JOURNAL OF ASIAN EARTH SCIENCES, vol.23, no.2, pp.153-162, 2004 (SCI-Expanded)
Northwestern Anatolia contains different tectonic units which are presently bounded by the two branches of the North Anatolian Fault. The Pontide Zone in the north consists of the Istanbul-Zonguldak Unit to the west and the Ballidag-Kure Unit (a remnant of Paleo-Tethyan ocean) in the east. The Sakarya Zone in the south is juxtaposed against the Pontide Zone due to the closure of Paleo-Tethys. The Armutlu-Ovacik Zone represents a tectonic mixture of both zones in the north and south. Neotectonic units, such as the Izmit-Sapanca Corridor and the Northern Sakarya Low, which developed south of the Istanbul Zone and north of the Sakarya Zone, respectively, represent an extensional tectonic regime.