Successive post-Variscan stress fields in the French Massif Central and its borders (Western European plate): comparison with geodynamic data

Gravity inversion, AMS and geochronological investigations of syntectonic granitic plutons in the southern part of the Variscan French Massif Central

“…However, this hypothesis must be carefully considered since it does not distinguish the different kinematics between the late and post extensional phases. Indeed, when dealing with the post-orogenic event, this interpretation is in agreement with available data (Bonijoly and Castaing 1987;Blès et al 1989;Burg et al 1990;Faure 1995) since it may account for the development of transtensional pull-apart coal basins. However, when dealing with the syn-orogenic event, the N-S trend of the SHF is not in agreement with the NW-SE ductile stretching that developed at that time, as observed in most parts of the FMC (Faure, 1995).…”

“…Its Late Carboniferous (Stephanian) left-lateral brittle motion is well documented (Letourneur 1953;Grolier and Letourneur 1968;Bonijoly and Castaing 1987;Blès et al 1989). It has been argued that the SHF was a transfer fault that accommodated the extensional tectonics of the FMC (Burg et al 1990).…”

Meso-Cenozoic geodynamic evolution of the Paris Basin: 3D stratigraphic constraints

“…In the Paris Basin, N-S extension is assumed for the Permian and the Triassic [189,190] based on few microtectonic data in the Massif Central [191] and on the E-W orientation of the Lower Keuper salt depocentre. Along the Ardeche palaeomargin [192] a structural study of orientated cores suggest an E-W extension in the Ladinian (late Middle Triassic)-early Carnian (early Upper Triassic) with tilting (before the deposition of the Barre carbonatee rnediane, a time-equivalent of the Lettenkohle).…”

New Early Permian paleomagnetic results from the Brive basin (French Massif Central) and their implications for Late Variscan tectonics

“…The study of AMS has been carried out to make a knowledge on depositing horizontal and to detect possible posterior deformation (Blès et al 1989). Magnetic foliation poles (minimum susceptibility axes K 3 ) generally show steep inclinations ( Fig.…”

“…For this fault, a Late Carboniferous left-lateral displacement of about 50 km is documented on the basis of offset of geological features (plutons, faults, metamorphic series, etc., e.g., Grolier and Letourneur 1968;Blès et al 1989).…”