The Ziminy Sopki Volcanic Massif is remarkable for its co-formation from magmas of different potassium alkalinity manifested by three rocks associations (series) with individual evolutional trends: I — andesite-basalts — andesites — dacites; II — andesite-basalts — the intermediate composition andesites; III — high potassium andesite-basalts. Variations of rocks from the revealed series manifest themselves in the above mentioned mineral associations, and the discreteness of rocks regression lines evidence on quite autonomous parental magmas. Orthogonal trends of minerals composition alterations in andesite-basalts with the vector correlating with the potassium alkalinity increase in rocks of associations evidence on existence of the process leading to the enrichment of these magmas with potassium. Thus, we can conclude that, within the single penetrated magmatic system, there are deep intermediate chambers with different conditions for formation of the initial andesite-basalt magmas, which during volcanic activity directly associated with the deeper parental basaltic magma.

The paper describes petrophysical changes of Neogene-Quaternary volcanic rocks from Mutnovsky volcanic region under the action of hydrothermal processes. It was concluded that hydrothermal alterations lead to remarkable changes of physical and mechanical properties of rocks however the tendency of properties variation is different depending from a number of factors. Propylitization causes rocks consolidation, hardening, an increase of elastic properties, a decrease of porosity and disappearing of hygroscopic moisture. The influence of low-temperature fluids on the rocks is not so unequivocally. There can be a decrease as well as an increase of petrophysical properties. The sharp difference by properties, the structure of pore-space and the character and speed of hydrothermal alterations is observed between lavas and volcaniclastic rocks. However the primary differences between these rocks can disappear due to an intensive hydrothermal activity.

The Kamchatka branch of geophysical survey of RAS (KB GS RAS) is carry out a monitoring of activity of active volcanoes with the purpose of estimation of volcanic danger. One of the sections of observations is the satellite monitoring of thermal anomalies and ash plumes. They are based on a treatment and interpretation of satellite data information of AVHRR sensor of NOAA 16 and 17 satellites. The seismic monitoring is the main parameter for the volcano eruptions precursor as the most informative and authoritative method, because the quality of the seismic data is independent of the weather conditions. The seismic monitoring of the Bezymianny volcano is sometimes impossible or wrong. For the technical reasons or when strong seismic activity at the Klyuchevskoy volcano obscures the seismic data for the Bezymianny. So, the satellite monitoring of the thermal anomalies and research of its parameters are allows us to make a short-dated forecast for the Bezymianny volcano eruptions. The main aim of this article is an investigation of the thermal anomalies temperatures as a short-dated precursor for the Bezymianny volcano eruptions. There were 10 eruptions of the Bezymianny volcano in 2002-2007. The "normal", "higher" and "emergency" levels of anomaly temperatures with an allowance for the seasons of the year were separated. We separated such forecasting anomalies temperature values: "normal level" - is a temperature range, wherein the volcano activity on the ground level; "higher level" - is a temperature range, wherein the volcano prepare for any event (large rock fall, ash plume or eruption); "emergency level" - is temperature range, wherein the eruption will happen in the next 1-4 days. There are some criteria were mark out as a results of our researches. These criteria allow us to know the current status of volcano in presence using satellite data. The got information is compared with seismic, visual and video data, that allows us to trace the process of preparation of volcano to eruption much high-quality. The research results of the thermal anomaly temperatures are using as a secondary parameter to the seismic data for the Bezymianny volcano eruption precursor.

The paper presents data on the petrography, chemical and mineral composition of magnesian basalts (MgO content may reach 9 mass %) of Men'shii Brat volcano (Medvezh'ya caldera, Iturup Island, The Kuril Island Arc). The content of magnesian basalts and andesitic basalts in the front and axial zones of the Kuril Island Arc is very low. The article provides detailed data on the chemical composition of the rock-forming and accessory minerals (olivine, plagioclase, orto- and clinopyroxene, chromous spinel). High magnesian content, a peculiar composition of minerals (insets), olivine (Fo89-92) and chromous spinel (Kmg»50) associations allow concluding that the initial melts have a primitive nature.

This is the first paper presenting the case study for the active Koryaksky and Klyuchevskoy Volcanoes that shows the temporal relationship between the volcanic earthquakes (the volcanic EQ) and strong tectonic earthquakes (the tectonic EQ) in the world with Мw ≥ 6.3 at the final stage (less than a week) of their preparation (regardless the epicenters and depths of the tectonic EQ). The article shows that in 2009 the volcanic EQ at Koryaksky Volcano occurred 3 days prior to the tectonic EQ in the world and their number was in general anomalously high. 12 of 18 volcanic EQ alerted about the strong world events 3 days prior to the tectonic EQ. In 2008-2009 such effects typical for Klyuchevskoy Volcano as well, were used along with the other forecasting anomalies (including the deformation monitoring) for real-time forecast of the strong tectonic EQ in the world with the delay time equal to 6 days.

On the basis of the original materials obtained since 1978, the authors examine soil and vegetational cover within the zone of the strongest basalt eruption in Kamchatka. An intense ashfall in the summertime of 1975 caused the fall of enormous quantity of volcanites (0.7 km3). The ashfall destroyed vegetational cover over 100 km2 and damaged it over even larger territory. We consider the vegetational cover that existed prior to the eruption, the impact of the ashfall on the forest and alpine vegetation, and unclosed vegetation of the old lava flows. We calculated the area of the damaged vegetational cover and revealed the damage factors. The authors compared the damage factor of the vegetational cover caused by other ashfalls of the last century in Kurile-Kamchatkan region. Regional soils were studied for the first time.