© Ya. D. Muravyev

Institute of volcanology & seismology RAS,
Piyp Boulevard, 9, Petropavlovsk-Kamchatsky, Russia,
e-mail: muryd@kscnet.ru

Together with glacial, meteorological and seismic reasons of Kolka glacier descent from its receptacle, we assume that volcanic (or postvolcanic) phenomena take part in the catastrophic development of this process.
Presence of volcanic-techtonic conditions for accumulation and advance to the day surface of great quantity of volcanic gases which include CO2, H2S and SO2 in various proportions; resemblance of phenomena which accompany explosive character of gas exit into environment in volcanic regions and similar displays in Kolka glacier canyon; as well as qualitative sensations of eye-witnesses - all these facts testify the possibility of explosive activity under the glacier, and it is genetically connected with glacier body dynamics.
Perhaps, another factor (which is not the last in the list of important ones) that had caused catastrophic character of Kolka glacier descent is the process in the geothermal system which is located in the fissure zone of deep fracture in Kolka canyon and this system is connected with Kazbek magmatic chamber and/or with neointrusions of the region.
Basing upon these premises we offer a hypothesis of recurring gas eruptions on the Kolka glacier bed. Taking it into consideration, we can explain some peculiarities of glacial catastrophe development both in this valley and in some other glaciers of Kazbek-Gimaraisky volcanic massif.