Research Information System
59.Türkiye Jeoloji Kurultayı, Ankara, Turkey, 20 - 24 March 2006, pp.58-59
The Pontides, as an Alpide tectonic unit of Turkey, is bordered by Black Sea in the north and İzmir – Ankara – Erzincan suture in the south. In a sense, the Pontides represent an orogenic mosaic that was developed by amalgamation of different pre-Alpine and Alpine units. This orogenic mosaic was formed mainly by superimposed orogenic events during Precambrian, Dogger, late Campanian and Lutetian periods. The boundaries and internal subdivisions of the Pontides were evaluated on a basis of Alpine, Tethyan or circum Black Sea events in previous researches. As a result of this, definition of Pontides and the internal subdivisions and their tectonic implications were not understood correctly due to the lack of a standard geological reference system. Because of this, Pontides was evaluated as either a main tectonic unit or a geographic entity in the literature. Recent field-based researches show that there are 3 main tectonic units in northern Anatolia; İstanbul Zone in the north, Sakarya Zone in the south, and Intermediate Zone (Armutlu-Ovacık Zone) between them. İstanbul and Sakarya zones were amalgamated before the Malm period and formed a unique tectonic entity. In this Alpine unit, the major geological event occurred during the early Cretaceous which developed Black Sea basin in the north and Intra-Pontide basin (Boyalı basin) in the south. As a consequence of early Cretaceous rifting the Sakarya Zone was divided into three fragments.