HAL : in2p3-00138066, version 1
 DOI : 10.1038/nature05266
 Nature 444 (2006) 82-84
 $^{10}$Be evidence for the Matuyama-Brunhes geomagnetic reversal in the EPICA Dome C ice core
 G.M. Raisbeck1, F. Yiou1, O. Cattani2, J. Jouzel2
 (2006)
 An ice core drilled at Dome C, Antarctica, is the oldest ice core so far retrieved 1. On the basis of ice flow modelling and a comparison between the deuterium signal in the ice with climate records from marine sediment cores, the ice at a depth of 3,190 m in the Dome C core is believed to have been deposited around 800,000 years ago 2, offering a rare opportunity to study climatic and environmental conditions over this time period. However, an independent determination of this age is important because the deuterium profile below a depth of 3,190 m depth does not show the expected correlation with the marine record 2. Here we present evidence for enhanced 10Be deposition in the ice at 3,160-3,170 m, which we interpret as a result of the low dipole field strength during the Matuyama-Brunhes geomagnetic reversal, which occurred about 780,000 years ago. If correct, this provides a crucial tie point between ice cores, marine cores and a radiometric timescale.
 Thème(s) : Physique/Physique/GéophysiquePlanète et Univers/Sciences de la Terre/GéophysiquePlanète et Univers/Sciences de la Terre/ClimatologiePlanète et Univers/Sciences de la Terre/Glaciologie
 in2p3-00138066, version 1 http://hal.in2p3.fr/in2p3-00138066 oai:hal.in2p3.fr:in2p3-00138066 Contributeur : Dominique Girod <> Soumis le : Vendredi 23 Mars 2007, 11:09:48 Dernière modification le : Vendredi 23 Mars 2007, 11:28:32