(Table 1) Comparison of diatom-bound and bulk sedimentary d15N values of ODP Holes 175-1082A and 175-1084A ...

• Main Authors: Robinson, Rebecca S, Meyers, Philip A
• Format: Dataset
• Language: English
• Published: PANGAEA 2002
• Subjects: Event label; Sample code/label; DEPTH, sediment/rock; AGE; δ15N, bulk sediment; δ15N, diatom-bound organic matter; Δδ15N; Drilling/drill rig; DSDP/ODP/IODP sample designation; Leg175; Joides Resolution; Ocean Drilling Program ODP; Antarc*; Antarctic; Southern Ocean
• Online Access: https://dx.doi.org/10.1594/pangaea.842475; https://doi.pangaea.de/10.1594/PANGAEA.842475

The Matuyama Diatom Maximum (MDM) is a time of peak opal accumulation from 2.6 to ~2.0 Ma within the Benguela Current upwelling system that was initiated by increased influence of Southern Ocean water on the eastern South Atlantic. We measured opal, total organic carbon (TOC), and CaCO3 fluxes and C and N stable isotopes in sediments deposited from 2.4 to 1.95 Ma at Sites 1082 and 1084 to explore the biogeochemical dynamics within the Benguela region. The infusion of Southern Ocean water delivered dissolved nutrients and Southern Ocean flora and fauna, resulting in local opal accumulation increasing up to 8 g/cm**2/ky and the production of diatom mats. Some d15N measurements of diatom-bound organic matter indicate that the mats grew within the Benguela region. The bulk sediment d15N records are taken to reflect changes in the d15N of nitrate in the incoming water, where lower values at 2.4 Ma reflect less nitrate utilization in the Antarctic. A long-term increase in relative nitrate uptake in the Southern ... : Supplement to: Robinson, Rebecca S; Meyers, Philip A (2002): Biogeochemical changes within the Benguela Current upwelling system during the Matuyama Diatom Maximum: Nitrogen isotope evidence from Ocean Drilling Program Sites 1082 and 1084. Paleoceanography, 17(4), 1064 ...