Peculiarities of Subduction in the Junction of the Kuril–Kamchatka and Aleutian Island Arcs

• Published in: Doklady Earth Sciences
• Main Authors: Gordeev, E., I, Koulakov, I. Yu., Shapiro, Nikolai, M, Ран, Академик, Гордеев, Е, И, Ран, Чл.-Корр, Кулаков, И, Ю, Шапиро, Н, М
• Other Authors: Institute of Volcanology and Seismology of the RAS, Far Eastern Branch of the Russian Academy of Sciences (FEB RAS), Schmidt United Institute of Physics of the Earth Moscow (IPE), Russian Academy of Sciences Moscow (RAS), Trofimuk Institute of Petroleum Geology and Geophysics of the Siberian Branch of the RAS (IPGG SB RAS), Siberian Branch of the Russian Academy of Sciences (SB RAS), Novosibirsk State University (NSU), Institut des Sciences de la Terre (ISTerre), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel-Université Grenoble Alpes (UGA)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2020
• Subjects: asthenosphere flow; seismic tomography; junction of the Kuril-Kamchatka and Aleutian island arcs; subduction; lithospheric plate; [SDU.STU]Sciences of the Universe [physics]/Earth Sciences; Aleutian Island; Kamchatka
• Online Access: https://hal.science/hal-03088528; https://hal.science/hal-03088528/document; https://hal.science/hal-03088528/file/gordeev2020_hal-03088528.pdf; https://doi.org/10.1134/S1028334X20100050

International audience The peculiarities of the junction between the Kuril-Kamchatka and Aleutian island arcs are studied using different techniques and experimental data. The models of medium structure that were obtained by using surface wave tomography and studies of S-wave anisotropy in the asthenosphere beneath the subduction plate detected an ascending asthenospheric flow of hot material and fluids along the northern boundary of the lithospheric plate. The presence of the ascending asthenospheric flow in the junction zone has been recently confirmed by detailed body-wave seismic tomography. Additional feeding of the Klyuchevskoi volcanic group from the asthenospheric flow explains the great difference in the eruptive activity of these volcanoes in comparison to other volcanoes located in the Eastern volcanic belt of Kamchatka. Comparative study of Quaternary volcanoes lying in the Eastern volcanic belt has revealed a strongly pronounced decreasing productivity from north to the south, i.e., with distance from the end of the subduction plate. This reduction is likely related to a depletion in the invasion of magmatic melts along the subduction plate from the asthenospheric flow in the junction of the Kuril-Kamchatka and Aleutian island arcs.