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The Taurus Mountains are an E-W trending mountain range in southern Turkey, with an elevation of up to 3500 m. In the south central Taurides, the Beysehir-Hoyran-Hadim nappes, a series of thrust sheets of Palaeozoic to Early Cenozoic age, are emplaced onto a relatively autochthonous Tauride platform, known as the Geyik Dag. These thrust sheets consist of a variety of discrete tectonostratigraphic units of continental platform, rifted margin and oceanic (ophiolitic) origin. It is generally accepted that the relatively autochthonous Tauride platform and the associated thrust sheets restore as a north-facing passive margin during Jurassic–Cretaceous time; however, the Triassic and earlier tectonic setting of the Tauride units is contentious. New data (mainly structural and sedimentological) presented here tests contrasting tectonic models of Late Palaeozoic – Early Mesozoic Tethys ocean evolution. Also, new light is shed on the Late Cretaceous and Early Cenozoic break-up and emplacement of the Tauride units during closure of Tethys. The Late Palaeozoic Tauride stratigraphy consists of shallow-marine carbonate, sandstone and mudstone, characteristic of a proximal passive margin. Detailed stratigraphic logging, facies interpretation, compositional analysis and geochemical evidence supports a passive margin setting, with sediment derived from the Tauride “basement”. Early – Middle Triassic mixed siliciclastic/carbonate sediments are interpreted as representing rifting and subsidence. Late Triassic coarser terrestrial clastics (Cayir Formation) are considered to represent a pulse of rift-related flexural uplift. Sediment provenance during this time was from the underlying Tauride platform to the north of the studied area. A previous hypothesis that a Palaeotethyan ocean closed in this area during latest Triassic “Cimmerian” orogenesis is discounted. Instead, structural and sedimentary data suggest that all of the deformation relates to Late Cretaceous – Early Cenozoic southward emplacement of the Beysehir-Hoyran-Hadim nappes. A first phase of thrusting (thin-skinned) emplaced ophiolite and distal margin units, whilst a second phase (thick-skinned) thrust platform lithologies southwards onto the foreland. Evidence is also summarised, notably from the Palaeozoic – Early Mesozoic Konya Complex to the north, which illustrates the relation of the Tauride platform to other geological terranes in Turkey and elsewhere in the Alpine-Himalayan orogenic belt. This thesis increases understanding of large-scale tectonic and sedimentary processes associated with continental margins and orogenic development.

L’ouverture de l’Océan Néotéthys au nord du bassin de Ghadamès et de la Jeffara s’accompagne d’une phase d’extension. Ceci engendre une phase de subsidence qui se traduit par le dépôt des premières séries syn-rift d’âges Permien moyen à supérieur (formation El Watiah) et Trias inférieur à moyen (formations Bir el Jaja, Ouled Chebbi et Ras Hamia/Kirchaou). Cette étude propose la compréhension de l’architecture stratigraphique et séquentielle des formations triasiques détritiques, et de la partie supérieure clastique de la formation El Watiah. 221 puits et 18 coupes sédimentologiques de terrain (affleurements du Sud tunisien) ont été corrélées à travers l’ensemble du bassin de Ghadamès et de la Jeffara. Il est démontré que ces séries s’organisent en 11 séquences de 3ème ordre. 28 cartes d’isochores et de paléogéographie ont été réalisées. D’un point de vue tectonostratigraphique, un épaississement drastique des séquences a notamment été confirmé en direction du nord de la Jeffara, à la faveur d’une subsidence forte et très différentielle. Dans le sud du bassin, un domaine caractérisé par une subsidence faible et peu différentielle a aussi été reconnu. Par ailleurs, une réinterprétation sédimentologique de la formation du TAGI de la région d’El Borma (équivalent latéral de la formation ladinienne Ras Hamia) a été proposée. / During the opening of the Neotethys Ocean north of the Ghadames and Jeffara basin, an extensional phase created subsidence. It resulted in the deposition of the first syn-rift strata aged Middle to Upper Permian (El Watiah formation) and Lower to Middle Triassic (Bir el Jaja, Ouled Chebbi and Ras Hamia / Kirchaou formations). This study provides details of the stratigraphic and sequential architecture of triassic siliciclastic series and the upper clastic part of the El Watiah formation. 221 wells and 18 sedimentological field sections (outcrops from south Tunisia) have been correlated across the entire Ghadames basin and Jeffara. An organization in 11 sequences has been highlighted. 28 isochores and paleogeographic maps have been drawn. In terms of tectonostratigraphy, a major thickening of sequences has been confirmed toward the North of Jeffara, resulting from a very strong and differential subsidence. Low and subtle differential subsidence has been demonstrated in the southern part of the basin. In addition, a new sedimentological interpretation of the TAGI formation (lateral equivalent of the ladinian Ras Hamia formation) has been considered in the El Borma area.