Structural evolution of the Uşak–Güre supra-detachment basin during Miocene extensional denudation in western Turkey

Abstract

The Uşak–Güre basin is a NE–SW-trending extensional basin located in the northern part of the Menderes Massif, in western Anatolia. The Uşak–Güre basin contains a Lower to Upper Miocene volcano-sedimentary succession that records the unroofing of the metamorphic rocks of the Menderes Metamorphic Core Complex. We propose a new structural mechanism based on geological mapping and detailed kinematic fault analysis from each of the evolutionary phases. We also propose that north- to NE-dipping low-angle detachment surfaces define the basin boundaries and have identified three stages of deformation throughout the Miocene: the Early Miocene deformation phase (D 2 ) is characterized by low-angle normal faulting (Simav detachment fault) in the supra-detachment Uşak–Güre basin, which marks the initiation of the extensional tectonics during the latest Oligocene; the Middle Miocene deformation phase (D 3 ) refers to volcano-tectonic activities during accumulation of the İnay Group; the Late Miocene deformation phase (D 4 ) is related to late Miocene tectonic activity widely responsible for deposition of the Asartepe Formations and uplift of the metamorphic rocks in the Uşak basin margin. In addition, we propose that the eastern part of the Menderes Massif was delimited by the ‘Uşak–Muğla transtensional transfer zone’ from Middle Miocene time throughout the eastern part of the Menderes Metamorphic Core Complex.