Textural and Compositional Evidence for Magma Mixing in the Evolution of the Camlidere Volcanic Rocks (Galatean Volcanic Province), Central Anatolia, Turkey

The Camlidere area, in the Galatean Volcanic Province (Ankara), Turkey, is composed of rhyolitic, andesitic, trachytic, dacitic and locally basaltic rocks. The older volcanic rocks in the studied area are rhyolitic and the younger ones basaltic. The phenocrysts from all the volcanic rocks exhibit some petrographic disequilibrium features such as: (a) coexistence of reversely, normally and oscillatory zoned sieved or unsieved plagioclase in the same rock; (b) wide compositional variation of An% in feldspar phenocrysts; (c) sieved, unsieved, normally and reversely zoned pyroxenes occur together in a single rock; (d) some orthopyroxene phenocrysts are surrounded by clinopyroxene; (e) reaction textures, and normal and reverse zoning of amphibole; (f) euhedral phenocrysts such as plagioclase, pyroxene coexist with resorbed phenocrysts of the same type.