Neal C.A., Girina O.A., Ferguson G., Osiensky J. AIRBORNE ASH HAZARD MITIGATION IN THE NORTH PACIFIC: A MULTI-AGENCY, INTERNATIONAL COLLABORATION // Proceedings of the 2nd International Conference on Volcanic Ash and Aviation Safety, June 21-24, 2004, Session 2. Alexandria, Virginia (USA): 2004. P. 55
Neal C.A., Girina O.A., Senyukov S.L., Rybin A.V., Osiensky J., Hall T., Nelson K., Izbekov P. Eruption warning systems for aviation in Russia: a 2007 status report // 4th International Workshop on Volcanic Ash. Natural Hazards. New Zealand. 2007. 2007. P. 1-7.
Neal C.A., Girina O.A., Senyukov S.L., Rybin A.V., Osiensky J., Izbekov P., Ferguson G. Russian eruption warning systems for aviation // Materials of ISTC International Workshop “Worldwide early warning system of volcanic activities and mitigation of the global/regional consequences of volcanic eruptions”, Moscow, Russia, July 8-9, 2010. Moscow: ISTC. 2011. P. 29-47.
Neal C.A., Girina O.A., Senyukov S.L., Rybin A.V., Osiensky J., Izbekov P., Ferguson G. Russian eruption warning systems for aviation // Natural Hazards. 2009. Vol. 51. № 2. P. 245-262. https://doi.org/10.1007/s11069-009-9347-6.
More than 65 potentially active volcanoes on the Kamchatka Peninsula and the Kurile Islands pose a substantial threat to aircraft on the Northern Pacific (NOPAC), Russian Trans-East (RTE), and Pacific Organized Track System (PACOTS) air routes. The Kamchatka Volcanic Eruption Response Team (KVERT) monitors and reports on volcanic hazards to aviation for Kamchatka and the north Kuriles. KVERT scientists utilize real-time seismic data, daily satellite views of the region, real-time video, and pilot and field reports of activity to track and alert the aviation industry of hazardous activity. Most Kurile Island volcanoes are monitored by the Sakhalin Volcanic Eruption Response Team (SVERT) based in Yuzhno-Sakhalinsk. SVERT uses daily moderate resolution imaging spectroradiometer (MODIS) satellite images to look for volcanic activity along this 1,250-km chain of islands. Neither operation is staffed 24 h per day. In addition, the vast majority of Russian volcanoes are not monitored seismically in real-time. Other challenges include multiple time-zones and language differences that hamper communication among volcanologists and meteorologists in the US, Japan, and Russia who share the responsibility to issue official warnings. Rapid, consistent verification of explosive eruptions and determination of cloud heights remain significant technical challenges. Despite these difficulties, in more than a decade of frequent eruptive activity in Kamchatka and the northern Kuriles, no damaging encounters with volcanic ash from Russian eruptions have been recorded.
Nechaeva T.B., Kochegura V.V., Zubov A.G. Studies of secular paleomagnetic variations in Kamchatka using Holocene tephra // Volcanology and Seismology. 1984. Vol. 5. № 2. P. 213-218.
Проведено сравнение палеовариаций магнитного поля Земли, полученных по параллельным разрезам голоценового почвенно-пирокластического чехла вулкана Малый Семячик на Камчатке. Показано, что в интервале возраста 300 — 6000 лет назад наблюдается подобие изменений направления остаточной намагниченности подтверждающее первичность этой намагниченности и пригодность ее для реконструкции истории геомагнитного поля. Палеовариации, выделенные для интервала 1000 — 4000 лет назад, прослежены в одновозрастных слоях в 240 км к северу, в разрезе тефры Ключевского вулкана.
Выяснено, что вследствие связанной со спецификой формирования отложений тефры возможности выпадения из разрезов отдельных горизонтов для получения достаточно детальной картины палеовариаций необходимо изучение двух или более параллельных разрезов.
Рис. 6, библ. 3 назв.
Neill Owen K., Hammer Julia E., Izbekov Pavel E., Belousova Marina G., Belousov Alexander B., Clarke Amanda B., Voight Barry Influence of pre-eruptive degassing and crystallization on the juvenile products of laterally directed volcanic explosions // Journal of Volcanology and Geothermal Research. 2010. Vol. 198. № 1-2. P. 264-274. doi:10.1016/j.jvolgeores.2010.09.011.
Nekrylov Nikolay, Kamenetsky V.S., Savelyev D.P., Gorbach N.V., Kontonikas-Charos Alkiviadis, Palesskii Stanislav V., Shcherbakov Vasily D., Kutyrev Anton V., Savelyeva O.L., Korneeva Alina, Kozmenko Olga A., Zelenski Michael E. Platinum-group elements in Late Quaternary high-Mg basalts of eastern Kamchatka: Evidence for minor cryptic sulfide fractionation in primitive arc magmas // Lithos. 2022. Vol. 412. № 106838. P. 1-14. https://doi.org/10.1016/j.lithos.2022.106608.
The geochemical variations of magmas across and along supra-subduction zones (SSZ) have been commonly attributed to profound changes in the phase and chemical compositions of the mantle source and subduction-derived melt and fluid fluxes, as well as the physical parameters (e.g. depth, temperature, oxygen fugacity etc) of slab dehydration, mineral breakdown and melting. Here we test the variability of the Late Quaternary primitive magmas in the southern and northern parts of the meridionally oriented Eastern Volcanic Belt (EVB) of Kamchatka, with a slab depth varying from 60 to 160 km. Eight high-Mg (Mg# > 60 mol%) basalts were characterized for major, trace and platinum-group element (PGE) abundances, as well as the compositions of olivine phenocrysts and olivine-hosted spinel inclusions. The basalts in our study are geochemically typical of SSZ magmas and contain similar liquidus assemblages of forsteritic olivine (Mg# 78–92 mol%), low-Ti Cr-spinel and clinopyroxene. Although the absolute abundances of major and trace elements, and their ratios, in the basalts fluctuate to some extent, the observed variability cannot be correlated with any of considered parameters in the geometry of the Kamchatka SSZ and conditions of melting. This unexpected result led to the evaluation of the platinum-group element (PGE) systematics against the lithophile and chalcophile trace element geochemistry and the compositions of phenocrysts. Total whole-rock PGE content varies from 2.3 to 11.7 ppb, whereas the normalized PGE concentration patterns are typical for supra-subduction zones magmas and broadly similar in all studied samples. They are enriched in Rh, Pd and Pt relative to mid-ocean ridge basalts (MORB) and have nearly identical concentrations of Ir-group PGE. The only parameter that correlates well with PGE contents is the average Mg# of olivine phenocrysts from 84 to 90.3 mol%. This is interpreted to result from minor cryptic fractionation of sulfide melt, together with primitive olivine, in low-to-mid crustal conditions. Negative Ru anomalies on chondrite-normalized diagrams correspond to the Fe2+/Fe3+ ratios in spinel (a proxy for magma redox conditions), which reflects a replacement of monosulfide solid solution by laurite in the mantle wedge during oxidation.
Nemoto T. Geologic and petrologic study of the Central Kurile Islands, VI - Dzigoku Volcano, Urup Island // Bulletin of the Volcanological Society of Japan. 1937. Vol. 3. № 2.
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
The northeast Kamchatka Peninsula is characterized by unique tectonic regimes: (i) the triple junction ~30 km off the east coast , (ii) subduction of the Emperor Seamount Chain , and (iii) possible asthenospheric flow between the mantle wedge and the sub-slab mantle via the edge of subducted Pacific slab . Within this area, a monogenetic volcanic group occurs along the east coast, including high-Mg andesitic rocks and relatively primitive basalts (East Cones, EC ). 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 . The K-Ar and Ar-Ar ages of the Middle to Late Pleistocene are consistent with the present tectonic setting after 2 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 [7, 8]