The significant variations in seismic parameters in the crust seem to
have a direct link with the eruptive activity of the volcanoes. The distribution of seismic velocities and V
p/Vs values allows the magma sources
beneath the volcanoes to be tracked in time and allows us to surmise
their role in volcanic activity. The major changes are observed in 2005
when eruptions of Bezymianny and Kluchevskoy occurred almost in
the same time. It is seen that Kluchevskoy is fed through a complex
system of intermediate reservoirs in the crust, while Bezymianny