1. Compositional Trends at Bezymianny Volcano (1955-2008 eruptive period) 1 Geophysical Institute, University of Alaska Fairbanks 2 http://gps.alaska.edu/PIRE/index.html Pavel Izbekov 1 and PIRE team 2

2. Historical perspective: JKASP was first

3. Historical perspective: Int. Volc. School

4. Partnership in International Research and Education (PIRE project)

5. 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?

6. Mineral assemblage vs. time Hornblende core in a OPx-CPx-Mt aggregate of the May 9, 2006 andesite Hb 0.4 mm X X

7. Whole rock and matrix glass compositions

12. What is the meaning of the observed compositional variations at Bezymianny?

13. Sequential withdrawal from the top of compositionally zoned magma system / column? Magma column goes backward?

14. 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.

15. 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?