Earthquakes, characteristics of the upper mantle under kamchatka, and their connection with volcanism (according to data collected up to 1971)
- 38 Downloads
This paper presents new data on the upper mantle characteristics, and on seismicity and volcanism in Kamchatka.
It is shown that the seismic activity in the Pacific focal layer decreases sharply below that narrow line on which the foci of the active volcanoes are situated. A map of longitudinal wave velocitiesVp in the mantle upper layers under Kamchatka is given. The lowest values ofVp (7.3–7.6 km/sec) are found near the volcanic belt. The graphs Θ=lg (Es/Ep) (h) for the Kamchatka earthquakes indicate that Θmin at the depths of 120–250 km may be caused by a concentration of magmatic melts. A map of bodies (magma chambers?) screening S- and P-waves at the depths of 30–100 km under Kamchatka has been compiled. These bodies are mainly located under the belt of active volcanoes.
KeywordsSeismic Activity Volcanic Belt Active Volcano Energy Class Earthquake Focus
Unable to display preview. Download preview PDF.
- Balesta, S. T., 1967,An Example of Application of Point Seismic Soundings with Refracted Waves in Studying the Deep Structure of the Avachinsky Volcano. Geol. i Geofiz., no. 8, p. 93–97 (in Russian).Google Scholar
- Fedotov, S. A., 1966,Deep Structure, Upper Mantle Properties and Volcanic Activity in the Kurile-Kamchatka Island Arc According to Seismological Data for 1964. In: «Vulkanizm i glubinnoye stroyeniye Zemli», Izd. Nauka, Moscow, p. 8–24 (in Russian).Google Scholar
- -----, 1968,On Deep Structure, Properties of the Upper Mantle and Volcanism of the Kurile-Kamchatka Island Arc According to Seismic Data. In:The Crust and Upper Mantle of the Pacific Area. Geophys. Monograph No. 12, Washington, p. 131–139.Google Scholar
- ----- andBoldyrev, S. A., 1969,On Dependence of Body Wave Absorption on the Frequency in the Crust and Upper Mantle of the Kurile Island Arc. Izv. AN SSSR, ser. «Fizika Zemli», no. 9, p. 17–33 (in Russian).Google Scholar
- ————— andFarberov, A. I., 1966,On Screening of Transversal Seismic Waves and the Magma Chambers in the Upper Mantle beneath the Avachinskaya Volcanic Group. Sb. «Vulkanizm i glubinnoye stroyeniye Zemli», Idz. Nauka, Moscow, p. 43–48 (in Russian).Google Scholar
- ----- andSlavina, L. B., 1968,Estimated Velocity of Longitudinal Waves in the Upper Mantle under the Northwestern Part of the Pacific Ocean and Kamchatka. Izv. AN SSSR ser. «Fizika Zemli», no. 2, p. 8–31 (in Russian).Google Scholar
- Fedotov, S. A. andTokarev, P. I., Bagdasarova, A. M., Kuzin, I. P. andBobkov, M. F., 1969,Seismicity of Kamchatka and Komandor Islands and Its Connection with the Deep Structure of the Crust and Mantle. «Stroyeniye i razvitiye zemnoi kory na Sovetskom Dalnem Vostoke», Nauka, Moscow, p. 97–110 (in Russian).Google Scholar
- Firstov, P. P. andShirokov, V. A., 1969,Localization of the Roots of the Klyuchevskaya Volcanic Group According to Seismic Data. «Vulkanizm, gydrotermy i glybiny Zemli», D-V knizhnoye Izd-vo, Petropavlovsk-Kamchatskiy, p. 12 (in Russian).Google Scholar
- Tokarev, P. I., 1970,On the Focal Layer, Seismicity and Volcanism of the Kurile-Kamchatka Area. Izv. AN SSSR, ser. «Fizika Zemli», no. 3, p. 15–30 (in Russian).Google Scholar
- ----- andZobin, V. M., 1970,Peculiarities of the Near-earthquake Wave Propagation in the Earth’s Crust and Upper Mantle under the Kliuchevskaya Volcanic Group, Kamchatka. Bull. of the Volcanological Station, no. 46, Nauka, p. 17–23 (in Russian).Google Scholar
- Vlodavetz, V. I., andPiip, B. I., 1957,Catalogue of the Active Volcanoes of Kamchatka. Bull. of the Volcanological Station, USSR Acad. of Sci., no. 25, p. 5–95 (in Russian).Google Scholar