𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Late Quaternary sea-surface conditions at DSDP Hole 594 in the southwest Pacific Ocean based on dinoflagellate cyst assemblages

✍ Scribed by Fabienne Marret; Anne de Vernal; Ferial Benderra; Rex Harland


Publisher
John Wiley and Sons
Year
2001
Tongue
English
Weight
857 KB
Volume
16
Category
Article
ISSN
0267-8179

No coin nor oath required. For personal study only.

✦ Synopsis


Abstract

Investigation of organic‐walled dinoflagellate cyst distribution in 118 surface sediments from the Southern Ocean documents the relatively high diversity of cyst taxa (46 species) and distinct cyst assemblages in relation to surface water masses and temperature gradient. The Antarctic Water is characterised by the dominance of Selenopemphix antarctica accompanied by Brigantedinium spp. and Impagidinium pallidum. The Subantarctic Water association consists mainly of Nematosphaeropsis labyrinthus, Impagidinium paradoxum and Impagidinium sphaericum, whereas the Subtropical Water association is dominated by Operculodinium centrocarpum and Spiniferites membranaceus.

Multivariate analyses (non‐metric multidimensional scaling) demonstrate the relationships with sea‐surface conditions and enable the application of the best analogue method on the Southern Ocean dinoflagellate cyst data base for reconstructing past sea‐surface conditions. The dinoflagellate cyst record from DSDP 594 (45°31.41'S, 174°56.88'E; 1204 m, southern margin of the Chatham Rise) shows important fluctuations in species composition from glacial to interglacial over the last 140 000 yr. Reconstruction of winter and summer SSTs reveals much lower temperature than present by 6 to 10 °C during marine oxygen isotope stages 6, 4 and 2, and higher temperature by 2–3 °C during substage 5e. Copyright © 2001 John Wiley & Sons, Ltd.