29 juillet 2006

The Meuse river, recording recent tectonic evolution of the Variscan front

Auteurs: B. Van Vliet Lanoë, F. Lacquement, L. Voisin, J.L. Mansy, F. Meilliez

Année: 2006

Numéro revue: 1

Numéro article: 16

Abstract

The mapping of the deposits and terraces of the Meuse river were reanalysed in there geodynamical context. This work has been completed by the analysis of a DEM. The problem of the capture of the "Meuse ardennaise" and the "Meuse lorraine" by the Condroz Meuse is discussed. Two sets of deposits were observed between Charleville-Mézières and Givet, 1) an older one covering the Eocene to the Late Miocene characterized by a local origin of the sediments and 2) a younger one, reworking material from the Paris Basin and from the Vosges, covering the middle Pliocene to the Holocene. Below the "Middle terrace" deposits in several locations, we observed a late Miocene deposit. This means that the Ardenne Meuse was already deeply incised prior to Quaternary. The capture occurred at the level of the Maisoncel fault, with a drainage reversal. Terraces and deposits were correlated with dated elements. The Pliocene valley was filled up before being re-incised during the Quaternary. This clearly showed the impact on long wavelength deformations on the terrace incision, though deposits occurred mostly during relaxation events. These successive deformations led to a pulsated moderate uplift of the Western Ardenne by reactivation of the Variscan structures.

Key words: Tertiary, Quaternary, Terraces, Uplift, Neotectonics, Belgium, Ardennes France, Meuse Valley