Structure de la Zone Houillere Brianconnaise (Alpes francaises), tectonique neoalpine et consequences sur l'interpretation des Zones Penniques Frontales

Beneath the "Zone Houillere Brianconnaise' (ZHB), the ECORS seismic profile shows a singular cross pattern. From new structural data from the "Vallee des Belleville', a new kinematic model is proposed which brings into question the classical interpretation of these reflectors. The problem is: are they related to the "Brianconnais' (BF) and Pennine Fronts (PF) or not. It appears that the so-called BF and PF, classically interpreted as corresponding to the two east-dipping bands of reflectors, are more likely related to a Neoalpine extensional event than to earlier tectonic contacts, original BF and PF, which separate palaeogeographic domains. There is an abridged English version. -English summary