Stratigraphic and structural development of the Eastern Pontides, Turkey

Abstract

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 arc 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.

Western versus Eastern Black Sea tectonic evolution: pre-rift lithospheric controls on basin formation

“…Rifting in the Eastern Black Sea probably began in the Late Paleocene with rotation of the Mid-Black Sea High away from the Shatsky Ridge-Caucasus (Russia). Extension and probable oceanic crust emplacement were complete by the Middle Eocene (Robinson et al, 1995a) and the Upper Paleocene to Recent postrift sequence is about 11 km thick.…”

Upper Campanian calciclastic turbidite sequences from the Hacımehmet area (eastern Pontides, NE Turkey): integrated biostratigraphy and microfacies analysis

“…The Şenköy and Berdiga formations are not exposed in the study area. The Upper Cretaceous is characterized by heterogeneous volcanic-sedimentary sequences, variable laterally and vertically due to syn-sedimentary tectonism and arc magmatism (Aydın et al 2008), deposited in a deep-marine environment (Robinson et al 1995). The Upper Cretaceous succession is subdivided into the Çatak, Kızılkaya, Çağlayan and Tonya formations.…”

Relative contributions of crust and mantle to generation of Campanian high-K calc-alkaline I-type granitoids in a subduction setting, with special reference to the Harşit Pluton, Eastern Turkey

“…It formed by north-dipping subduction under the Eurasian continental margin (e.g., Akin 1979;Ş engör and Yilmaz 1981;Okay and Ş ahintürk 1997;Yilmaz et al 1997;Ş engör et al 2003) and the subsequent collision between the Pontides and the Tauride-Anatolide platforms, although the timing of the collision is still controversial (e.g., Robinson et al 1995;Okay and Ş ahintürk 1997;Ş en et al 1998;Ş engör et al 2003). Okay et al (1997) suggested that the collision should date back to late Paleocene to early Eocene, based on field relationships and ages of granitoids.…”