ABSTRACT: Basins and Thrust Belts in Western Turkey: Tectonic History and Hydrocarbon Potential

P. R. Bird, C. C. Johns, D. D. Clark-Lowes

Western Turkey consists of a number of tectonic terranes joined together by a network of suture zones. The terranes originated as microcontinental plates that rifted away from the continental margins forming the northern and southern boundaries of the Tethyan sea. These micro-continents were united by a series of collisions beginning in the Late Triassic and ending in the Miocene, with the final closure of the Tethyan sea.

The sedimentary cover of the microcontinents consists of Palaeozoic and Mesozoic passive margin and rift basin sequences containing numerous potential source and reservoir intervals. Most of these sequences show affinities with Gondwanaland, with the notable exception of the Instanbul nappe, which is strongly Laurasian in character. Forearc basin sequences were also deposited on the margins of the microcontinents during early Tertiary plate convergence.

Ensuing continental collisions resulted in compressional deformation of sedimentary cover sequences. The intensity of deformation ranged from basin inversion, producing numerous potential hydrocarbon traps, to large-scale overthrusting. Following continental suturing, continued compression in eastern Turkey has been accommodated since the Miocene by westward escape of continental lithosphere between the North and South Anatolian transform faults. Neotectonic pull-apart basins formed in response to these movements, accumulating large thicknesses of Miocene-Pliocene carbonates and clastic sediments. Potential reservoirs in the Neotectonic basins may be sourced either in situ or from underlying Palaeozoic and Mesozoic source rocks that remain within the hydrocarbon generating window toda .

AAPG Search and Discovery Article #91003©1990 AAPG Annual Convention, San Francisco, California, June 3-6, 1990