3.1 Introduction
Frédéric BOULVAIN, Isabelle BELANGER, Dominique DELSATE, Pierre GHYSEL, Pascal GODEFROIT, Martin LALOUX, Roger MONTEYNE & Marc ROCHE.
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ABSTRACT. A multidisciplinary study of some extensively cored boreholes together with the new 1/25,000 geological mapping of Wallonia led us to propose a new lithostratigraphic canvas for Belgian Lorraine. This area is located on the NE border of the Paris Basin, south of the Ardennes; the studied stratigraphic interval covers the Late Triassic to the Bajocian.
KEYWORDS. Mesozoic, stratigraphy, Belgium, Lorraine, Triassic, Jurassic, Paris Basin.
The Mesozoic formations of Belgian Lorraine, outcropping on approximately 800 km2 (fig. 1), are a north-eastern dependence of the Paris Basin, forming the so-called Gulf of Luxemburg. The nature and the complex geometry of sedimentary bodies indicate a littoral environment characterized by a mixed sedimentation with a siliciclastic predominance. The sequential evolution of deposits was integrated in a globally retrograding sedimentary prism.
Figure 1. Simplified geological map of Belgian Lorraine.
Except for some famous sections, mainly located in the sandy Sinemurian, boreholes constitute the principal geological data source for Belgian Lorraine. Detailed lithological descriptions are provided in the following publications:
- Arlon borehole 219E254: Gulinck et al. (1973);
- Latour borehole 225E189: Boulvain and Monteyne (1993), Boulvain et al. (1995);
- Neulimont borehole 222W253, Saint-Mard borehole 225W145, Toernich borehole 219E614, Aubange borehole 223E493: Boulvain et al. (1995);
- Villers-devant-Orval borehole 221E87: Boulvain et al. (1996).
Since Dumont's (1842) precursory report and the synthesis by Maubeuge (1954), studies in Belgian Lorraine have been almost exclusively devoted to lithostratigraphy and biostratigraphy. Recent works concern sedimentological studies of the Sinemurian sandy body and the Aalenian "Minette" (i.e. Berners, 1983; Teyssen, 1984; Mergen, 1984; Muller & Steingrobe, 1988; Guerin-Franiatte et al., 1991). Boulvain et al. (2001) propose a progress report on lithostratigraphy, sedimentology, mineralogy and palaeontology of Belgian Lorraine.
This paper successively deals with the Habay, Attert, Mortinsart, Jamoigne, Luxembourg, Arlon, Ethe, Messancy, Aubange, Grandcourt, Mont-Saint-Martin and Longwy Formations (fig. 2).
Figure 2. E-W schematic lithostratigraphic section of Belgian Lorraine.