Here we present data on crystallization conditions of Klyuchevskoy volcano magmas (Kamchatka) based on study of melt inclusions in olivine. All calculated methods are based on melts composition, for which crystallization degree, water content, temperature and pressure of crystallization were estimated. Primary Klyuchevskoy magmas start to crystallize at 1250-1300 °C temperature and 37-42 km depth, corresponding to the Moho depth beneath the volcano. We recognize different scenarios of fractionation for different types of Klyuchevskoy rocks. Parental magmas of high-Al basaltic andesites crystallize at low geothermal gradient ~20 °C/kbar from 40 to 20 km depths, which results in crystallization rate ~2.5 %/kbar. At depth less than 20 km, the rates of magma cooling and crystallization increase up to ~35-50 °C/kbar and ~10-20 %/kbar, respectively, which suggest magma stalling beneath Klyuchevskoy. Magnesian basalts start to crystallize at the Moho depth and evolve along a nearly constant geothermal gradient ~20 °C/kbar and crystallization rate ~2.5 %/kbar up to shallow depths. These results are in good agreement with data on seismic tomography and suggest a complex and dynamically changeable magma-feeding system beneath Klyuchevskoy volcano. / Klyuchevskoy volcano, melt inclusions, parental melts conditions of crystallization, magma transport
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