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Compositional Trends at Bezymianny Volcano (1955-2008 eruptive period). Pavel Izbekov 1 and PIRE team 2. 1 Geophysical Institute, University of Alaska Fairbanks 2 http://gps.alaska.edu/PIRE/index.html. Historical perspective: JKASP was first.
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Compositional Trends at Bezymianny Volcano (1955-2008 eruptive period) Pavel Izbekov1 and PIRE team2 1 Geophysical Institute, University of Alaska Fairbanks 2 http://gps.alaska.edu/PIRE/index.html
Historical perspective: JKASP was first Building links between Russian, Japanese, and US geoscientists through series of meetings focusing on understanding and mitigating natural hazards in Northern Pacifica
Historical perspective: Int. Volc. School • Training opportunity for AVO students transformed to an internationally recognized for-credit class at UAF • Two 2-week sessions: The Valley of Ten Thousand Smokes, Alaska and Mutnovsky / Gorely, Kamchatka • ~50 students take the class per year
Partnership in International Research and Education (PIRE project) • NSF-funded multi-disciplinary comparative study of Bezymianny, Shiveluch, and Mount St. Helens providing an opportunity to US students to get involved in international scientific projects • ~50 students, faculty, and stuff currently active in the project
PIRE-Kamchatka: Scientific goal How an edifice collapse affects magma system of an active volcano and its following eruptive activity? What can we learn about Mount St Helens looking at its Russian analogs – Bezymianny and Shiveluch?
Mineral assemblage vs. time Hb Hb 0.4 mm 0.4 mm Hornblende core in a OPx-CPx-Mt aggregate of the May 9, 2006 andesite X X
What is the meaning of the observed compositional variations at Bezymianny?
Sequential withdrawal from the top of compositionally zoned magma system / column? Magma column goes backward?
Single basaltic injection in 1955? Requires effective but gradual admixture of mafic end-member to the 1956 magma. Convection of the crystal-rich magma would be problematic.
Repetitive / continuous basaltic injections through the 1956 magma body? What is the frequency of recharges? Before each eruption? What controls the composition of magma at the exit? What is the composition of the mafic end-member and where are the xenocrysts?