STRATIGRAPHIC AND STRUCTURAL DEVELOPMENT OF THE EASTERN PONTIDES, TURKEY

This paper describes the stratigraphic and structural development of the Eastern Pontides, North Turkey, based on section logging at eight localities, construction of three structural profiles across the mountains, and published literature. The Eastern Pontides comprise a Late Carboniferous to Miocene sequence resting on a basement of Hercynian metamorphics. Late Carboniferous to Scythian sediments are continental clastics interpreted as having been deposited in an extensional half graben. The Middle Triassic is limestone, reflecting the development of a south facing passive margin. In the Late Triassic, the ocean (Palaeotethys) began to close: flysch was deposited in most places with minor shallow water limestones in the Sinemurian above an inverted half graben. All pre-Aalenian strata were deformed during the Cimmerian orogeny. After a phase of subduction-related volcanism in the Mid-Jurassic, limestones were deposited during the Late Jurassic and early Cretaceous, mainly in shallow water. The Aptian and Albian are absent due to doming in the Western Pontides prior to the opening of the Western Black Sea, but there is a thick sequence of Upper Cretaceous are volcanic rocks and intervening turbidites. The Upper Palaeocene is absent, possibly due to rifting in the Eastern Black Sea. Major compression affected the Pontides from the Eocene to the Pliocene associated with the closure of the Tethyan Ocean. Oligocene and younger rocks are accordingly non-marine.