Stratigraphic Revision of the Selendi, Güre, and Uşak Neogene Basins, Western Anatolia

Abstract

In a re-examination of the Neogene stratigraphy of the U & scedil;ak, G & uuml;re, and Selendi basins of western Anatolia, western Turkey, the stratigraphic position of the previously defined & Idot;nay Group is revised, which was previously considered to be of the Middle Miocene age. Based on mammalian biochronology and stratigraphic relationships, two sequences are identified, separated by conformable/transitional contacts within the former group: the Middle Miocene G & uuml;re Group is composed of the Fak & imath;l & imath; Formation, characterized by alluvial fan deposits, and the lacustrine Derbent Formation. Radiometric dating of alkaline volcanics laterally associated with G & uuml;re Group sediments in the U & scedil;ak and G & uuml;re basins, and mammalian fossils re-evaluated into the MN5-6 biozones in the Selendi Basin, indicate early Middle Miocene. Considering the stratigraphic relationship with the overlying early Late Miocene & Idot;nay Group as redefined, we estimate that the G & uuml;re Group was deposited in the Middle Miocene. The & Idot;nay Group is characterized by a lateral-vertical transition from alluvial deposits of the Ahmetler Formation to the overlying lacustrine Ulubey Formation. An MN9-10 fauna, containing deinotheres, was found within the latter formation.