The results of geological and geophysical studies, including recent ones, which make it possible to verify the existence of a liquid magma chamber below the Avachinsky volcano on Kamchatka, and to estimate the chamber depth and approximate dimensions, are analyzed. The heat stored in the host rock heated by the volcanic magma chamber from the time of chamber origination to the present is estimated, taking variable chamber dimensions during the process of evolution into account. The geological-geophysical prerequisites for using the thermal energy of the heated rock which surrounds the magma chamber to supply heat and power to Petropavlovsk-Kamchatskii are analyzed. The creation of an underground geothermal circulation system (fracture heat exchanger) using deep boreholes is proposed.

Изучение магматических питающих систем вулканов, корней вулканов, является одной из основных задач вулканологии. К числу главных объектов таких исследований принадлежит Ключевская группа вулканов (КГВ) наиболее мощная на островных дугах и в зонах поддвига литосферных плит. Сообщается о всесторонних исследованиях, которые ведутся здесь с 1931 г. Приводится ряд показательных результатов, полученных с 1960-х годов при изучении источников магм, извержений, землетрясений, деформаций и глубинного строения КГВ. При их рассмотрении учитываются данные физической вулканологии о механизме вулканической деятельности и данные петрологии о формировании магм. В магматической питающей системе КГВ и ее геофизической модели выделяются следующие пять частей: источник энергии и вещества у верхней границы тихоокеанского сейсмофокального на глубине около 160 км, область подъема магм в астеносфере, область накопления магм в коромантийном слое на глубинах 40-25 км, магматические очаги и каналы в земной коре, основания построек вулканов. Рассматриваются и объясняются свойства, связь этих частей, механизм деятельности вулканов и магматической питающей системы КГВ в ее современном состоянии. Имеются способы расчета магматических каналов, очагов, количества магмы в системе и других ее свойств.

Kizimen Volcano began to erupt in December 2010. The eruption was preceded by a precursory period of seismicity that lasted for 20 months. This paper discusses the space-time features of the precursory seismicity. We provide a brief description of this explosive and effusive eruption between December 2010 and March 2013. The eruption started with some explosive activity followed by extrusion of a viscous lava flow. The extrusion of viscous andesitic magma and the motion of the lava flow down the slope were accompanied by unusual seismicity in the form of the quasiperiodic occurrence of microearthquakes, the so-called drumbeat phenomenon. It is shown that the occurrence of a drumbeat was first recorded during the extrusion process at the volcano's summit. Subsequently, the drumbeat mode of activity was caused by the front of the viscous lava flow as it was moving down the slope. The dynamic parameters of the microearthquakes varied in accordance with the dimensions of the lava flow front. The motion of the main tongue of the lava flow (March to September 2011) gave rise to drumbeat I with energy classes of microearthquakes K = 3-5.5, while the second tongue, which was smaller than the first, produced drumbeat II with microearthquakes of K < 3 during its motion down the slope. In January 2013 we saw a phenomenon similar to the drumbeat that was recorded at the start of the eruption. This was caused by an obelisk being extruded at the volcano's summit. В© 2014 Pleiades Publishing, Ltd.

This paper is concerned with the geological history and petrology of a major polygenic volcanic edifice dating back to Upper Pleistocene to Holocene time. This long-lived volcanic center is remarkable in that it combines basaltic and trachybasaltic magmas which are found in basaltic andesite and trachybasaltic– trachyandesite series. The inference is that the coexisting parent magmas are genetically independent and are generated at different sources at depth in an upper mantle volume. The associated volcanic rocks have diverse compositions, stemming from a multi-stage spatio–temporal crystallization differentiation of the magmas and mixing of these in intermediate chas.