Les ammonites les plus récentes du Luxembourg et de la région frontalière franco-luxembourgeoise : Sonniniidés, Stephanoceratidés et Sphaeroceratidés du Bajocien (Jurassique moyen).

Abstract

The youngest Mesozoic sediments in Luxembourg are those of the Bajocian in the southwestern part of Luxembourg along the French border. The “Marnes sableuses d’Audun-le-Tiche” and the “Calcaire de Nondkeil“ units had previously been dated from the Lower Bajocian Humphriesianum ammonite zone, based on sporadic ammonite findings reported in the literature. Re-studying material from the collection of the Luxembourg National Museum for Natural History allowed identifying 17 ammonite species from the families Sonninidae, Stephanoceratidae and Sphaeroceratida. The herein described ammonites provide evidence that all three subzones of the Humphriesanum Zone, namely the Romani, Humphriesianum and Blagdeni subzones, are present in the Rumelange area. The stratigraphically youngest ammonite from the Grand-Duchy is represented by one specimen of Teloceras from the plateau south of Differdange.