Relative abundances of twenty-eight dominant benthic foraminifera species of DSDP Hole 23-219 (Table 1s)

Anil K Gupta; M Sundar Raj; Kuppusamy Mohan; Soma De

doi:10.1594/pangaea.706066

Relative abundances of twenty-eight dominant benthic foraminifera species of DSDP Hole 23-219 (Table 1s)

Citation

Gupta A K, Sundar Raj M, Mohan K, De S (2008). Relative abundances of twenty-eight dominant benthic foraminifera species of DSDP Hole 23-219 (Table 1s). PANGAEA - Publishing Network for Geoscientific and Environmental Data. Occurrence dataset https://doi.org/10.1594/pangaea.706066 accessed via GBIF.org on 2022-05-25.

Description

Tropical climate is variable on astronomical time scale, driving changes in surface and deep-sea fauna during the Pliocene-Pleistocene. To understand these changes in the tropical Indian Ocean over the past 2.36 Myr, we quantitatively analyzed deep-sea benthic foraminifera and selected planktic foraminifera from >125 µm size fraction from Deep Sea Drilling Project Site 219. The data from Site 219 was combined with published foraminiferal and isotope data from Site 214, eastern Indian Ocean to determine the nature of changes. Factor and cluster analyses of the 28 highest-ranked species distinguished four biofacies, characterizing distinct deep-sea environmental settings. These biofacies have been named after their most dominant species such as Stilostomella lepidula-Pleurostomella alternans (Sl-Pa), Nuttallides umbonifer-Globocassidulina subglobosa (Nu-Gs), Oridorsalis umbonatus-Gavelinopsis lobatulus (Ou-Gl) and Epistominella exigua-Uvigerina hispido-costata (Ee-Uh) biofacies. Biofacies Sl-Pa ranges from ~2.36 to 0.55 Myr, biofacies Nu-Gs ranges from ~1.9 to 0.65 Myr, biofacies Ou-Gl ranges from ~1 to 0.35 Myr and biofacies Ee-Uh ranges from 1.1 to 0.25 Myr. The proxy record indicates fluctuating tropical environmental conditions such as oxygenation, surface productivity and organic food supply. These changes appear to have been driven by changes in monsoonal wind intensity related to glacial-interglacial cycles. A shift at ~1.2-0.9 Myr is observed in both the faunal and isotope records at Site 219, indicating a major increase in monsoon-induced productivity. This coincides with increased amplitude of glacial cycles, which appear to have influenced low latitude monsoonal climate as well as deep-sea conditions in the tropical Indian Ocean.

Taxonomic Coverages

Chromista
rank: kingdom

Geographic Coverages

Event: 23-219, Indian Ocean/Arabian Sea/RIDGE ;

Bibliographic Citations

Contacts

Anil K Gupta
originator

M Sundar Raj
originator

Kuppusamy Mohan
originator

Soma De
originator

metadata author
PANGAEA - Data Publisher for Earth & Environmental Science
email: info@pangaea.de
homepage: https://www.pangaea.de

administrative point of contact
PANGAEA - Data Publisher for Earth & Environmental Science
email: info@pangaea.de
homepage: http://www.pangaea.de