nerc.ac.uk

Molluscan stable isotope temperature estimates of the southwestern Ross Sea during the Early Oligocene and Early Miocene, CRP-2/2A and CRP-3, Victoria Land basin, Antarctica

Lavelle, M.; Fielding, C.R.; Hall, M.A.; Thomson, M.R.A.. 2001 Molluscan stable isotope temperature estimates of the southwestern Ross Sea during the Early Oligocene and Early Miocene, CRP-2/2A and CRP-3, Victoria Land basin, Antarctica. Terra Antartica, 8 (4). 439-444.

Full text not available from this repository. (Request a copy)

Abstract/Summary

Stable isotope analyses of marine bivalve growth increment samples have been used to estimate early Oligocene (29.4 - 31.2) Ma and early Miocene (24.0 Ma) seafloor palaeotemperatures from the southwestern continental margin of the Ross Sea. Measured d18O values average +2.5‰ in the early Miocene and range between +1.26 to +3.24‰ in the early Oligocene. The results show that palaeoceanographic conditions in McMurdo Sound during the mid-Cenozoic were significantly different from those of today. The minimum estimated spring through late summer seasonal temperature range was 3°C during the early Miocene and between 1 and 5°C during the early Oligocene. This compares to the equivalent modern day range of <0.5°C within the sound. Absolute seawater temperatures at <100 m depth were of the order of 5 to 7°C during both time slices, compared to modern day values of -1.4 to -1.9°C in the same area. The results are in broad agreement with early Oligocene Mg/Ca temperature estimates from deep Atlantic foraminifera as well as estimates from local terrestrial palynology and palaeobotany.

Item Type: Publication - Article
Programmes: BAS Programmes > Other
Date made live: 02 Oct 2012 07:58
URI: http://nora.nerc.ac.uk/id/eprint/19811

Actions (login required)

View Item View Item