The Ploskie Sopki volcanic massif: Geology, petrochemistry, mineralogy, and petrogenesis (Klyuchevskoi Volcanic Cluster, Kamchatka)

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

The state and prospects for the utilization of geothermal resources in the Russian Federation

The article presents the assessments of Russian geothermal resources and prospects of their development. The world experiences in the geothermal energy utilization have been analyzed. Based on numerous publications present classifications of geothermal resources have been considered, as well as advantage of their usage

The Tolbachik volcanic massif: A review of the petrology, volcanology and eruption history prior to the 2012–2013 eruption

The primary goal of this paper is to summarize all of the published data on the Tolbachik volcanic massif in order to provide a clear framework for the geochronologic, petrologic, geochemical and to a lesser extent the geophysical and tectonic characteristics of the Tolbachik system established prior to the 2012–2013 eruption. The Tolbachik massif forms the southwestern part of the voluminous Klyuchevskoy volcanic group in Kamchatka. The massif includes two large stratovolcanoes, Ostry (“Sharp”) Tolbachik and Plosky (“Flat”) Tolbachik, and a 70 km long zone of the basaltic monogenetic cones that form an arcuate rift-like structure running across the Plosky Tolbachik summit. The Tolbachik massif gained international attention after the 1975–1976 Great Tolbachik Fissure Eruption (GTFE), which was one of the largest eruptions of the 20th century and one of the six largest basaltic fissure eruptions in historical time. By the end of the GTFE, 2.2 km3 of volcanic products of variable basaltic compositions with MORB-like isotopic characteristics covered an area of > 1000 km2. During the following three decades more than 700 papers on various aspects of this eruption have been published both in national and international journals. Although the recent 2012–2013 eruption, which is the main topic of this volume, was not as long as the {GTFE} in duration or as large in area and volume of the erupted deposits, it brought to the surface a unique volcanic material never found before. In order to understand the data from new eruptions and make significant progress towards a better understanding of the Tolbachik magmatic system it is important to be able to put the new results into the historic context of previous research

Major and trace element zoning in plagioclase from Kizimen Volcano (Kamchatka): Insights into magma-chamber processes

The data on the geochemistry of the rocks of Kizimen Volcano and results of microprobe studies of major and trace elements in plagioclase grains from acid lavas and basalt inclusions are presented. The characteristics of the Kizimen Volcano are the following: (1) basalt inclusions are abundant in acid lavas; (2) banded, mixed lavas occur; (3) the distribution curves of rare earth elements of acidic lavas and basalt inclusions intersect; (4) Sr–Nd isotope systematics of the rocks and inclusions do not indicate mixture with crustal material; (5) plagioclase phenocrysts are of direct and reverse zonation; (6) olivine and hornblende, as well as acid and mafic plagioclases, coexist in the rocks. The studies revealed that the rocks are of a hybrid nature and originated in the course of repeated mixture of acid and mafic melts either with chemical and ther mal interaction of melts or exclusively thermal ones. Study of the major and trace element distribution in zonal minerals provides an informative tool for understanding the history of the generation and evolution of melts in a magma chambe