Late Quaternary palaeoceanography of the Circumpolar Deep Water from the South Tasman Rise

• Published in: Journal of Quaternary Science
• Main Authors: Moy, Andrew D., Howard, William R., Gagan, Michael K.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2006
• Subjects: Paleontology; Earth and Planetary Sciences (miscellaneous); Arts and Humanities (miscellaneous); Southern Ocean; Pacific; Indian; South Tasman Rise
• Online Access: http://dx.doi.org/10.1002/jqs.1067; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fjqs.1067; https://onlinelibrary.wiley.com/doi/pdf/10.1002/jqs.1067

Abstract We use sediment cores from the South Tasman Rise (STR) to reconstruct deep‐ water circulation in the southwest Pacific sector of the Southern Ocean. Sediment cores MD972106 (45° 09′ S, 146° 17′ E, 3310 m water depth) and GC34 (45° 06′ S, 147° 45′ E, 4002 m water depth) preserve records covering the last 160 k yr, with chronology controlled by calibrated accelerator mass spectrometry radiocarbon dates and benthic foraminiferal δ 18 O tied to SPECMAP. The STR benthic foraminiferal δ 13 C records provide new δ 13 C values for Southern Ocean deep water spanning the last 160 k yr at sites unlikely to be affected by variations in productivity. The records establish that glacial benthic foraminifera ( Cibicidoides spp.) δ 13 C values are lower relative to interglacial values and are comparable to previous glacial benthic δ 13 C records in the Indian and Pacific sectors of the Southern Ocean. Comparisons of the benthic foraminiferal δ 13 C time series at the STR are made with the equatorial Pacific (V19‐30 and Site 846) and the equatorial Atlantic (GeoB1115). The similarity of benthic δ 13 C records at the STR to the equatorial Pacific suggest the Southern Ocean deep‐water mass closely tracked those of the deep Pacific, and the presence of a δ 13 C gradient between the STR and the equatorial Atlantic suggests there was continual production of northern source deep water over the past 160 k yr. Copyright © 2006 John Wiley & Sons, Ltd.