The geological and geomorphic impact of catastrophic landslides in the Geyser Valley of Kamchatka: Aerial photogrammetry

We consider the results of the 19730-2008 aerial photogeodetic surveys conducted in the famous Geyser Valley of Kamchatka by the Institute of Volcanology (IV) of the Far East Division (FED) of the Russian Academy of Sciences (RAS), in 1973-1993, and by its successor, the Institute of Volcanology and Seismology (IV&S) FED RAS, in 2007-2008, in cooperation with the Chair of Photogrammetry at the Novosibirsk Institute of Engineers in Geodesy, Aerial Photograph Survey and Cartography (to be referred to here by the Russian abbreviation NIIGAiK), in 1973-1985. The aerial survey performed by the IV following Typhoon Elsa in October 1981 identified and recorded the typhoon-induced landslide that was the first to occur during the observation period in the east side of the valley. The measured area of landslide deposits is 28600 m 2 and its volume is 80000 m(3). An analysis of materials resulting from the July 12, 2007 aerial photograph survey was the basis for an objective evaluation of the impact of the June 3, 2007 catastrophic event in the Geyser Valley, for determining the qualitative and quantitative characteristics of the new landforms, and for a long-term forecast of future hazardous events and processes. It was concluded that the hazardous natural events and processes that have occurred in the past will undoubtedly occur in the future as well. For this reason the Geyser Valley should be constantly monitored using highly accurate geodetic and remote sensing techniques.