The geoecological impact of eruptions on Karymskii Volcano and Tokareva crater, Eastern Kamchatka: The 1996-2008 observations

摘要

This paper considers the geoecological impacts of eruptions on Karymskii Volcano and the Tokareva crater for the 1996-2008 period, which resulted in changes in (a) the relief around these edifices, (b) the discharge and composition of water in the Karymskii River and other streams in the area, and (c) the discharge and composition of gases in thermal springs. It was found that the concentration of CH_4 previously had been abnormally high in free gases that emanate from the new Piipovskii Springs and an explanation is provided of the decrease in their concentration over time. We detected variations in the radon activity, OARn (Bq/m~3), in free gases that are released in the Karymskii caldera hydrothermal occurrences; the variations are consistent with those in the eruptive activity of Karymskii Volcano in 2005-2006. We describe permafrost rocks in the Karymskii caldera that favor the generation of a cryolithic zone.