Cretaceous to miocene palaeogeographic evolution of Turkey: Implications for hydrocarbon potential

The Cretaceous to Miocene palaeogeographic development of Turkey in general reflects the evolution of the various oceanic branches of Neo-Tethys toget her with interactions between the Laurasian and Gondwanan margins. At the b eginning of the Cretaceous, the first-order palaeotectonic units which make up present-day Turkey either formed parts of these supercontinents or were isolated continental blocks within the Neo-Tethys. In Aptian to Albian tim es, north-dipping subduction commenced along the southern margins of these units and resulted in the development of magmatic arcs and are-related sedi mentary basins. Coeval with the start of subduction, large-scale ophiolite obduction occurred on the units' passive margins. Terminal closure of the o ceans' branches took place between the latest Cretaceous and the Miocene, f orming the Anatolian orogenic collage whose outline defines present-day Tur key. Post-collisional intra-continental convergence continued until the lat e Miocene and resulted in north-south shortening of the collage. This short ening led to internal imbrication, thrusting and crustal thickening It forc ed the Anatolian landmass westwards, away from east Anatolia where there ha s been continuous north-south compression since the Miocene between Laurasi a and the Arabian Platform. \Both the continental and the oceanic palaeotectonic units pose significant problems regarding their original geometry, size, depth, extent, contact r elations, motion paths, subduction polarity, stratigraphy and timing of for mation. Clarification of these issues is essential if the units' original p aleogeographic relationships with respect to Neo-Tethys ave to be reconstru cted. This paper reviews some of these problems with the aid of a number of palinspastic and non-palinspastic maps. These maps are intended to provide a basis for evaluating the hydrocarbon potential of Turkey.