions from Marine Sediments @ AWI; Piston corer (BGR type); Polarstern; PS10; Antarctic; The Antarctic; Weddell Sea; Norway; Indian; Weddell; Lazarev; Atka; Orcadas; Antarc*; Sea ice
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.723566; https://doi.org/10.1594/PANGAEA.723566

Extensive investigations of sedimentary barium were performed in the southern South Atlantic in order to assess the reliability of the barium signal in Antarctic sediments as a proxy for paleoproductivity. Maximum accumulation rates of excess barium were calculated for the Antarctic zone south of the polar front where silica accumulates at high rates. The correspondence between barium and opal supports the applicability of barium as a proxy for productivity. Within the Antarctic zone north of today's average sea ice maximum, interglacial vertical rain rates of excess barium are high, with a maximum occurring during the last deglaciation and early Holocene and during oxygen isotope chronozone 5.5. During these periods, the maximum silica accumulation was supposedly located south of the polar front. Glacial paleoproductivity, instead, was low within the Antarctic zone. North of the polar front, significantly higher barium accumulation occurs during glacial times. The vertical rain rates, however, are as high as in the glacial Antarctic zone. Therefore there was no evidence for an increased productivity in the glacial Southern Ocean.