Research on the colling speed of Dogansehir (Malatya) granitoid by the apatite fission track technique

The Doğanşehir (Malatya) granitoid is located in the Nappe Zone, which positioned in the northern part, the active margin, of the South Anatolian Orogenic Belt. The thesis study includes the apatite Fission Track analyses of the 6 samples taken from the northen part of the Doğanşehir granitoid where the Malatya-Ovacık Fault (MOF) cuts the unit. The MOF is activated at 5-3 Ma ago and currently still active. The samples taken from the fault zone show no age-elevation relation, indicating that the tectonic controlled unroofing/cooling in the region. The measured oldest age is 30.4±1.3 Ma, whereas the youngest is 12.6±0.9 Ma. The data obtained in this study indicate that the exhumation of the Doğanşehir granitoid by tectonic denudation, related to continent-continent collision may initiated at pre-Oligocene. The cooling profiles based on track length data indicate a fast cooling regime was dominant in the region especially during latest Miocene.