Three volcanic islands of the South Aegean arc, representing a 25km across-arc setting, will be studied petrologically and geochemically studied will improve our understanding of the different sources and processes contributing to magma genesis in continental subduction zone settings. This will be achieved through study of thin sections, chemical whole rock analyses (ICP-OES, ICP-Q-MS, MC-ICP-MS) and mineralogical analyses (SEM-EDS and LA-ICP-MS).