TCD The Cryosphere Discussions TCD 1994-0440 Copernicus GmbH Göttingen, Germany 10.5194/tcd-7-321-2013 Radar stratigraphy connecting Lake Vostok and Dome C, East Antarctica, constrains the EPICA/DMC ice core time scale Cavitte M. G. P. 1 Blankenship D. D. 1 Young D. A. 1 Siegert M. J. 2 Le Meur E. 3 Institute of Geophysics, University of Texas at Austin, TX 78758, USA Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, Bristol BS8 1SS, UK Laboratoire de Glaciologie et Géophysique de l'Environnement, CNRS, UJF-Grenoble I, BP 96, 38402 Saint-Martin d'Hères, France 22 01 2013 7 1 321 342 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.the-cryosphere-discuss.net/7/321/2013/tcd-7-321-2013.html The full text article is available as a PDF file from http://www.the-cryosphere-discuss.net/7/321/2013/tcd-7-321-2013.pdf

New airborne radar sounding surveys at 60 MHz are used to trace internal layering between the Vostok and EPICA Dome C ice core sites. Eleven layers, spanning two glacial cycles from the last glacial maximum back to the MIS 7c interglacial, are used to correlate the two ice core chronologies. Independent of palaeoclimate signals, radar sounding enables correlation of the timescales, with a radar depth uncertainty equivalent to hundreds of years, which is small relative to the ice core dating uncertainties of thousands of years. Along the radar transects, horizons belonging to the last glacial cycle are impacted by aeolian stratigraphic reworking that increases radar technique uncertainty for this interval. However, older layers are used to propagate the higher resolution Vostok ages to the lower resolution Dome C ice core using the Suwa and Bender (2008) Vostok O<sub>2</sub> / N<sub>2</sub> chronology to give a recalibration of the Parrenin et al. (2007) EPICA EDC3 timescale between 1597 m and 2216 m depth (126 ka to 247 ka age interval).

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