L'affleurement triasique du Debadib–Ben Gasseur (Nord-Ouest de la Tunisie) : diapir enraciné à épanchements latéraux dans la mer Albienne, replissé au cours des phases de compression tertiaires

Abstract

The Triassic rocks of the Debadib-Ben Gasseur area (northwestern Tunisia): diapir with overhangs spreading downslope in the Albian Sea and deformed during the Tertiary compressional deformations. The Triassic outcrops of the Debadib-Ben Gasseur area, located in the Kef area (northwestern Tunisia) have recently been interpreted as submarine 'salt glaciers' interbedded within the Albian deposits (J.-M. Vila et al., C. R. Acad. Sci. Paris, Ser. II 318 (1994) 1661-1667). New cartographic, drills and gravimetric data recognised evidence for an Albian diapiric stage for the Triassic rocks. The Triassic rocks as pulling out of the sedimentary cover could spread laterally as small size 'salt glaciers' before they have been deformed during the Tertiary compressional deformations. To cite this article: M.

Neogene-Quaternary structuring of the Kalaa Khesba Graben, northwestern Tunisia: A push-up inversion structure

“…Slata one may observe a centrifugal inversion of the host series during the emplacement of the Triassic material (Perthuisot et al, 1998). The Triassic outcrops of the diapirs zones show a certain complexity in the relationships between saliferous material and its host rock (Chikhaoui et al, 2002). The study area is characterized by major NW-SE and NE-SW faults.…”

“…In fact, the Upper Cretaceous-Lower Tertiary extension, followed by the Mio-Plio-Quaternary compression are affected by this Eo-Cretaceous structuration (Martinez et al, 1991). The developed faulting systems play a major role in the migration of saliferous material (Smati, 1983;Perthuisot and Rovier, 1988;Martinez et al, 1991;Chikhaoui, 1998;Chikhaoui et al, 2002;Ghanmi, 2003;Ben Chelbi et al, 2006;Ezzine, 2011). The triggering of the halokinetic movements which occurred during the Upper Cretaceous in various parts of northern Tunisia seems to be due to the major faulting network affecting the Tunisian basement (Perthuisot et al, 1988).…”

The Albian oceanic anoxic events record in central and northern Tunisia: Geochemical data and paleotectonic controls

“…1). Northwest-Southeast and Northeast-Southwest trending faults controlled the position and initiation of the sedimentary basins that were cut by North-South and East-West trending transverse faults (Sainfeld 1951;Burollet, 1956;Burollet and Sainfeld, 1956;Chikhaoui, 1988;Chikhaoui et al, 2002). The reactivation of the main faults associated with these structural trends and the Triassic diapirism has resulted in a complex tectonic history.…”

“…Consequently, the structural evolution of this region has been controlled by successive extensional and compressive tectonic events that also involved halokinesis (Perthuisot 1978;Ben Ayed 1986Boukadi 1996;Perthuisot et al, 1998;Kadri and Ben Haj Ali, 1999;Chikhaoui et al, 2002).…”

“…This region is located at the South-Western extremity of the diapir zone (Perthuisot, 1978;Hatira et al, 2000). It is represented by complex tectonic structures related to the Triassic evaporitic deposits ascension movements and strike-slip faults (Chikhaoui et al, 1991(Chikhaoui et al, , 2002Chikhaoui and Turki, 1996;Memmi, 1999) (Fig 1). According to these authors, the structural style complexity was the result of the extensive tectonic movement, which led to the extrusion of Triassic evaporites during the Aptian-Albian period.…”