Geological Structure of the Central Group of Islands of the Greater Kuril Ridge (Simushir, Rasshua, Yankicha, Ryponkicha Islands), Based on K–Ar Dating

This paper presents the first K–Ar dating results for Neogene–Quaternary igneous rocks in the Central Kuril Islands: Simushir, Rasshua, Ushishir (Yankicha and Ryponkicha islands). On Simushir Island, five age determinations were obtained: four from the Okruglovsky Volcanic Complex (5.7 to 3.0 Ma) and one from the Golovnin complex (0.75 Ma). On Rasshua and Ryponkicha, three determinations for the Levashov Volcanic Complex gave ages of 2.4 to 1.3 Ma. Rocks on Yankicha Island from the Golovnin complex were dated at 0.74 Ma.