DEPLETED VOLCANISM OF KUNASHIR ISLAND: THE ROLE OF NONSUBDUCTION FACTORS IN THE KURIL ISLAND-ARC MAGMATISM

Abstract

On the base of geochemical investigation of the main volcanites of Kunashir, Iturup and Paramushir islands (the three largest of the Kuril chain) it was attempted to estimate the respective roles of subduction and nonsubduction factors in petrogenesis of Kuril island arc basalts. Established is the substantial role of nonsubduction factors in magmogenesis of basalts, that is associated with the peculiar geodynamic conditions of Kuril and Japan island-arc systems' junction zone.