Trias du Jura
Trias moyen
Deutsch: Zeglingen-Formation (Anhydritgruppe)
Français: Formation de Zeglingen
Italiano: Formazione di Zeglingen
English: Zeglingen Formation
Heterogene, zyklische evaporitische Abfolge (ehem. «Anhydritgruppe») im mittleren Teil der Muschelkalk-Gruppe der Nordschweiz: Steinsalz, massive und mergelige Anhydrite, Dolomite.
Zeglingen (BL)
«Mittlerer Muschelkalk» auct., «Anhydritgruppe» auct., Zeglingen-Formation (Jordan 2016)
The Zeglingen Formation includes the Anisian evaporitic sequence and corresponds to the «Anhydritgruppe» («Mittlerer Muschelkalk») of the traditional Swiss scheme (e.g. Mu¨ller et al. 1984, see also Fig. 3. The only discrepancy concerns the «Unterer Dolomit» which is now part of the underlying Kaiseraugst Formation and was formerly considered as part of the «Anhydritgruppe» by some authors (c.f. Matter et al. 1988). One reason is that the German stratigraphic scheme incorporates the «Unterer Dolomit» into the Karlstadt Formation (former «Orbicularismergel»), which corresponds to the upper part of the Kaiseraugst Formation. On the other hand, a close examination shows that in most core reports, the boundary between «Wellengebirge» and «Anhydritgruppe» was set at the base of the first massive anhydrite sequence. The newly defined boundary also corresponds to the morphologic change from carbonate-dominated rocks (below), which resist erosion, to more soluble sulphates (above).