We have identified, and describe in this paper, a phase of multifactor natural catastrophism that has been the greatest during our era in Kamchatka, to be dated 0-650 A. D. Its chief components were. The last catastrophic eruptions to have occurred (a caldera-generating one at about 240 A. D., the pyroclastics volume being 18-19 km3 and a subcaldera one around 600 A. D. with the volume of lava and pyroclastics 9.5-10.5 km3) which were followed by irreversible relief changes over areas of hundreds of square kilometers and have affected rather injuriously many other environmental components. An exceptionally intensive activity of the other volcanoes (at least 75-80% of all active and potebtially active Kamchatkan volcanoes were erupting, tens of large and catastrophic eruptions occurred). Regional catastrophic and large ashfalls. A sharp, large-amplitude (between 1.5-2 and 12-15 m) tectonic uplift of various blocks in Kamchatka. Large earthquakes accompanied by large-volume rockfalls, landslides, large and frequent tsunamis. The catastrophic events of that time are argued to have been part of a worldwide phase of natural catastrophism that we hypothesize to have occurred at the beginning of our era.

We studied the tectonic setting, morphology, geological structure, the history of eruptive activity and the evolution of the composition of the erupted material of Kizimen volcano (Kamchatka) from the moment of its origination (12-11 thousand years ago) to the present time. Four cycles 2-3,5 thousand years long each were distinguished that characterize the activity of the volcano. All largest eruptions were dated, their parameters determined. We also estimated the volume and the mase of the erupted products, volcanic intensity of evacuation of material during-periods of high activity and productivity of the volcano at different stages of its formation. It has been shown that evolution of the composition of the rocks erupted (from dacite to basaltic andesite) takes place as a result of mixing of dacitic and basaltic magma. It is proposed that future eruptions that may take place at Kizimen will be similar to those at Bandai (1888) and Mount St. Helens (1980) volcanoes.

Dynamics of the ongoing eruptive activity over the period 2010-2011 on Kizimen Volcano was reconstructed using aero-photo and satellite data. The geological and geomorphological impact of this activity was estimated. As a first approximation, the article provides estimates of degassing of volcano sulfur dioxide (as an index of the intensity of the volcanic processes) and the volume of a fresh lava flow.

The actual collective monograph presents the results of both theoretical and experimental studies of the multi-disciplinary problem on volcanic hazard assessment and development of techniques for prediction of catastophic eruptions. The volcanism of Kamchatka and other regions of Russia has been analyzed. On the basis of geological, volcanological and tephrachronological studies including radiocarbon dating, there have been defined certain groups of volcanoes on different stages of evolution. At the same time the problem of determination of the internal structure of volcanic dome using modem theoretical methods and technologies is well investigated. The new techniques of estimation of volcanic hazard were developed. Whenever ti is required, theoretical approaches are confirmed by results of in-field observations.

The book will satisfy the needs of Earth sciences specialists from a variety of backgrounds, volcanology, geo-mechanics, ecology, industrial constuction applications and hazard assessment.