A 220 kyr record of Pb isotopes at Dome C Antarctica from analyses of the EPICA ice core

Vallelonga, P. and Gabrielli, P. and Rosman, K. J. R. and Barbante, C. and Boutron, C. F. 2005. A 220 kyr record of Pb isotopes at Dome C Antarctica from analyses of the EPICA ice core. Geophysical Research Letters. 32 (1).

Source Title

Geophysical Research Letters

DOI

10.1029/2004GL021449

ISSN

00948276

Faculty

Department of Medical Imaging and Applied Physics

School of Science

Faculty of Science and Engineering

School

Department of Imaging and Applied Physics

Remarks

URI

http://hdl.handle.net/20.500.11937/22539

Collection

Curtin Research Publications

Abstract

[1] Pb isotopic compositions and Pb and Ba concentrations are reported in EPICA Dome C ice core samples dating to 220 kyr BP, indicating that Pb isotopic compositions in Antarctic ice vary with changing climate. 206Pb/207Pb ratios decrease during glacial periods, with the lowest values occurring during colder climatic periods (stages 2, 4 and 6) and the Holocene. Low Pb concentrations (<1 pg/g) were found during the Holocene and the last interglacial (climate stage 5.5) while higher Pb concentrations (>10 pg/g) were found during cold climatic periods. Ba, a proxy for mineral dust, was used to determine that dust usually accounts for ~ 70% of Pb in Dome C ice, while the remaining ~ 30% was attributed to volcanic emissions. Pb isotopic compositions at Dome C differ from those reported in pre-industrial ice from other Antarctic locations, due to greater proportions of dust Pb at Dome C.