Prospecting for Last Interglacial speleothems in Vercors
Résumé
The Last Interglacial (LIG, ~130116 ka) was one of the warmest interglacials of the past 800,000 years. Speleothems offer superior age control and a few LIG records are available from the Eastern Alps. In order to prospect for LIG speleothems in the Western Alps, we drilled small diameter cores at the base of stalagmites. In the Vercors, we sampled 27 speleothems in 6 different caves and dated them using the U Th method. Here, we present the results of these reconnaissance drilling campaigns. Although, to our surprise, we did not identify stalagmites of LIG age, the resulting ages provide useful chronological information on the individual karst settings. Among these 27 ages, 5 are Holocene, the others belong to Marine Isotope Stage 2 (5 samples), 3 (2), 5a (1) and 5c (1), 8 (1), 9 (2), 11 (4), 12 (1), 13 (1) and 4 are beyond the U Th dating limit. These dates can help to re assess the age of certain cave conduits and the evolution of this well documented karst region. In addition, they may serve as a basis for future speleothem based paleoclimate studies of the Vercors.
Domaines
Sciences de l'environnementOrigine | Fichiers produits par l'(les) auteur(s) |
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