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Records: 2603
Tokarev P.I. The March - June 1984 Eruption of Klyuchevskoi and its Present State as Estimated from Original Observations // Volcanology and Seismology. 1988. Vol. 7. № 1. P. 143-148.
Tokarev P.I. Volcanic Explosions. On the concept of "Volcanic Explosion" // Volcanology and Seismology. 1983. № 3. P. 315-322.
Tolstikhin I.N., Mamyrin B.A., Khabarin L.B., Erlikh E.N. Isotope composition of helium in ultrabasic xenoliths from volcanic rocks of Kamchatka // Earth and Planetary Science Letters. 1974. Vol. 22. № 1. P. 75-84.
The purpose of this work is to refine our knowledge about the nature of helium with a high abundance of the rare isotope3He(3He/4He= 10−5) discovered in terrestrial volcanic gases in 1968.
We will discuss here the results of isotope analyses of helium released by step-wise heating of ultrabasic xenoliths and some volcanic rocks. On the basis of these results, possible sources of3He in the earth due to fission and nuclear reactions are considered critically. The most probable source of the high abundance of3He is shown to be due to the capture and trapping of primordial He by the earth during its formation (primordial helium3He/4He= 3 × 10−4), a small but significant fraction of which has been retained to the present time.
Tolstykh M.L., Naumov V.B., Gavrilenko M.G., Ozerov A.Yu., Kononkova N.N. Chemical composition, volatile components, and trace elements in the melts of the Gorely volcanic center, southern Kamchatka: Evidence from inclusions in minerals // Geochemistry International. 2012. Vol. 50. № 6. P. 522-550. doi:10.1134/S0016702912060079.
Tolstykh M.L., Naumov V.B., Ozerov A.Yu., Kononkova N.N. Composition of Magmas of the 1996 Eruption at the Karymskii Volcanic Center, Kamchatka: Evidence from Melt Inclusions // Geochemistry International. 2001. Vol. 39. № 5. P. 447-458.
Torsvik T., Paris R., Didenkulova I., Pelinovsky E., Belousov A., Belousova M. Numerical simulation of a tsunami event during the 1996 volcanic eruption in Karymskoye lake, Kamchatka, Russia // Natural Hazards and Earth System Science. 2010. Vol. 10. № 11. P. 2359-2369. doi:10.5194/nhess-10-2359-2010.
Trifonov Grigory, Zhizhin Mikhail, Melnikov Dmitry, Poyda Alexey VIIRS Nightfire Remote Sensing Volcanoes // Procedia Computer Science. 2017. Vol. 119. P. 307-314. doi: 10.1016/j.procs.2017.11.189.
Satellite based remote sensing of active volcanoes has been performed in various forms since 1965. Compared to “on the ground” observations it lets data to be gathered globally at regular pace for long periods of time without the need for local maintenance. Currently existing publicly available volcanoes thermal activity monitoring systems rely on the detection algorithms narrowly specified for volcanoes temperature ranges and operate using the data from previous generation of sensors, which is supported with non-reserved constellation of two satellites. The presented work proposes pipeline (the sequence of actions) based on the clustering of the data received from the Nightfire thermal anomalies detection algorithm, which is not focused on the specific type of infrared sources. Pipeline has been tested on Kamchatka’s region 2016 year dataset and proved to produce sound results corresponding to manual observations.
Turner S.P., Sims K.W.W., Reagan M.K. A 210Pb–226Ra–230Th–238U study of Klyuchevskoy and Bezymianny volcanoes, Kamchatka // Geochimica et Cosmochimica Acta. 2006. Vol. 70. № 18, Su. P. A661 doi: 10.1016/j.gca.2006.06.1234.
Klyuchevskoy is one of the most active volcanoes on Earth, erupting lavas at a rate of ∼1 m3/s, equivalent to a 50 km length of mid-ocean ridge. Bezymianny is located 20 km south of the summit vent of Klyuchevskoy and has been erupting silicic andesites since its spectacular avalanche eruption in 1956. Major and trace element concentrations and long-lived radiogenic isotope data suggest that basalts and basaltic andesites from Klyuchevskoy and andesites from Bezymianny were derived by different degrees of partial melting of nearly identical mantle sources. Lavas with higher SiO2 concentrations represent the differentiation products of lower degrees of melting after the mantle was fluxed with a fluid derived almost entirely from subducted altered basaltic crust with little or no sediment contribution. The higher SiO2 concentrations for lavas derived from smaller degree melts suggest that they underwent more fractionation because of the loss of their higher water contents. High Th isotope compositions for all lavas from both volcanoes suggest that a significant time transpired between U addition by a slab-fluid and melting. If the excess 226Ra in the lavas is from the slab-fluid, then long term multistage fluxing before melting is required to maintain these 226Ra excesses. An alternative model attributes the excess Ra to melting caused by upwelling mantle in association with rifting of the central Kamchatka depression. The greater Ra excess for Klyuchevskoi’s basaltic andesites compared to its basalts is consistent with generation of the Ra excesses during decompression melting, and a less than few thousand year time frame of differentiation after melting. The lower Ra excesses for Bezymianny’s andesites compared to the more mafic lavas suggest a time frame of fractionation that is longer than this by several thousand years. When time since eruption is accounted for, all samples have (210Pb/226Ra) within 2σ analytical error of one, suggesting that significant long-term gas fluxing of 222Rn into or out of both magma systems has not occurred.
Turner Simon, Sims Kenneth W.W., Reagan Mark, Cook Craig A 210Pb–226Ra–230Th–238U study of Klyuchevskoy and Bezymianny volcanoes, Kamchatka // Geochimica et Cosmochimica Acta. 2007. Vol. 71. № 19. P. 4771 - 4785. doi: 10.1016/j.gca.2007.08.006.
Lavas from Klyuchevskoy and Bezymianny volcanoes, Kamchatka, appear to show a link between the extent of partial melting in their mantle source region and the subsequent degree of fractionation suffered by the magmas during passage through the crust. This fractionation may have occurred on timescales significantly less than 1000 years if observed 226Ra excesses largely reflect variable residual porosity in the source melting region. Unlike most arc lavas, those with the highest MgO contents and Ba/Th ratios have the lowest 226Ra excess. Forward models suggest that those portions of the source which had undergone the greatest addition of U by fluids from the subducting plate also underwent the greatest extents of partial melting at the highest residual porosity. At Kluchevskoy, a change from eruption of high-MgO to high-Al2O3 basaltic andesites around 1945 is reflected in an increase in size of 226Ra excess which seems to require a simultaneous decrease in residual porosity and suggests a rapid changes in the melting regime. The eruption of andesites at Bezyminanny, simultaneous with the eruption of basaltic andesites at Klyuchevskoy, further suggests that different degree melts produced at differing residual porosity can be formed and extracted from the melt region at the same time. Thus, the melting processes beneath Klyuchevskoy and Bezyminanny are demonstrably complex. They have clearly been influenced by both fluid addition from the subducting plate and extension and decompression beneath the Central Kamchatka Depression. Finally, the 210Pb data are, with one or two exceptions, in equilibrium with 226Ra, suggesting that there was restricted relative magma-gas movement in this highly productive magmatic system.
VONA/KVERT Information Releases. 2005.