Nouvelles donnees sur le tephra de Sarlieve et le tephra CF7, marqueurs chrono-stratigraphiques de Grande Limagne (Massif central, France)

摘要

A trachytic tephra, discovered in the ancient lake of Sarlieve, 'Grande Limagne', has been dated using the thermoluminescence technique. The obtained age, 16 +- 4 ka (2σ), is older than that of the trachytic volcanoes of the Chaine des Puys, the ashes of which have already been locally recognised in the region. Its analysis confirms its originality. In the course of the comparisons made to search for its spring, it appears that the wide-dispersion tephra CF7, beforehand correlated by hypothesis to the Puy de Clierzou, probably originates from the Kilian crater or the Puy de Vasset.