Analysis of the Spatial and Temporal Characheristics of Volcanism in Southern Kamchatka

Based on a comparison of different types of volcanoes, the volumes of igneous material, the geochemical characteristics of magma, and parameters of the Earth’s crust, we have analyzed volcanic activity in Southern Kamchatka. Thus, volumetric shields and complex volcanoes of Neogene–Pleistocene age are located in the rear of the arc, at a distance of ~273–283 km from the modern deep-sea trench. The active volcanic belt is located at a distance of 200–225 km from the deep-sea trench and is characterized by the predominance of caldera and complex volcanoes. The existence of areal monogenetic volcanism is recorded in the range of ~208–268 km from the deep-sea trench, indicating active extension processes, beginning in the Early Pleistocene–Holocene. The coexistence of felsic and mafic magmatism in the modern active volcanic belt suggests the potential for recharge of felsic magma chambers within the caldera complexes with mafic magmas in Southern Kamchatka. The geochemical zoning along the arc is poorly expressed in terms of incompatible and incoherent elements, which distinguishes Southern Kamchatka from the Eastern Volcanic Belt and the Northern Kuril Islands. Spatial and temporal characteristics reveal complicated processes of magma formation in the volcanoes of Southern Kamchatka compared to other segments of the Kuril–Kamchatka island arc.