Highly deformed basal ice in the Vostok core, Antarctica

R. Souchez (1) , J.R. Petit (2) , J. Jouzel (3, 4) , J. Simões (2) , M. de Angelis (2) , N. Barkov (5) , M. Stievenard (3, 4, 6) , F. Vimeux (3, 4) , J. Sleewaegen (1) , R. Lorrain (1)

1 ULB - Université libre de Bruxelles
2 LGGE - Laboratoire de glaciologie et géophysique de l'environnement
3 LSCE - Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette]
4 GLACCIOS - Glaces et Continents, Climats et Isotopes Stables
5 AARI - Arctic and Antarctic Research Institute
6 GEOTRAC - Géochrononologie Traceurs Archéométrie

Our paper documents the build‐up of a highly deformed basal ice layer in the basal part of the Vostok ice core. This is done mainly on the basis of an isotopic composition investigation of the ice. Complex deformation in the lower 228 m of the ice sheet has resulted in folding and intermixing of ice at a submetric scale and, for the upper part of this basal sequence, in interbedding of ice layers from distinct origins at a larger scale. This complex deformation occurred at a temperature largely below the pressure‐melting point. The basal ice layer has built upwards and size‐selective incorporation of bed material into the ice has taken place. The documentation of this complex basal deformation has implications for the maximum age of ice that will be useful in paleoclimate studies and for ice sheet dynamics.

Mots clés: 1040 Geochemistry: Isotopic composition/chemistry; 1827 Hydrology: Glaciology (1863); 4540 Oceanography: Physical: Ice mechanics and air/sea/ice exchange processes; 9310 Information Related to Geographic Region: Antarctica

Domaines: Océan, Atmosphère; Interfaces continentales, environnement

R. Souchez, J.R. Petit, J. Jouzel, J. Simões, M. de Angelis, et al.. Highly deformed basal ice in the Vostok core, Antarctica. Geophysical Research Letters, 2002, 29 (7), ⟨10.1029/2001GL014192⟩. ⟨hal-03106876⟩