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 2016
Gordeev E.I., Girina O.A., Lupyan E.A., Sorokin A.A., Kramareva L.S., Efremov V.Yu., Kashnitskii A.V., Uvarov I.A., Burtsev M.A., Romanova I.M., Mel’nikov D.V., Manevich A.G., Korolev S.P., Verkhoturov A.L. The VolSatView information system for Monitoring the Volcanic Activity in Kamchatka and on the Kuril Islands // Journal of Volcanology and Seismology. 2016. V. 10. № 6. P. 382-394. doi: 10.1134/S074204631606004X.    Аннотация
Kamchatka and the Kuril Islands are home to 36 active volcanoes with yearly explosive eruptions that eject ash to heights of 8 to 15 km above sea level, posing hazards to jet planes. In order to reduce the risk of planes colliding with ash clouds in the north Pacific, the KVERT team affiliated with the Institute of Volcanology and Seismology of the Far East Branch of the Russian Academy of Sciences (IV&S FEB RAS) has conducted daily satellite-based monitoring of Kamchatka volcanoes since 2002. Specialists at the IV&S FEB RAS, Space Research Institute of the Russian Academy of Sciences (SRI RAS), the Computing Center of the Far East Branch of the Russian Academy of Sciences (CC FEB RAS), and the Far East Planeta Center of Space Hydrometeorology Research (FEPC SHR) have developed, introduced into practice, and were continuing to refine the VolSatView information system for Monitoring of Volcanic Activity in Kamchatka and on the Kuril Islands during the 2011–2015 period. This system enables integrated processing of various satellite data, as well as of weather and land-based information for continuous monitoring and investigation of volcanic activity in the Kuril–Kamchatka region. No other information system worldwide offers the abilities that the Vol-SatView has for studies of volcanoes. This paper shows the main abilities of the application of VolSatView for routine monitoring and retrospective analysis of volcanic activity in Kamchatka and on the Kuril Islands.
Gordeev E.I., Girina O.A., Manevich A.G., Melnikov D.V., Nuzhdaev A.A. 2015-2016 Activity of Kamchatkan and Northern Kuriles Volcanoes (Russia) and Danger to Aviation // 9th Biennial Workshop on Japan-Kamchatka-Alaska Subduction Processes (JKASP 2016). Fairbanks, Alaska: UAF. 2016. P. 93-94.
Gordeev E.I., Loupian E.A., Girina O.A., Sorokin A.A. VolSatView Information System Capabilities for Studying Kamchatka and Northern Kuriles Volcanic Activity // Modern Information Technologies in Earth Sciences. Proc. of the VI International Conference, Yuzhno-Sakhalinsk, August 7-11, 2016. Vladivostok: Dalnauka. 2016. P. 19
Gordeychik Boris, Churikova Tatiana, Kronz Andreas, Simakin Alexander, Wörner Gerhard First data on magma ascent and residence times retrieved from Fe-Mg and trace element zonation in olivine phenocrysts from Kamchatka basalts // Geophysical Research Abstracts. 2016. V. 18. P. EGU2016-12839.    Аннотация
Compositional zonation in olivine phenocrysts and diffusion modelling have been used in the last ten years to estimate magma residence times and the duration of magma ascent. The fundamental assumption is that mixing with newly injected magma into a reservoir triggers diffusional exchange between mafic olivine crystals and more evolved magma and that this magma mixing eventually triggers eruption. If depth of mixing is known, this translates to ascent rates of magmas to the surface. We applied this approach to a series of different arc basalt lavas from Kamchatka to constrain the rates of magma ascent and magma resident in what is one of the most active subduction zones in the world that is also dominated by an abundance of unusually mafic magmas. Our sample collection cover the principal modes of arc magmatism in Kamchatka: from different volcanic complexes (stratovolcano, dikes, summit eruptions, monogenetic cones), of different age (from Late-Pleistocene to Holocene and recent eruptions), from different magmatic regimes (long-lived volcanoes vs. monogenetic eruptions) and different major element composition (from basalt to basaltic andesite of different geochemical character including LILE enrichments). We analyzed and modelled zonation profiles for a range of elements with different diffusivities (e.g. Mg-Fe, Ca, Ni, Mn, Cr) to assess the role of variable diffusivities as a function of major and trace elements in the olivines from different P-T conditions. First data were obtained on samples from the Klyuchevskoy, Shiveluch and Tolbachik, including recent most eruption in 2012/2013. These data show that for some samples the zonation patterns are much more complex than is usually observed: high-Mg olivines at different volcanoes have very different zonation patterns, including normally, reversely zoned grains or even show highly complex repetitive zonation that indicate large compositional changes in the surrounding magma at very short time scales (years). Thus in some Kamchatka basalts, we observe unusual Mg-Fe zonations that are linked to complex mixing, possibly resorption and subsequent crystal growth processes that are generally not preserved due to fast diffusion of Mg-Fe. Based on a first assessment of our measured profiles, the values for diffusion times in Fo-rich olivines (88 to 92% Fo) vary from only a few months to years and thus magma ascent from deep magma sources must have been fast.
Kalacheva Elena, Taran Yuri, Kotenko Tatiana, Hattori Keiko, Kotenko Leonid, Solis-Pichardo Gabriela Volcano–hydrothermal system of Ebeko volcano, Paramushir, Kuril Islands: Geochemistry and solute fluxes of magmatic chlorine and sulfur // Journal of Volcanology and Geothermal Research. 2016. V. 310. P. 118-131. doi:10.1016/j.jvolgeores.2015.11.006.    Аннотация
Ebeko volcano at the northern part of Paramushir Island in the Kuril island arc produces frequent phreatic eruptions and relatively strong fumarolic activity at the summit area ~ 1000 m above sea level (asl). The fumaroles are characterized by low-temperature, HCl- and S-rich gas and numerous hyper-acid pools (pH < 1) without drains. At ~ 550 m asl, in the Yurieva stream canyon, many hot (up to 87 °C) springs discharge ultra-acidic (pH 1–2) SO4–Cl water into the stream and finally into the Sea of Okhotsk. During quiescent stages of degassing, these fumaroles emit 1000–2000 t/d of water vapor, < 20 t/d of SO2 and < 5 t/d of HCl. The measurement of acidic hot Yurieva springs shows that the flux of Cl and S, 60–80 t/d each, is independent on the volcanic activity in the last two decades. Such high flux of Cl is among the highest ever measured in a volcano–hydrothermal system. Oxygen and hydrogen isotopic composition of water and Cl concentration for Yurieva springs show an excellent positive correlation, indicating a mixing between meteoric water and magmatic vapor. In contrast, volcanic gas condensates of Ebeko fumaroles do not show a simple mixing trend but rather a complicated data suggesting evaporation of the acidic brine. Temperatures calculated from gas compositions and isotope data are similar, ranging from 150 to 250 °C, which is consistent with the presence of a liquid aquifer below the Ebeko fumarolic fields. Saturation indices of non-silicate minerals suggest temperatures ranging from 150 to 200 °C for Yurieva springs. Trace elements (including REE) and Sr isotope composition suggest congruent dissolution of the Ebeko volcanic rocks by acidic waters. Waters of Yurieva springs and waters of the summit thermal fields (including volcanic gas condensates) are different in Cl/SO4 ratios and isotopic compositions, suggesting complicated boiling–condensation–mixing processes.
Khubunaya S.A., Eremina T.S., Sobolev A.V. The classification of potassium basaltic trachyandesites that were discharged by the 2012–2013 parasitic eruption on Ploskii Tolbachik Volcano, Kamchatka using geochemical criteria // Journal of Volcanology and Seismology. 2016. V. 10. № 1. P. 33-49. doi: 10.1134/S0742046316010024.    Аннотация
Abstract—This study is concerned with the petrographic, mineralogic, and geochemical features in the K-high basaltic trachyandesites that were discharged by the 2012–2013 parasitic eruption on Ploskii Tolbachik Volcano. These K-high basaltic trachyandesites exhibit some obvious characteristics that testify to their suprasubduction origin. They are deeply differentiated rocks with strongly fractionated plagioclase.A study of the Sr, Nd, and Pb radiogenic isotope ratios in the K-high basaltic trachyandesites provided evidence of their mantle origin and of the fact that the crust has exerted no influence on their compositions. We performed a comparative analysis of the ratios of the concentrations for some incoherent elements in the K-high basaltic trachyandesites, as well as in intraplate, riftogenic, and island-arc moderate potassium basalts and basaltic andesites in relation to the concentrations of these elements in the primitive mantle. The geochemical features of these K-high basaltic trachyandesites classify them as belonging to the suprasubduction subalkaline formation of the potassium series.

Изучены петрографические, минералогические и геохимические особенности К-трахиандезибазальтов побочного извержения 2012–2013 гг. вулкана Плоский Толбачик. К-трахиандезибазальты имеют явные признаки надсубдукционного происхождения. Это глубоко дифференцированные породы, характеризующиеся значительным фракционированием плагиоклаза. Изучение радиогенных изотопных отношений Sr, Nd и Pb в К-трахиандезибазальтах свидетельствует об их мантийном происхождении и отсутствии влияния земной коры на их составы. Проведен сравнительный анализ отношений содержаний некогерентых элементов в К-трахиандезибазальтов,внутриплитных,рифтогенных и островодужных умереннокалиевых базальтах и андезибазальтах к содержанию этих элементов в примитивной мантии. Геохимические особенности К-трахиандезибазальтов позволяют отнести их к надсубдукционной субщелочной формации калиевого ряда.
http://repo.kscnet.ru/2626/ [связанный ресурс]
Melnikov Dmitry, Malik N., Kotenko T., Inguaggiato Salvatore, Zelenski M. A New Estimate of Gas Emissions from Ebeko Volcano, Kurile Islands // Goldschmidt Conference. 26 June - 1 July, Yokohama, Japan. 2016. P. 2047    Аннотация
Concentrations and emission rates of major gas species were measured in August 2015 at Ebeko volcano, a quiescently degassing andesitic volcano on Paramushir Island, Northern Kuriles. Using mobile and scanning DOAS measurements we estimated SO 2 emission from the active crater of the volcano at 100 +36/-15 t/d. Based on the comparison of plume areas of individual fumaroles, ca. 90% of the total gas emission from Ebeko in 2015 was provided by a single powerful vent (" Active Funnel " fumarole) and the rest was shared among low-temperature fumaroles. At the time of measurements, gases from the main fumarole had temperature from 420 to 490 °C and composition close to the average arc gas [1], as shown in Table. Gas species CO2 SO2 H2S HCl H2O T, °C mmol/mol Main fumarole 27.9 23.5 6.1 5.6 936 420 Low-temp. jets 92.2 2.62 0.68 1.6 902 <120 Low-temperature fumaroles (<120 °C) emitted gas enriched in CO 2 (up to 28 mol%, 9.2 mol% on average). Such CO 2 enrichment together with depletion in HCl and sulfur species can be explained by scrubbing of soluble gas species by a well-developed hydrothermal system which discharges ultra-acid SO 4-Cl waters [2]. A weighted-average estimate of the total gas+vapor emission from the Ebeko summit provided 1470 t/d, which includes ~ 101 t/d SO2, ~ 110 t/d CO2, ~ 14 t/d H2S and HCl, and 1230 t/d of water vapour with > 50% of the magmatic component. The gas fluxes measured in August 2015 using DOAS fall into the range of previous measurements made from 1960 to 2012 that used direct methods [2] and correspond to the moderate degassing rate of the volcano.
Nishizawa T., Nakamura Hitomi, Churikova T., Gordeychik B., Ishizuka Osamu, Haraguchi Satoru, Miyazaki Takashi, Vaglarov Bogdan S., Ueki K., Toyama C., Iwamori Hikaru Geochemistry of high-Mg andesitic rocks in NE Kamchatka // V.M. Goldschmidt Conference, Yokohama, Japan, 26 June - 1 July 2016. Program and Abstracts. 2016. P. 2295    Аннотация
The northeast Kamchatka Peninsula is characterized by unique tectonic regimes: (i) the triple junction ~30 km off the east coast [1], (ii) subduction of the Emperor Seamount Chain [2], and (iii) possible asthenospheric flow between the mantle wedge and the sub-slab mantle via the edge of subducted Pacific slab [3]. Within this area, a monogenetic volcanic group occurs along the east coast, including high-Mg andesitic rocks and relatively primitive basalts (East Cones, EC [4]). We have conducted geochemical studies of the EC lavas, with bulk rock major and trace elements, Sr-Nd isotopic compositions, and K-Ar and Ar-Ar ages, based on which a possible contribution of subducted seamounts and its relation to the tectonic setting are discussed.
The elemental and isotopic compositions indicate that the lavas from individual cones have distinct mantle sources with different amounts and/or compositions of slab-derived fluids. Based on mass balance, water content and melting phase relations, we estimate the melting P-T conditions to be ~1200 ℃ at 1.5 GPa, while the slab surface temperature is 620 – 730 ℃ (at 50-80 km depth). The Sr-Nd isotopic compositions is close to Late Cretaceous Emperor Seamount Chain, especially Detroit [5]. The K-Ar and Ar-Ar ages of the Middle to Late Pleistocene are consistent with the present tectonic setting after 2 Ma [6].
These results suggest that the EC lavas including high-Mg andesite and basalt were generated by mantle flux-melting induced by dehydration of a subducted seamount inheriting a local thermal anomaly [7, 8]
Nishizawa Tatsuji, Nakamura Hitomi, Churikova T., Gordeychik B., Ishizuka Osamu, Iwamori Hikaru Genesis of Quaternary volcanism of high-Mg andesitic rocks in the northeast Kamchatka Peninsula // Japan Geoscience Union Meeting. 22-26 May 2016, Makuhari, Messe. 2016. P. SVC48-02.    Аннотация
Arc magmatism is a product of subduction factory, involving thermal and chemical interactions
between a subducted slab as a material input and mantle wedge as a processing factory. In turn, the
compositions of arc magma provide invaluable information concerning the material input and the
interactions. The northeast Kamchatka Peninsula is an ideal field to examine such interactions and
relationships, being characterized by (1) subduction of the Emperor Seamount Chain (Davaille and
Lees, 2004), and (2) possible material and thermal interaction among the subducted slab, the
overlying mantle wedge and the sub-slab mantle via the edge of subducted Pacific slab (Portnyagin
and Manea, 2008). Within this area, a monogenetic volcanic group occurs along the east coast,
including high-Mg andesitic rocks and relatively primitive basalts (East Cones, EC (Fedorenko,
1969)). We have conducted geochemical studies of the EC lavas, with bulk rock major and trace
elements, and K-Ar and Ar-Ar ages, based on which a possible contribution of subducted seamounts
and its relation to the tectonic setting are discussed.
The elemental compositions indicate that the lavas from individual cones have distinct mantle
sources with different amounts and/or compositions of slab-derived fluids. Based on mass balance,
water content and melting phase relations, we estimate the melting P-T conditions to bet ~1200 ℃
at 1.5 GPa, while the slab surface temperature is 620 –730 ℃ (at 50-80 km depth). Compared with
the southern part of Kamchatka, the slab surface temperature beneath EC seems to be high due to the
thinner Pacific slab associated with the seamount chain and/or the plate rejuvenation from a mantle
plume impact (Davaille and Lees, 2004; Manea and Manea, 2007).
The K-Ar and Ar-Ar ages of the Middle Pleistocene are consistent with the tephrochronological
study (Uspensky and Shapiro, 1984) and the present tectonic setting after 2 Ma (Lander and Shapiro,
2007). The high-Mg andesite with the highest SiO2 content in the EC lavas shows the oldest age
(0.73 ±0.06 Ma) within not only EC but also the northeast part of Kamchatka (e.g., Churikova et
al., 2015, IAVCEI). On the other hand, the rest of EC lava samples show relatively younger ages to
0.18 ±0.07 Ma. These results suggest that the EC lavas including high-Mg andesite and basalt were
generated by mantle flux-melting induced by dehydration of a subducted seamount inheriting a local
thermal anomaly (Nishizawa et al., 2014, JpGU; 2015, JpGU).

島弧火成活動はサブダクションファクトリーの産物で, それは沈み込んだスラブ(物質のインプット)-マン
トルウェッジ(加工工場)間の熱的・物質的相互作用を含む. 島弧マグマの組成は, その物質インプットと相
互作用について非常に貴重な情報をもたらす. カムチャツカ半島北東部はそのような相互作用と関係性を調べ
るうえで理想的な場所である, それは次のような特徴を有する為だ(1)天皇海山列の沈み込み(Davaille and
Lees, 2004)(2)沈み込んだスラブ, マントルウェッジと太平洋スラブエッジにかけてのサブスラブマントル
との物質的・熱的相互作用の可能性(Portnyagin and Manea, 2008). この地域の東海岸沿いに, 高-Mg安山岩
と比較的初生的な玄武岩を産出する単成火山群が確認されている(East Cones, EC(Fedorenko, 1969)).
我々はこのEC溶岩について全岩主要-微量元素組成分析とK-Ar, Ar-Ar年代測定を含む地球化学的研究を行い,
沈み込んだ海山からの寄与の可能性とテクトニックセッティングとの関係について議論する.
EC溶岩の組成は, 火山ごとに独立したソースに由来しており, そのソースの違いはスラブ起源流体の量および
またはその組成の違いによることを示す. マスバランス, 含水量, 相関係に基づき, 我々は溶融温度-圧力条
件を推定した, 溶融温度・圧力~1200℃, 1.5 GPa, スラブ表面温度 620-730℃(深度50-80 km). カム
チャツカ南部に沈み込むスラブ表面温度と比較すると, EC直下のスラブ表面温度は高く, これは天皇海山列に
沿ったプレートの薄化およびまたは沈み込む直前のプルームからの熱的効果による若返り効果によるものと考
えられる(Davaille and Lees, 2004; Manea and Manea, 2007).
K-Ar, Ar-Ar年代測定値は中期更新世で, これはテフラ層序学からの推定年代と一致し(Uspensky and
Shapiro, 1984), 2Ma以降現在のテクトニックセッティングに変化したこととも矛盾しない(Lander and
Shapiro, 2007). 最もSiO2含有量が高い高Mg安山岩は最古の年代を示し(0.73 ±0.06 Ma), これはECのみな
らずカムチャツカ北東部においても最も古いとみられる(e.g., Churikova et al., 2015, IAVCEI). 一方他
のECはより若い年代を示す(~0.18 ±0.07 Ma). これらの結果は以下のことを示す: 高Mg安山岩, 玄武岩を
含むEC溶岩は沈み込んだ海山による局所的な温度異常がスラブ起源流体の脱水を強めそれによって生じたフ
ラックス溶融によりもたらされた(西澤他, 2014, JpGU; 2015, JpGU).
Romanova I.M., Girina O.A., Maximov A.P., Vasiliev S.E. Integration of volcanological data in VOKKIA information system // Modern Information Technologies in Earth Sciences. Proc. of the VI International Conference, Yuzhno-Sakhalinsk, August 7-11, 2016. Vladivostok: Dalnauka. 2016. P. 65-66.
Sorokin A.A., Girina O.A., Korolev S.P., Romanova I.M., Efremov V.Yu., Malkovskii S., Verkhoturov A., Balashov I. The system of computer modeling of ash cloud propagation from Kamchatka volcanoes // 2016 6th International Workshop on Computer Science and Engineering (WCSE 2016). Tokyo, Japan: 2016. V. II. P. 730-733.
Sorokin A.A., Korolev S.P., Romanova I.M., Girina O.A., Urmanov I.P. The Kamchatka volcano video monitoring system // 2016 6th International Workshop on Computer Science and Engineering (WCSE 2016). Tokyo, Japan: 2016. V. II. P. 734-737.
Webley P, Girina O.A., Shipman J Remote Sensing Analysis of the 2015-2016 Sheveluch Volcano Activity // 9th Biennial Workshop on Japan-Kamchatka-Alaska Subduction Processes (JKASP 2016). Fairbanks, Alaska: UAF. 2016. P. 105-106.
Аникин Л.П., Блох Ю.И., Богданова О.Ю., Бондаренко В.И., Долгаль А.С., Долгая А.А., Жулёва Е.В., Малиновский А.И., Колосков А.В., Новиков Г.В., Новикова П.Н., Палуева А.А., Петрова В.В., Пилипенко О.В., Рашидов В.А., Романова И.М., Трусов А.А., Федоров П.И., Чесалова Е.И. Новые данные о строении подводных вулканов, гайотов и вулканических островов западной части Тихого океана // Материалы XIX региональной научной конференции «Вулканизм и связанные с ним процессы», посвящённой Дню вулканолога, 29 - 30 марта 2016 г. Петропавловск-Камчатский: ИВиС ДВО РАН. 2016. С. 3-11.    Аннотация
Приводятся новые данные о строении подводных вулканов, гайотов и вулканических островов западной части Тихого океана, полученные в рамках интеграции ученых различной специализации академической, вузовской и отраслевой науки в области наук о Земле при проведении комплексных геолого-геофизических исследований в 2015-2016 гг.
Артамонов А.В. Подводные горы системы поднятий Маркус-Неккер (Тихий океан): особенности строения и магматизма // Вестник КРАУНЦ. Серия: Науки о Земле. 2016. Вып. 31. № 3.    Аннотация
Проведенное сравнение особенностей вулканизма гайотов мелового возраста, расположенных в разных частях протяженной системы внутриплитных поднятий Маркус-Неккер в Тихом океане, выявило значительные различия в геохимических характеристиках, слагающих их пород, что указывает на существование латеральной и (или) вертикальной мантийной неоднородности в этом регионе. Исследованные вулканические породы относятся к щелочным сериям. В отдельных случаях, в них наблюдается низкие значения Na2O/K2O. Подобный вулканизм не характерен для большинства других внутриплитных поднятий Мирового океана. Отчетливых закономерностей между составом вулканических пород того или иного гайота, временем его формирования и (или) географическим положением не наблюдается. Незакономерное расположение разновозрастных подводных гор создает трудности при применении модели горячих точек для объяснения образования этой провинции внутриплитного магматизма. Положение подводных гор в структуре системы поднятий и всей этой системы в структуре дна Тихого океана не противоречит предположению об их связи с закономерной сетью разломных зон. Разломы способны инициировать плавление геохимически неоднородного верхнемантийного субстрата и приводить к формированию внутриплитных вулканических поднятий. Предполагается, что глубинные флюидные потоки могут быть еще одним фактором, приводящим к масштабному внутриплитному магматизму.

The paper presents geological and geochemical characteristics of Cretaceous guyots of Marcus-Necker intraplate rise in the Pacific Ocean. Comparison of guyots located in different parts of the extended system revealed significant differences in their geochemical characteristics, which suggest lateral and (or) vertical mantle heterogeneity in the region. The studied volcanic rocks belong to the alkaline series. In some cases, they exhibit low values of Na2O/K2O. This volcanism is not typical for most of intraplate ocean rises. No consistency is observed between volcanic rock composition of guyots, their age and (or) geographic position. A complex pattern of magnetic anomaly lineations and irregular location of seamounts of different age cause difficulties in applying hot spot model to explain the formation of this intraplate magmatic province. The location of seamounts in the structure of the rise system and the entire system in the structure of the Pacific Ocean does not contradict the formation of fault zones, which initiate melting of upper mantle geochemically inhomogeneous substrate and lead to the formation of intraplate rises. Deep fluid flows may cause a large-scale melting of the upper mantle.
Вулканизм, биосфера и экологические проблемы. Сборник материалов. VIII Международная научная конференция / Отв. ред. Волкодав И.Г. Майкоп – Туапсе: Изд-во «Магарин О.Г.». 2016. 288 с.
Галимов Э.М., Севастьянов В.С, Карпов Г.А., Шилобреева С.Н., Максимов А.П. Алмазы в продуктах извержения вулкана Толбачик (Камчатка, 2012–2013 гг.) и механизм их образования // Геохимия. 2016. № 10. С. 868-872. doi: 10.7868/S0016752516100034.    Аннотация
Происхождение алмазов, найденных в лаве и пепле недавнего извержения (2012–2013 гг.) вулкана Толбачик на Камчатке, загадочно. В минеральном составе вмещающих пород нет никаких признаков существования высокого давления, которое необходимо для образования алмазов. Мы изучили изотопный состав углерода алмазов и дисперсного углерода в лаве Толбачика, который мог служить субстратом для синтеза алмазов, и установили, что они схожи. Есть свидетельства того, что формирование алмазов Толбачика связано с динамикой флюида. На основании полученных результатов предполагается, что микроалмазы Толбачика образовались в процессе кавитации, возникшем при быстром движении вулканического флюида. Ранее нами была показана теоретическая возможность образования алмазов в процессе кавитации, и эта гипотеза была подтверждена экспериментально. Ультравысокое давление при кавитации создается в локальных точках (схлопывающиеся пузырьки); при этом давление окружающей среды не является определяющим для синтеза алмаза. Условия возникновения кавитации достаточно обычны в геологических процессах. Поэтому микроалмазы подобного происхождения могут быть распространены в природе гораздо шире, чем это предполагалось ранее.

The origin of diamonds in the lava and ash of the recent Tolbachik eruption of 2012–2013 (Kamchatka) is enigmatic. The mineralogy of the host rocks provides no evidence for the existence of the high pressure that is necessary for diamond formation. The analysis of carbon isotope systematics showed a similarity between the diamonds and dispersed carbon from the Tolbachik lava, which could serve as a primary material for diamond synthesis. There are grounds to believe that the formation of Tolbachik diamonds was related to fluid dynamics. Based on the obtained results, it was suggested that Tolbachik microdiamonds were formed as a result of cavitation during the rapid movement of volcanic fluid. The possibility of cavitation-induced diamond formation was previously theoretically substantiated by us and confirmed experimentally. During cavitation, ultrahigh pressure is generated locally (in collapsing bubbles), while the external pressure is not critical for diamond synthesis. The conditions of the occurrence of cavitation are rather common in geologic processes. Therefore, microdiamonds of such an origin may be much more abundant in nature than was supposed previously.
Галимов Э.М., Севастьянов В.С., Карпов Г.А., Шилобреева С.Н., Максимов А.П. Микрокристаллические алмазы в океанической литосфере и их возможная природа // Доклады Академии наук. 2016. Т. 469. № 1. С. 61-64. doi:10.7868/S0869565216190166.
Гирина О.А. Вулкан Безымянный: 60 лет со дня катастрофического извержения // Региональная XIX научная конференция «Вулканизм и связанные с ним процессы», посвящённой Дню вулканолога. 29-30 марта 2016 г., Петропавловск-Камчатский: ИВиС ДВО РАН. 2016.
Гирина О.А. Изучение вулканов Камчатки с помощью спутниковых данных высокого разрешения в ИС VolSatView // Сборник тезисов докладов. Четырнадцатая Всероссийская Открытая конференция «Современные проблемы дистанционного зондирования Земли из космоса», ИКИ РАН 14–18 ноября 2016 г. М.: ИКИ РАН. 2016. С. 308





 

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