Инд. авторы:	Artamonova S., Shevko E., Shevko A., Gora M., Bortnikova S.
Заглавие:	Uranium and thorium in the area of Mutnovskii and ebeko volcanoes (Far East of Russia)
Библ. ссылка:	Artamonova S., Shevko E., Shevko A., Gora M., Bortnikova S. Uranium and thorium in the area of Mutnovskii and ebeko volcanoes (Far East of Russia) // International Multidisciplinary Scientific GeoConference Surveying Geology and Mining Ecology Management, SGEM. - 2015. - Vol.1. - Iss. 1. - P.515-520. - ISSN 1314-2704.
Внешние системы:	SCOPUS: 2-s2.0-84952991187; SCOPUS: 2-s2.0-84946398612; WoS: 000371662300065;
Реферат:	eng: The goal of our research was to study the distribution of U, Th in the components of Mutnovskii and Ebeko volcano systems (the Pacific margin, Far East of Russia). The samples of effusive rocks and in their altered ones, sulfur fumaroles, mud pool water were studied. The synchrotron radiation X-Ray fluorescence analysis (SR-XRFA) and mass spectrometry with inductively coupled plasma (ICP-MS) were used. A wide range of volcanic rocks was involved in the study: basalt – andesitic basalt – andesite – dacite – rhyolitic dacite. SiO2 content increases from about 50 % (in basalt) to 76 % (in rhyolitic dacite). The volcanic rocks were revealed to contain very low quantity of U (0.n–4.3 ppm) and Th (2–9.3 ppm). The distribution of U and Th is characterized by a regular pattern: with an increase in SiO2 content, U and Th concentrations in rocks were revealed to increase too. However, U concentration increases more intensively than Th concentration. So, the average Th/U ratio was revealed to decrease from 3.62 in basalt to 1.57 in rhyolitic dacite. There are some varieties of Th and U distribution in different volcano systems: their concentration in the samples from the Ebeko area was determined to be usually larger than that in the samples from the Mutnovskii area. Due to the chemical peculiarities, uranium is more fluent than thorium. So, hydrothermal alteration of fresh volcanic rock results in a decrease of U content in andesite by about 20-25 %. Also sulfur fumaroles are enriched with U, and average Th/U ratio in sulfur fumaroles is equal only to 1.32. Thus, the Th, U and Th/U ratio indicate matter alteration and migration, and they can be used to study magmatic, hydrothermal and weathering processes in volcano system. © SGEM2015.
Ключевые слова:	Thorium; Uranium; Volcano; Basalt; Clay alteration; Fluorescence; Inductively coupled plasma; Mass spectrometry; Rocks; Silica; Sulfur; Synchrotron radiation; Thorium; Uranium; Volcanoes; Weathering; Volcanic rocks; Weathering process; Synchrotron radiation X-ray fluorescence; SR-XRFA; Rhyolitic; Regular patterns; Pool water; Hydrothermal alterations; Geochemical indicators; Geochemical indicator; Effusive rock;
Издано:	2015
Физ. характеристика:	с.515-520