Tectonic Development of Western Anatolian Extensional Province

Abstract

Western Anatolia is one of the fastest-extending continental regions. The approximately N-S extension, in three phases, generated grabens of various ages and trends. The first phase occurred during the late Oligocene-Early Miocene and caused the exhumation of the high-grade metamorphic rocks in the footwall of the low-angle detachment fault(s). This phase caused the NNE trending grabens, particularly in the northern areas. The second phase happened in the Late Miocene. The initial rise of the central horst (the Bozdag Horst) bounded by the detachment faults corresponds to this extension. The third phase generated the dominant morphotectonic entities of western Anatolia, the E-W trending normal faults, and the associated grabens in Quaternary. Western Anatolia began rotating counter-clockwise since the westerly escape of the Anatolian Plate reached the region and caused the generation of the NE-NW trending conjugated strike-slip faults and the consequent grabens along the coastal areas in the Holocene.