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The stratigraphic evolution, structural styles, and principal hydrocarbon prospects of the Tunisia-Sicily shelf are all linked to the crustal "template" created during the middle Mesozoic rifting of the Tethyan margin of North Africa. Transtensional stretching and fragmentation of the Tunisia-Sicily shelf during the Late Triassic to Jurassic at the junction of the south Sahara and Gilbraltar fracture zones created a complex array of ridges and furrows and localized pull-apart basins. This block-faulted shelf region was buried during the Cretaceous and early Cenozoic beneath a cover stratigraphy that ranged widely from a thin pelagic limestone succession devoid of terrigenous components in Sicily to a considerably thicker neritic Tunisian succession containing terrigenous nd carbonate rocks. Differences in stratigraphic character across the shelf relate to the relative position of Sicily and Tunisia between the unstable and subsident Tethyan margin and the stable and emergent Saharan platform. As the North African continental margin subducted northward beneath the accretionary Kabyle-Calabrian belt in the late Cenozoic, the thin carbonate successions of Sicily responded by detaching in a series of southward-migrating thrust sheets. Along strike in Tunisia, the thrust sheets die out and stress was taken up by folding the thick marly succession weakened by numerous Late Triassic evaporite diapirs. Despite differences in structural style, the orientations of the structures in both Tunisia and Sicily have been guided by the crustal template created by middle esozoic rifting.
Hydrocarbons on the Tunisian-Sicily shelf are related to (1) Mesozoic or younger structures that deform the early Paleozoic black shale-orthoquartzite succession of the Saharan platform, (2) synrift anoxic basin facies, (3) the Cretaceous-early Cenozoic shelf margin in the Tunisian section, and (4) late Cenozoic synorogenic clastic facies.
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