The first results of tephrachronological researches of the Sarychev Peak volcano, the Matua Island, (Central Kuriles) are represented including the reconstruction of its eruptive history in the Holocene. Based on the study of the distribution of petrogenous oxides and microelements in the tephra sampled layer-by-layer from the reference section of soil-pyroclastic cover of Matua Island, a general trend of the geochemical evolution of the volcano products during the Holocene epoch is traced, their typification was made. The horizons of the transition ashes were identified.

На основе простой модели смешения, путем сравнения химического и изотопного состава газовых эмиссий с составами основных геохимических резервуаров в зоне субдукции, при ряде исходных допущений, рассчитан баланс флюидов вулкана Мутновский. Основу глубинного компонента (до 70–73% в наиболее горячих фумаролах) составляет слэб-флюид, отделяющийся при дегидратации Тихоокеанской плиты. Мантийная составляющая не превышает 2.1%. Доля газов континентальной коры может составлять от 0.5% до 5% в зависимости от принятого в расчетах конечного компонента. По составам газов Мутновский относится к типичным субдукционным вулканам, но имеет сложное строение флюидной системы. Наблюдаемое распределение составов фумарол вулкана объясняется дегазацией двух магматических тел.

The paper presents results from heat vision survey conducted at the following active volcanoes of the Kurile Islands during field works in 2009-2011: Golovnin and Mendeleev (Kunashir Isl.), Sarychev Peak (Matua Isl.), Ekarma (Ekarma Isl.), and Zavaritsky (Simushir Isl.). The paper contains thermogramms made after eruptions of Sarychev Peak in 2009 and Ekarma in 2010. Methods of heat vision survey and processing of infra-red images are described.

The paper presents the results of Brouton Bay (Simushir Island, the Kurile Islands) echo-sounding
investigations had been made in July 2011 during complex scientific and research expedition of FSBSO
Institute of Marine Geology and Geophysics FEB RAS by means of «Lowrance LMS-527cDF iGPS» echo
sounder with oscillator frequency of 50/200 kHz and built-in 12-channel GPS receiver. We worked out
57 km of depth sounding profiles and constructed Brouton Bay bathymetric map and 3D-model. The bay
maximum depth comprised 250 m and the caldera total depth comprised about 700 m. Submarine slopes
of the bay have an angle ~ 15-25° to the depths of 200-220 m, then they have an angle of 5-10°to the vast
nearly flat bottom at the depths of 240-250 m.

Abstract—We discuss the water!level variations in the E!1 well for the time period between May 2006 and
2010, inclusive. A trend towards an increasing level at an abnormally high rate occurred from mid!2006 to
December 2009. This increase is regarded as the response of the aquifer of gas!saturated ground water that
exists in the volcanogenic–sedimentary deposits of the Avacha volcano!tectonic depression to volumetric
strain changes during the precursory period and the occurrence of a swarm of small earthquakes ( = 8.3)
in the area of Koryakskii Volcano and to its phreatic eruption. We estimated the volumetric compression as
Δε = –(4.1 × 10–6–1.5 × 10–5) from the amplitude of water!level rise using the elastic parameters of the wa!
ter!saturated rocks. While the strain source was active, we observed a decreasing sensitivity of the hydrologic
regime in the well to the precursory processes before large (M ≥ 5.0) tectonic earthquakes.

The items of information about eruptions activity of Ebeko volcano in 2010-2011 are resulted. In 2010 from eruption funnel of Northern crater there were two weak short-term explosive eruptions. The eruption was phreatic, the cast out products are submitted by resurgent ashes. Volumes of the thrown out material ~ 1.2 t and ~ 95 t accordingly. All eruptions were anticipated by changes in chemical structure of fumarole gases, before eruption of July 2, 2010 the seismic harbingers were observed. In July, 2011 there was a series of hydrothermal explosions on the average crater of a volcano. The morphological changes have bottom and southwest wall of a crater. The maximal range ejection of ashes did not exceed 560 m.

Представлены результаты исследования лавовых потоков вулкана Безымянный различного возраста - от древних (около 3500 лет назад) до современных (1985-1989 гг.). Приводится подробная характеристика состава, строения и петрофизических свойств основных типов слагающих их пород - андезитов и андезибазальтов. Установлено, что главным фактором, определяющим свойства пород, является их пористость; влияние структурно-минералогических особенностей проявляется в меньшей степени. Показана динамика изменения свойств пород лавовых потоков в зависимости от их возраста: чем древнее породы, тем выше показатели их плотности и прочности и ниже значения пористости.

В работе даны краткая характеристика динамики извержения вулкана Кизимен от начала активизации до апреля 2012 г. и первые результаты петрохимического и минералогического изучения твердых продуктов извержения в 2011 г.