_version_ 1867169096358952960
author Anderson, Linda Davis
Delaney, Margaret Lois
author_facet Anderson, Linda Davis
Delaney, Margaret Lois
collection Datos científicos de ciencias marinas y ambientales
contents The Agulhas Ridge, off the tip of Africa between the Atlantic and Indian Oceans, is ideally located to capture the evolution of Paleogene-early Neogene circulation patterns associated with global cooling. Multiproxy records of productivity (biogenic barium (Baex), opal, CaCO3 mass accumulation rates (MARs)), nutrient and organic carbon burial (reactive phosphorus (Pr) MARs), and redox state of deep waters (U enrichment) from Ocean Drilling Program (ODP) Site 1090 reflect hydrographic shifts in this region between the middle Eocene and early Oligocene (~9–33 Ma). Several peaks in increased export productivity and burial of organic matter occurred within the late Eocene (~36.5, ~34, and ~33.7 Ma), which along with surface hydrologic conditions favoring opaline organisms over calcareous organisms could have aided in the draw down of pCO2 to a threshold level that facilitated large ice sheet development on Antarctica in the earliest Oligocene. Our multiproxy approach illustrates the importance of vertical as well as spatial hydrographic reorganization in amplifying or driving climatic cooling of the middle Eocene to early Oligocene by facilitating increases in the relative or absolute burial of organic carbon.
format Dataset Open Access
id pangaea_https___doi_org_10_1594_PANGAEA_837756
institution PANGAEA
language en
publishDate 2005
publisher PANGAEA
record_format pangaea
spellingShingle Geochemistry of Eocene/Oligocene sediments of ODP Site 177-1090
Anderson, Linda Davis
Delaney, Margaret Lois
177-1090B; 177-1090D; Accumulation rate, barium, excess; Accumulation rate, calcium carbonate; Accumulation rate, opal; Accumulation rate, phosphorus; AGE; Aluminium; Aluminium/Titanium ratio; Barium; Barium excess; Calcium; Calcium carbonate; Depth, composite; DEPTH, sediment/rock; DRILL; Drilling/drill rig; DSDP/ODP/IODP sample designation; Event label; Joides Resolution; Leg177; Manganese; Method comment; Ocean Drilling Program; ODP; Phosphorus, detrital; Phosphorus, reactive; Phosphorus, total; Sample code/label; Silicon dioxide; South Atlantic Ocean; Terrigenous; Titanium; Uranium
The Agulhas Ridge, off the tip of Africa between the Atlantic and Indian Oceans, is ideally located to capture the evolution of Paleogene-early Neogene circulation patterns associated with global cooling. Multiproxy records of productivity (biogenic barium (Baex), opal, CaCO3 mass accumulation rates (MARs)), nutrient and organic carbon burial (reactive phosphorus (Pr) MARs), and redox state of deep waters (U enrichment) from Ocean Drilling Program (ODP) Site 1090 reflect hydrographic shifts in this region between the middle Eocene and early Oligocene (~9–33 Ma). Several peaks in increased export productivity and burial of organic matter occurred within the late Eocene (~36.5, ~34, and ~33.7 Ma), which along with surface hydrologic conditions favoring opaline organisms over calcareous organisms could have aided in the draw down of pCO2 to a threshold level that facilitated large ice sheet development on Antarctica in the earliest Oligocene. Our multiproxy approach illustrates the importance of vertical as well as spatial hydrographic reorganization in amplifying or driving climatic cooling of the middle Eocene to early Oligocene by facilitating increases in the relative or absolute burial of organic carbon.
title Geochemistry of Eocene/Oligocene sediments of ODP Site 177-1090
topic 177-1090B; 177-1090D; Accumulation rate, barium, excess; Accumulation rate, calcium carbonate; Accumulation rate, opal; Accumulation rate, phosphorus; AGE; Aluminium; Aluminium/Titanium ratio; Barium; Barium excess; Calcium; Calcium carbonate; Depth, composite; DEPTH, sediment/rock; DRILL; Drilling/drill rig; DSDP/ODP/IODP sample designation; Event label; Joides Resolution; Leg177; Manganese; Method comment; Ocean Drilling Program; ODP; Phosphorus, detrital; Phosphorus, reactive; Phosphorus, total; Sample code/label; Silicon dioxide; South Atlantic Ocean; Terrigenous; Titanium; Uranium
url https://doi.org/10.1594/PANGAEA.837756