Henri Rouvier

Le Trias a caractere extrusif de la zone des domes; example de la structure de Debadib-Ben Gasseur (Tunisie septentrionale)

The Debadib-Ben Gasseur anticlinal structure, situated between El Kef and the Algero-Tunisian border, belongs to one of the main diapiric, alignments of the oriental Maghreb. It constitutes an elliptic form oriented NE-SW. The heart is occupied by Triassic residual evaporites containing basaltic volcanites which seem to indicate an extensional setting during the Triassic period. The contact between the saliferous bodies and surrounding Cretaceous-Tertiary age rocks is locally underlined by conglomerates including reworked Triassic blocks and glauconite, suggesting a sedimentary contact. Biostratigraphic and sub-surface data could indicate, in terms of model reconstitution, an extrusive system with numerous phases starting in the Aptian and acting until the Tertiary period. However, tectonic events are clearly expressed during the Miocene.