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Records: 21
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Carter A.J., Girina O.A., Ramsey M.S., Demyanchuk Yu.V. ASTER and field observations of the 24 December 2006 eruption of Bezymianny Volcano, Russia // Remote Sensing of Environment. 2008. Vol. 112. P. 2569-2577.
An explosive eruption occurred at Bezymianny Volcano (Kamchatka Peninsula, Russia) on 24 December 2006 at 09:17 (UTC). Seismicity
increased three weeks prior to the large eruption, which produced a 12–15 km above sea level (ASL) ash column. We present field observations from 27 December 2006 and 2 March 2007, combined with satellite data collected from 8 October 2006 to 11 April 2007 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), as part of the instrument's rapid-response program to volcanic eruptions. Pixel-integrated brightness temperatures were calculated from both ASTER 90 m/pixel thermal infrared (TIR) data as well as 30 m/pixel shortwave infrared (SWIR) data. Four days prior to the eruption, the maximum TIR temperature was 45 °C above the average background temperature (−33 °C) at the dome, which we interpret was a precursory signal, and had dropped to 8 °C above background by 18 March 2007. On 20 December 2006, there was also a clear thermal signal in the SWIR data of 128 °C using ASTER Band 7 (2.26 μm). The maximum SWIR temperature was 181 °C on the lava dome on 4 January 2007, decreasing below the detection limit of the SWIR data by 11 April 2007. On 4 January 2007 a hot linear feature was observed at the dome in the SWIR data, which produced a maximum temperature of 700 °C for the hot fraction of the pixel using the dual band technique. This suggests that magmatic temperatures were present at the dome at this time, consistent with the emplacement of a new lava lobe following the eruption. The eruption also produced a large, 6.5 km long by up to 425 m wide pyroclastic flow (PF) deposit that was channelled into a valley to the south–southeast. The PF deposit cooled over the following three months but remained elevated above the average background temperature. A second field investigation in March 2007 revealed a still-warm PF deposit that contained fumaroles. It was also observed that the upper dome morphology had changed in the past year, with a new lava lobe having in-filled the crater that formed following the 9 May 2006 eruption. These data provide further information on effusive and explosive activity at Bezymianny using quantitative remote sensing data and reinforced by field observations to assist in pre-eruption detection as well as post-eruption monitoring.
Carter A.J., Ramsey M.S., Girina O.A., Belousov A.B., Durant A., Skilling I., Wolfe A. Spaceborne and field-based observations of Bezymianny Volcano, Kamchatka from 2000-2008 // Abstracts. AGU Fall Meeting, 14-19 December. San-Francisco, USA: AGU. 2008. doi: V43A-2140.
Carter Adam J., Ramsey Michael S., Belousov Alexander B. Detection of a new summit crater on Bezymianny Volcano lava dome: satellite and field-based thermal data // Bulletin of Volcanology. 2007. Vol. 69. № 7. P. 811-815. doi:10.1007/s00445-007-0113-x.
Caudron Corentin, Taisne Benoit, Kugaenko Yulia, Saltykov Vadim Magma migration at the onset of the 2012–13 Tolbachik eruption revealed by Seismic Amplitude Ratio Analysis // Journal of Volcanology and Geothermal Research. 2015. Vol. 307. P. 60 - 67. doi: 10.1016/j.jvolgeores.2015.09.010.
Abstract In contrast of the 1975–76 Tolbachik eruption, the 2012–13 Tolbachik eruption was not preceded by any striking change in seismic activity. By processing the Klyuchevskoy volcano group seismic data with the Seismic Amplitude Ratio Analysis (SARA) method, we gain insights into the dynamics of magma movement prior to this important eruption. A clear seismic migration within the seismic swarm, started 20 hours before the reported eruption onset (05:15 UTC, 26 November 2012). This migration proceeded in different phases and ended when eruptive tremor, corresponding to lava flows, was recorded (at ~ 11:00 UTC, 27 November 2012). In order to get a first order approximation of the magma location, we compare the calculated seismic intensity ratios with the theoretical ones. As expected, the observations suggest that the seismicity migrated toward the eruption location. However, we explain the pre-eruptive observed ratios by a vertical migration under the northern slope of Plosky Tolbachik volcano followed by a lateral migration toward the eruptive vents. Another migration is also captured by this technique and coincides with a seismic swarm that started 16–20 km to the south of Plosky Tolbachik at 20:31 {UTC} on November 28 and lasted for more than 2 days. This seismic swarm is very similar to the seismicity preceding the 1975–76 Tolbachik eruption and can be considered as a possible aborted eruption.
Chaplygin Ilya, Yudovskaya Marina, Vergasova Lidiya, Mokhov Andrey Native gold from volcanic gases at Tolbachik 1975–76 and 2012–13 Fissure Eruptions, Kamchatka // Journal of Volcanology and Geothermal Research. 2015. Vol. 307. P. 200 - 209. doi: 10.1016/j.jvolgeores.2015.08.018.
Abstract Aggregates and euhedral crystals of native gold were found in sublimates formed during New Tolbachik Fissure Eruption in 2012–2013 (NTFE). Gold-bearing sublimate samples were taken from a red-hot (690 °C) degassing fracture in the roof of an active lava tunnel 1.5 km from active Naboko cinder cone in May 2013. The gas condensate collected at 690 °C in this site contains 16 ppb Au, 190 ppb Ag and 1180 ppm Cu compared to 3 ppb Au, 39 ppb Ag and 9.7 ppm Cu in the condensate of pristine magmatic gas sampled at 1030 °C. The 690 °C volcanic gas is most likely a mix of magmatic gas and local snow buried under the lava flows as indicated by oxygen and hydrogen isotope compositions of the condensate. The lower-temperature gas enrichment in gold, copper and chlorine is resulted from evaporation of the 690 °C condensate during forced gas pumping at sampling. Native gold was also found in fumarolic encrustations collected from caverns in basalt lava flows with temperature up to 600 °C in June 2014, in a year after eruption finished. The native gold precipitation in newly formed Cu-rich sublimates together with the well known gold occurrences in cinder cones of 1975–1976 Large Tolbachik Fissure Eruption manifest a transport capability of oxidized volcanic gas.
Chapter 1 Recent tectonics of the crust and volcanism in Kamchatka / Quaternary volcanism and tectonics in Kamchatka. Bull. Volcanol.. // Bulletin Volcanologique. 1979. Vol. 42. Vol. 1-4. P. 9-112. doi: 10.1007/BF02597042.
Chapter 2 Basalt and basalt-andesite volcanism in Kamchatka / Quaternary volcanism and tectonics in Kamchatka. Bull. Volcanol.. // Bulletin Volcanologique. 1979. Vol. 42. Vol. 1-4. P. 113-174. doi: 10.1007/BF02597043.
Chapter 3 Acid volcanism in Kamchatka / Quaternary volcanism and tectonics in Kamchatka. Bull. Volcanol.. // Bulletin Volcanologique. 1979. Vol. 42. Vol. 1-4. P. 175-254. doi: 10.1007/BF02597044.
Chubarova O.S., Gorelchik V.I., Garbuzova V.T. Seismic Activity of Bezymyannyi Volcano in 1975-1979 // Volcanology and Seismology. 1983. № 3. P. 303-314.
Churikova T., Dorendorf F., Wörner G. Sources and Fluids in the Mantle Wedge below Kamchatka, Evidence from Across-arc Geochemical Variation // Journal of Petrology. 2001. Vol. 42. № 8. P. 1567-1593. doi:10.1093/petrology/42.8.1567.
Major and trace element and Sr–Nd–Pb isotopic variations in mafic volcanic rocks hve been studied in a 220 km transect across the Kamchatka arc from the Eastern Volcanic Front, over the Central Kamchatka Depression to the Sredinny Ridge in the back-arc. Thirteen volcanoes and lava fields, from 110 to 400 km above the subducted slab, were sampled. This allows us to characterize spatial variations and the relative amount and composition of the slab fluid involved in magma genesis. Typical Kamchatka arc basalts, normalized for fractionation to 6% MgO, display a strong increase in large ion lithophile, light rare earth and high field strength elements from the arc front to the back-arc. Ba/Zr and Ce/Pb ratios, however, are nearly constant across the arc, which suggests a similar fluid input for Ba and Pb. La/Yb and Nb/Zr increase from the arc front to the back-arc. Rocks from the Central Kamchatka Depression range in 87Sr/86Sr from 0·70334 to 0·70366, but have almost constant Nd isotopic compositions (143Nd/144Nd 0·51307–0·51312). This correlates with the highest U/Th ratios in these rocks. Pb-isotopic ratios are mid-ocean ridge basalt (MORB)-like but decrease slightly from the volcanic front to the back-arc. The initial mantle source ranged from N-MORB-like in the volcanic front and Central Kamchatka Depression to more enriched in the back-arc. This enriched component is similar to an ocean-island basalt (OIB) source. Variations in (CaO)6·0–(Na2O)6·0 show that degree of melting decreases from the arc front to the Central Kamchatka Depression and remains constant from there to the Sredinny Ridge. Calculated fluid compositions have a similar trace element pattern across the arc, although minor differences are implied. A model is presented that quantifies the various mantle components (variably depleted N-MORB-mantle and enriched OIB-mantle) and the fluid compositions added to this mantle wedge. The amount of fluid added ranges from 0·7 to 2·1%. The degree of melting changes from ∼20% at the arc front to <10% below the back-arc region. The rocks from volcanoes of the northern part of the Central Kamchatka Depression—to the north of the transect considered in this study—are significantly different in their trace element compositions compared with the other rocks of the transect and their source appears to have been enriched by a component derived from melting of the edge of the ruptured slab.