Structure of the Subduction Zone and Volcanism in Kamchatka

The correlation of the parameters of a subducted plate with the volcanism is studied. The north-to-south increase in the age of a slab controls the dip angle, the slab motion rate, and the extent of seismofocal zones and is reflected in the evolution of volcanic belts. Pliocene–Quaternary volcanoes in the Central Kamchatka Depression are characterized by predominantly basic and intermediate compositions of magmas. In contrast, Neogene–Quaternary volcanism in Southern Kamchatka is characterized by strong explosions of acidic magmas. Transform faults account for plate heterogeneity, which is reflected in higher magma productivity relative to background values along the arc. Thus, there is a relationship between the magma compositions, heights of volcanoes, and depths of magma chambers.