The Meuse section across the Condroz–Ardennes (Belgium) based on a predeformational sediment wedge

A compressional wedge model for the Lower Palaeozoic Anglo-Brabant Belt (Belgium) based on potential field data

“…(1) the metamorphic contour line, separating the diagenetic zone in the SW of the Brabant Massif, probably coincides with the Caledonian deformation front (Woodcock 1991); to the SW of this deformation front no Caledonian deformation has been observed in the Lower Palaeozoic strata (Verniers & Van Groote11991;Van Grootel et al 1997); the presence of persistent shelf sediments in the Silurian is also considered indicative of the presence of a cratonic basement (Verniers et al 2002); (2) as in the Welsh Basin (Soper et al 1987) the arcuate structural grain of the deformed southern Ordovician-Silurian foreland basin may be considered to be parallel to the deformation front, situated to the south underneath the Variscan Ardenne Allochthon; Sintubin (1999) has defined the (1) the central 'steep belt' of the Brabant Massif formed a compressional wedge, situated in between two crustal basement blocks: the Midlands-Ardennes Microcraton to the SW and the Ltineburg-North Sea Microcraton to the NE; the entire sedimentary, Lower Palaeozoic, cover sequence has been detached from its basement, resulting in significant tectonic thickening; (2) the basal Variscan d6collement, currently considered to be situated within the Lower Palaeozoic rocks (Adams & Vandenberghe 1999;Oncken et al 1999Oncken et al , 2000 may be situated at the interface between a Lower Palaeozoic cover sequence and a Precambrian crystalline basement; disposition may have some important tectonic implications with respect to the ongoing discussion whether or not these Ardennes Inliers have suffered an Ordovician deformation event (e.g. Hugon & Le Corre 1979;Delvaux de Fenffe & Laduron 1984Le Gall 1992;Hugon 1983;Piessens & Sintubin 1997;Belanger 1998;Verniers et al 2002): (a) if the Ardenne Inliers originated from the Lower Palaeozoic cover sequence of the cratonic basement, these Lower Palaeozoic rocks did not suffer any Ordovician deformation; this is very similar to the Cambrian-Ordovician, diagenetic to lower anchizonal, sediments on top of the Midlands Microcraton that lack a tectonic fabric (Lee et al 1990); this would imply that all deformation, observed in the Ardenne Inliers, is Variscan (Hugon & Le Corre 1979;Hugon 1983;Le Gall 1992).…”

The Stavelot-Venn Massif (Ardenne, Belgium), a rift shoulder basin ripped off the West African craton: Cartography, stratigraphy, sedimentology, new U-Pb on zircon ages, geochemistry and Nd isotopes evidence

“…The SVM is the northernmost Variscan thrust nappe of the Rheno-Hercynian foreland fold-and-thrust belt (Franke, 2000;Oncken et al, 1999Oncken et al, , 2000. It was transported at least 20 to 30 km to the northwest towards the Brabant Massif (Adams and Vandenberghe, 1999;Hance et al, 1999;Oncken et al, 2000). As a consequence, it has undergone Variscan folding and very low (anchizone) to low-grade (epizone) metamorphism during Upper Carboniferous times (e.g.…”

“…The distance between the SVM and the Midi-Aachen Fault is currently of c. 40 km. Before the Caledonian and Variscan folding and thrusting, this distance can be estimated at a minimum of 100 km taking into account a regional shortening of c. 50% (Adams and Vandenberghe, 1999;Oncken et al, 2000;Nierhoff et al, 2011). This implies that the Brabant-Condroz and the SVM basins have been close during their development.…”

Evolution of Mullion (Boudin) structuresin the Variscan of the Ardennes and Eifel

“…3). The important differences in sediment thickness and the involvement of basement massifs in the thrust sequence are the main factors influencing the typical outcrop pattern of the region (Adams & Vandenberghe, 1999;Fielitz, 1992;Hollman & von Winterfeld, 1992;Hollmann & Walter, 1995;Hance et al, 1999).…”