Characteristic Features of the Volcanism of the Siberian Platform

Widespead volcanism is characteristic of the Siberian platform, and was especially intense during uppermost Paleozoic and lower Mesozoic time. The Siberian traps, which occupy an area of more than 1,500,000 km^2, are best developed there. These are effusive and hypabyssal rocks of basalt-dolerite type, closely resembling trap rocks in other parts of the globe, especially the Karroo dolerires of South Africa

On the Magma Chambers beneath Klyuchevskoi Volcano, Kamchatka

AAbstract—Numerous summit and parasitic eruptions of moderate potassium magnesian and high-alumina basalts and basaltic andesites, their mineralogic and geochemical features, and the composition of in situ chilled melt inclusions in the olivine of cinder lapilli discharged by Klyuchevskoi Volcano all provide evidence of the presence of magma chambers beneath the volcano. This is also supported by a dualism in the variation of CaO and A1203 concentrations in olivine and clinopyroxene during crystallization. The mineralogic features in the high-alumina basalts that were discharged by all parasitic eruptions of Klyuchevskoi provide evidence of magnesian magma being emplaced from a deeper chamber into a shallow high-alumina chamber. The distribution of incoherent elements in the volcano's magnesian and aluminiferous rocks shows that they came from a single mantle source. The geochemical and mineralogic data are in good agreement with the results of geophysical surveys that concern the structure and properties of the lithosphere beneath Klyuchevskoi

Advanced method of scintillator energy resolution test

This work is devoted to the development of advanced method of scintillator energy resolution test. Separation of scintillation photons for different groups in accordance with statistical methods allows to extract some groups of photons that give better resolution values comparing to conventional approach. It is shown that new method could be useful for analysis of scintillation uniformity of detector

Lithospheric mantle beneath the south-eastern Siberian craton: Petrology of peridotite xenoliths in basalts from the Tokinsky Stanovik

We provide petrographic, major and trace element data for over 30 spinel peridotite xenoliths from the Tokinsky Stanovik (Tok) volcanic field on the Aldan shield to characterize the lithospheric mantle beneath the south-eastern margin of the Siberian craton, which formed in the Mesoproterozoic. High equilibration temperatures (870-1,010°C) of the xenoliths and the absence of garnet-bearing peridotites indicate a much thinner lithosphere than in the central craton. Most common among the xenoliths are clinopyroxene-poor lherzolites and harzburgites with Al2O3 and CaO contents nearly as low as in refractory xenoliths from kimberlite pipes (Mir, Udachnaya) in the central and northern Siberian craton. By contrast, the Tok peridotites have higher FeO, lower Mg-numbers and lower modal orthopyroxene and are apparently formed by shallow partial melting (<3 GPa). Nearly all Tok xenoliths yield petrographic and chemical evidence for metasomatism: Accessory phlogopite, amphibole, phosphates, feldspar and Ti-rich oxides, very high Na2O (2-3.1%) in clinopyroxene, LREE enrichments in whole-rocks. © Springer-Verlag 2005.SCOPUS: ar.jinfo:eu-repo/semantics/publishe