Authors: Musa ALPASLAN, Durmuş BOZTUĞ
Abstract: The Upper Cretaceous-Paleocene plutons in the Yıldızeli region, emplaced in the crustal metamorphics of the Central Anatolian Crystalline Complex and covered by Lower Tertiary units, are referred to as Yücebaca and Davulalan Plutons. Davulalan Pluton is also intruded into Yücebaba Pluton. Yücebaba Pluton consist of granitic rocks with a K-feld+plg+qz+bi+sph+ap+ep+al+op mineralogical composition. Davulalan Pluton is composed of syenitic and quartz-syenitic rocks and, less frequently, of monzonitic and monzo-gabbroic dykes. Their mineralogical compositions are K-feld+per+qz+sph, K-feld+plg+bi+qz+sph+ap+ep+op, plg+K-feld+hst+di+sph+ap+op, and plg+K-feld+hst+ae-aug+op, respectively. Mineralogical and major-element geochemical data show that Yücebaca Pluton is S-type and peraluminous in character, whereas Davulalan Pluton is alkaline and has an alumino-cafemic composition. Major and trace-element data reveal the characters of Yücebaba and Davulalan to be syn-collisional and post-collisional, respectively. When the mineralogical-petrographical and geochemical characteristics are considered together with the space-time relations in the regional geological setting, the following petrogenetic models can be suggested for these plutons: Yücebaca Pluton is thought to have originated from anatexis in the thickened crust during collision, whereas Davulalan Pluton is assumed to have originated from a magma source which was produced by the partial melting of Upper Mantle material as a result of crustal attenuation during the tensional regime immediately after crustal thickening.