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Ponomareva Vera A chronology of the Holocene eruptions from the northern Kamchatka volcanoes based on linking major C14-dated tephra sequences with the help of EMPA glass data // Quaternary International. 2012. V. 279–28. P. 383 doi: 10.1016/j.quaint.2012.08.1191.    Аннотация
Volcanic eruptions from Kamchatka have deposited many unique tephra layers over a large region within the North Pacific, providing important isochrons between key sites such as marine ODP core 883 (Pacific Ocean, Detroit Seamount) and Elgygytgyn Lake (Chukotka, eastern Siberia). Here we present a compilation of C14 dates on major Holocene tephras from the volcanically highly active region, based on decades of detailed stratigraphical fieldwork on Shiveluch, Kliuchevskoy, and other volcanoes.The 12-m thick tephra sequence at the Kliuchevskoy slope has been continuously accumulating during the last ∼11 ka. It contains over 200 visible individual tephra layers and no datable organic material. The section is dominated by dark-gray mafic cinders related to Kliuchevskoy activity. In addition, it contains 30 light-colored thin layers of silicic tephra from distant volcanoes including 11 layers from Shiveluch volcano located only 65 km to the north. We have used EMPA glass analysis to correlate most of the marker tephra layers to their source eruptions dated earlier by C14 (Braitseva et al., 1997; Ponomareva et al., 2007), and in this way linked Kliuchevskoy tephra sequence to sequences at other volcanoes including Shiveluch. The C14 dates and tephras from the northern Kamchatka are then combined into a single Bayesian framework taking into account stratigraphical ordering within and between the sites. This approach has allowed us to enhance the reliability and precision of the estimated ages for the eruptions. Age-depth models are constructed to analyse changes in deposition rates and volcanic activity throughout the Holocene. This detailed chronology of the eruptions serves as a basis for understanding temporal patterns in the eruption sequence and geochemical variations of magmas. This research could prove important for the long-term forecast of eruptions and volcanic hazards.
Ponomareva Vera V., Melekestsev Ivan V., Dirksen Oleg V. Sector collapses and large landslides on Late Pleistocene–Holocene volcanoes in Kamchatka, Russia // Journal of Volcanology and Geothermal Research. 2006. V. 158. № 1-2. P. 117-138. doi:10.1016/j.jvolgeores.2006.04.016.    Аннотация
On Kamchatka, detailed geologic and geomorphologic mapping of young volcanic terrains and observations on historical eruptions reveal that landslides of various scales, from small (0.001 km3) to catastrophic (up to 20–30 km3), are widespread. Moreover, these processes are among the most effective and most rapid geomorphic agents. Of 30 recently active Kamchatka volcanoes, at least 18 have experienced sector collapses, some of them repetitively. The largest sector collapses identified so far on Kamchatka volcanoes, with volumes of 20–30 km3 of resulting debris-avalanche deposits, occurred at Shiveluch and Avachinsky volcanoes in the Late Pleistocene. During the last 10,000 yr the most voluminous sector collapses have occurred on extinct Kamen' (4–6 km3) and active Kambalny (5–10 km3) volcanoes. The largest number of repetitive debris avalanches (> 10 during just the Holocene) has occurred at Shiveluch volcano. Landslides from the volcanoes cut by ring-faults of the large collapse calderas were ubiquitous. Large failures have happened on both mafic and silicic volcanoes, mostly related to volcanic activity. Orientation of collapse craters is controlled by local tectonic stress fields rather than regional fault systems.

Specific features of some debris avalanche deposits are toreva blocks — huge almost intact fragments of volcanic edifices involved in the failure; some have been erroneously mapped as individual volcanoes. One of the largest toreva blocks is Mt. Monastyr' — a ∼ 2 km3 piece of Avachinsky Somma involved in a major sector collapse 30–40 ka BP.

Long-term forecast of sector collapses on Kliuchevskoi, Koriaksky, Young Cone of Avachinsky and some other volcanoes highlights the importance of closer studies of their structure and stability.
Ponomareva Vera, Portnyagin Maxim, Derkachev Alexander, Juschus Olaf, Garbe-Schönberg Dieter, Nürnberg Dirk Identification of a widespread Kamchatkan tephra: A middle Pleistocene tie-point between Arctic and Pacific paleoclimatic records // Geophysical Research Letters. 2013. V. 40. № 14. P. 3538-3543. doi:10.1002/grl.50645.    Аннотация
Very few age controls exist for Quaternary deposits over the vast territory of the East Russian Arctic, which hampers dating of major environmental changes in this area and prevents their correlation to climatic changes in the Arctic and Pacific marine domains. We report a newly identified ~177 ka old Rauchua tephra, which has been dispersed over an area of >1,500,000 km2 and directly links terrestrial paleoenvironmental archives from Arctic Siberia with marine cores in the northwest Pacific, thus permitting their synchronization and dating. The Rauchua tephra can help to identify deposits formed in terrestrial and marine environments during the oxygen isotope stage 6.5 warming event. Chemical composition of volcanic glass from the Rauchua tephra points to its island-arc origin, while its spatial distribution singles out the Kamchatka volcanic arc as a source. The Rauchua tephra represents a previously unknown, large (magnitude >6.5) explosive eruption from the Kamchatka volcanic arc.
Ponomareva Vera, Portnyagin Maxim, Derkachev Alexander, Pendea I. Florin, Bourgeois Joanne, Reimer Paula J., Garbe-Schönberg Dieter, Krasheninnikov Stepan, Nürnberg Dirk Early Holocene M~6 explosive eruption from Plosky volcanic massif (Kamchatka) and its tephra as a link between terrestrial and marine paleoenvironmental records // International Journal of Earth Sciences. 2013. V. 102. № 6. P. 1673-1699. doi:10.1007/s00531-013-0898-0.    Аннотация
We report tephrochronological and geochemical data on early Holocene activity from Plosky volcanic massif in the Kliuchevskoi volcanic group, Kamchatka Peninsula. Explosive activity of this volcano lasted for ~1.5 kyr, produced a series of widely dispersed tephra layers, and was followed by profuse low-viscosity lava flows. This eruptive episode started a major reorganization of the volcanic structures in the western part of the Kliuchevskoi volcanic group. An explosive eruption from Plosky (M~6), previously unstudied, produced tephra (coded PL2) of a volume of 10–12 km3 (11–13 Gt), being one of the largest Holocene explosive eruptions in Kamchatka. Characteristic diagnostic features of the PL2 tephra are predominantly vitric sponge-shaped fragments with rare phenocrysts and microlites of plagioclase, olivine and pyroxenes, medium- to high-K basaltic andesitic bulk composition, high-K, high-Al and high-P trachyandesitic glass composition with SiO2 = 57.5–59.5 wt%, K2O = 2.3–2.7 wt%, Al2O3 = 15.8–16.5 wt%, and P2O5 = 0.5–0.7 wt%. Other diagnostic features include a typical subduction-related pattern of incompatible elements, high concentrations of all REE (>10× mantle values), moderate enrichment in LREE (La/Yb ~ 5.3), and non-fractionated mantle-like pattern of LILE. Geochemical fingerprinting of the PL2 tephra with the help of EMP and LA-ICP-MS analyses allowed us to map its occurrence in terrestrial sections across Kamchatka and to identify this layer in Bering Sea sediment cores at a distance of >600 km from the source. New high-precision 14C dates suggest that the PL2 eruption occurred ~10,200 cal BP, which makes it a valuable isochrone for early Holocene climate fluctuations and permits direct links between terrestrial and marine paleoenvironmental records. The terrestrial and marine 14C dates related to the PL2 tephra have allowed us to estimate an early Holocene reservoir age for the western Bering Sea at 1,410 ± 64 14C years. Another important tephra from the early Holocene eruptive episode of Plosky volcano, coded PL1, was dated at 11,650 cal BP. This marker is the oldest geochemically characterized and dated tephra marker layer in Kamchatka to date and is an important local marker for the Younger Dryas—early Holocene transition. One more tephra from Plosky, coded PL3, can be used as a marker northeast of the source at a distance of ~110 km.
Ponomareva Vera, Portnyagin Maxim, Pevzner Maria, Blaauw Maarten, Kyle Philip, Derkachev Alexander Tephra from andesitic Shiveluch volcano, Kamchatka, NW Pacific: chronology of explosive eruptions and geochemical fingerprinting of volcanic glass // International Journal of Earth Sciences. 2015. V. 104. № 5. P. 1459-1482. doi:10.1007/s00531-015-1156-4.    Аннотация
The ~16-ka-long record of explosive eruptions from Shiveluch volcano (Kamchatka, NW Pacific) is refined using geochemical fingerprinting of tephra and radiocarbon ages. Volcanic glass from 77 prominent Holocene tephras and four Late Glacial tephra packages was analyzed by electron microprobe. Eruption ages were estimated using 113 radiocarbon dates for proximal tephra sequence. These radiocarbon dates were combined with 76 dates for regional Kamchatka marker tephra layers into a single Bayesian framework taking into account the stratigraphic ordering within and between the sites. As a result, we report ~1,700 high-quality glass analyses from Late Glacial–Holocene Shiveluch eruptions of known ages. These define the magmatic evolution of the volcano and provide a reference for correlations with distal fall deposits. Shiveluch tephras represent two major types of magmas, which have been feeding the volcano during the Late Glacial–Holocene time: Baidarny basaltic andesites and Young Shiveluch andesites. Baidarny tephras erupted mostly during the Late Glacial time (~16–12.8 ka BP) but persisted into the Holocene as subordinate admixture to the prevailing Young Shiveluch andesitic tephras (~12.7 ka BP–present). Baidarny basaltic andesite tephras have trachyandesite and trachydacite (SiO2 < 71.5 wt%) glasses. The Young Shiveluch andesite tephras have rhyolitic glasses (SiO2 > 71.5 wt%). Strongly calc-alkaline medium-K characteristics of Shiveluch volcanic glasses along with moderate Cl, CaO and low P2O5 contents permit reliable discrimination of Shiveluch tephras from the majority of other large Holocene tephras of Kamchatka. The Young Shiveluch glasses exhibit wave-like variations in SiO2 contents through time that may reflect alternating periods of high and low frequency/volume of magma supply to deep magma reservoirs beneath the volcano. The compositional variability of Shiveluch glass allows geochemical fingerprinting of individual Shiveluch tephra layers which along with age estimates facilitates their use as a dating tool in paleovolcanological, paleoseismological, paleoenvironmental and archeological studies. Electronic tables accompanying this work offer a tool for statistical correlation of unknown tephras with proximal Shiveluch units taking into account sectors of actual tephra dispersal, eruption size and expected age. Several examples illustrate the effectiveness of the new database. The data are used to assign a few previously enigmatic wide-spread tephras to particular Shiveluch eruptions. Our finding of Shiveluch tephras in sediment cores in the Bering Sea at a distance of ~600 km from the source permits re-assessment of the maximum dispersal distances for Shiveluch tephras and provides links between terrestrial and marine paleoenvironmental records.
Portnyagin Maxim, Duggen Svend, Hauff Folkmar, Mironov Nikita, Bindeman Ilya, Thirlwall Matthew, Hoernle Kaj Geochemistry of the late Holocene rocks from the Tolbachik volcanic field, Kamchatka: Quantitative modelling of subduction-related open magmatic systems // Journal of Volcanology and Geothermal Research. 2015. V. 307. P. 133 - 155. doi: 10.1016/j.jvolgeores.2015.08.015.    Аннотация
Abstract We present new major and trace element, high-precision Sr–Nd–Pb (double spike), and O-isotope data for the whole range of rocks from the Holocene Tolbachik volcanic field in the Central Kamchatka Depression (CKD). The Tolbachik rocks range from high-Mg basalts to low-Mg basaltic trachyandesites. The rocks considered in this paper represent mostly Late Holocene eruptions (using tephrochronological dating), including historic ones in 1941, 1975–1976 and 2012–2013. Major compositional features of the Tolbachik volcanic rocks include the prolonged predominance of one erupted magma type, close association of middle-K primitive and high-K evolved rocks, large variations in incompatible element abundances and ratios but narrow range in isotopic composition. We quantify the conditions of the Tolbachik magma origin and evolution and revise previously proposed models. We conclude that all Tolbachik rocks are genetically related by crystal fractionation of medium-K primary magmas with only a small range in trace element and isotope composition. The primary Tolbachik magmas contain ~ 14 wt. of MgO and ~ 4 wt. of {H2O} and originated by partial melting (~ 6) of moderately depleted mantle peridotite with Indian-MORB-type isotopic composition at temperature of ~ 1250 °C and pressure of ~ 2 GPa. The melting of the mantle wedge was triggered by slab-derived hydrous melts formed at ~ 2.8 {GPa} and ~ 725 °C from a mixture of sediments and MORB- and Meiji-type altered oceanic crust. The primary magmas experienced a complex open-system evolution termed Recharge-Evacuation-Fractional Crystallization (REFC). First the original primary magmas underwent open-system crystal fractionation combined with periodic recharge of the magma chamber with more primitive magma, followed by mixing of both magma types, further fractionation and finally eruption. Evolved high-K basalts, which predominate in the Tolbachik field, and basaltic trachyandesites erupted in 2012–2013 approach steady-state {REFC} liquid compositions at different eruption or replenishment rates. Intermediate rocks, including high-K, high-Mg basalts, are formed by mixing of the evolved and primitive magmas. Evolution of Tolbachik magmas is associated with large fractionation between incompatible trace elements (e.g., Rb/Ba, La/Nb, Ba/Th) and is strongly controlled by the relative difference in partitioning between crystal and liquid phases. The Tolbachik volcanic field shows that open-system scenarios provide more plausible and precise descriptions of long-lived arc magmatic systems than simpler, but often geologically unrealistic, closed-system models.
Portnyagin Maxim, Hoernle Kaj, Plechov Pavel Yu., Mironov Nikita, Khubunaya Sergey Constraints on mantle melting and composition and nature of slab components in volcanic arcs from volatiles (H2O, S, Cl, F) and trace elements in melt inclusions from the Kamchatka // Earth and Planetary Science Letters. 2007. V. 255. № 1-2. P. 53-69. doi: 10.1016/j.epsl.2006.12.005.    Аннотация
New and published data on the composition of melt inclusions in olivine (Fo73_yi) from volcanoes of the Kamchatka and northern Kurile Arc are used 1) to evaluate the combined systematics of volatiles (H2O, S, Cl, F) and incompatible trace elements in their parental magmas and mantle sources, 2) to constrain thermal conditions of mantle melting, and 3) to estimate the composition of slab-derived components. We demonstrate that typical Kamchatkan arc-type magmas originate through 5-14% melting of sources similar or slightly more depleted in HFSE (with up to -1 wt.% previous melt extraction) compared to MORB-source mantle, but strongly enriched in H2O,B, Be, Li, Cl. F, LILE, LREE, Th and U. Mean H2O in parental melts f 1.8-2.6 wt.%) decreases with increasing depth to the subducting slab and correlates negatively with both 'fluid-immobile* (e.g. Ti, Na, LREE) and most 'fluid-mobile' (e.g. LILE, S, Cl, F) incompatible elements, implying that solubility in hydrous fluids or amount of water does not directly control the abundance of 'fluid-mobile' incompatible elements. Strong correlation is observed between H2O/Ce and B/Zr (or B/LREE) ratios. Both, calculated H2O in mantle sources (0.1-0.4%) and degrees of melting (5-14%) decrease with increasing depth to the slab indicating that the ultimate source of water in the sub-arc mantle is the subducting oceanic plate and that water flux (together with mantle temperature) governs theextent of mantle melting beneath Kamchatka. A parameterized hydrous melting model [Katzetal. 2003, G3,4(9), 1073] is utilized to estimate that mantle melting beneath Kamchatka occurs at or below the dry peridotite solidus (1245-1330 °C at 1.5-2.0 GPa). Relatively high mantle temperatures (yet lower than beneath back-arc basins and ocean ridges) suggest substantial corner flow driven mantle upwelling beneath Kamchatka in agreement with numerical models implying non-isoviscous mantle wedge rheology. Data from Kamchatka, Mexico and Central America indicate that <5% melting would lake place beneath continental arcs without water flux from the subducting slab. A broad negative correlation appears to exist between crustal thickness and the temperature of magma generation beneath volcanic arcs with larger amounts of decompression melting occurring beneath thinner arc crust (Uihosphere). In agreement with the high mantle temperatures, we observe a systematic change in the composition of slab components with increasing slab depth from solute-poor hydrous fluid beneath the volcanic front to solute-rich hydrous melt or supercritical liquid at deeper depths beneath the rear arc. The solute-rich slab component dominates the budget of LILE, LREE,Th and U in the magmas and originates through wet-melting of subducted sediments and/or altered oceanic crust at > 120 km depth. Melting of the upper parts of subducting plates under water flux from deeper luhosphere (e.g. serpentinites), combined with high .emperatures in the mantie wedge, may be a more common process beneath volcanic arcs than has been previously recognized. 0 2006 Klsevier B.V. All rights reserved.
Portnyagin Maxim, Hoernle Kaj, Plechov Pavel, Mironov Nikita, Khubunaya Sergey Constraints on mantle melting and composition and nature of slab components in volcanic arcs from volatiles (H2O, S, Cl, F) and trace elements in melt inclusions from the Kamchatka Arc // Earth and Planetary Science Letters. 2007. Т. 255. № 1-2. С. 53-69. doi:10.1016/j.epsl.2006.12.005.
Portnyagin Maxim, Ponomareva Vera Kliuchevskoi volcano diary // International Journal of Earth Sciences. 2012. V. 101. № 1. P. 195 doi:10.1007/s00531-011-0710-y.    Аннотация
Numerous ash layers deposited at the slopes of Kliuchevskoi volcano provide a detailed and continuous record of its explosive activity during the last ca. 10,000 years.
Portnyagin Maxim, Ponomareva Vera, Bindeman Ilya, Christel Bogaard, Stepan Krasheninnikov, Olga Bergal-Kuvikas, Nikita Mironov, Anastasia Plechova, Kaj Hoernle Millennium-scale major element variations of Klyuchevskoy volcano magmas (Kamchatka) revealed from high-resolution study of tephra deposits // IAVCEI, Reykjavik. 2008.
Puzankov M.Yu., Bazanova L.I., Maximov A.P., Moskalyova S.V. The initial plinian basic andesite eruptions of the young cone, Avachinsky volcano (Kamchatka) // IV International Biennial Workshop on Subduction Processes emphasizing the Japan-Kurile-Kamchatka-Aleutian Arcs. August 21-27, 2004, Petropavlovsk-Kamchatsky. Petropavlovsk-Kamchatsky: Institute of Volcanology and Seismology FEB RAS. 2004. P. 158-160.
Ramsey Michael, Dehn Jonathan Spaceborne observations of the 2000 Bezymianny, Kamchatka eruption: the integration of high-resolution ASTER data into near real-time monitoring using AVHRR // Journal of Volcanology and Geothermal Research. 2004. V. 135. № 1-2. P. 127-146. doi:10.1016/j.jvolgeores.2003.12.014.    Аннотация
Since its launch in December 1999, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument has been observing over 1300 of the world's volcanoes during the day and night and at different times of the year. At the onset of an eruption, the temporal frequency of these regularly scheduled observations can be increased to as little as 1–3 days at higher latitudes. However, even this repeat time is not sufficient for near real-time monitoring, which is on the order of minutes to hours using poorer spatial resolution (>1 km/pixel) instruments. The eruption of Bezymianny Volcano (Kamchatkan Peninsula, Russia) in March 2000 was detected by the Alaska Volcano Observatory (AVO) and also initiated an increased observation frequency for ASTER. A complete framework of the eruptive cycle from April 2000 to January 2001 was established, with the Advanced Very High Resolution Radiometer (AVHRR) data used to monitor the large eruptions and produce the average yearly background state for the volcano. Twenty, nearly cloud-free ASTER scenes (2 days and 18 nights) show large thermal anomalies covering tens to hundreds of pixels and reveal both the actively erupting and restive (background) state of the volcano. ASTER short-wave infrared (SWIR) and thermal infrared (TIR) data were also used to validate the recovered kinetic temperatures from the larger AVHRR pixels, as well as map the volcanic products and monitor the thermal features on the summit dome and surrounding small pyroclastic flows. These anomalies increase to greater than 90 °C prior to a larger eruption sequence in October 2000. In addition, ASTER has the first multispectral spaceborne TIR capability, which allowed for the modeling of micrometer-scale surface roughness (vesicularity) on the active lava dome. Where coupled with ongoing operational monitoring programs like those at AVO, ASTER data become extremely useful in discrimination of small surface targets in addition to providing enhanced volcanic mapping capabilities.
Rashidov V.A., Romanova I.M., Bondarenko V.I., Palueva A.A. Information technologies in geomagnetic investigations of Late Cenozoic Pacific submarine volcanoes // Russian Journal of Earth Sciences. 2010. V. 11. № 3. P. 1-8. doi:10.2205/2009ES000358.    Аннотация
The original actual materials collected during the geomagnetic research on the research vessel "Vulkanolog" in 1977-1991 (19 volcanological expeditions) resulted in important contribution into the world data on the structure of Late Cenozoic Pacific submarine volcanoes.

The research resulted in a single method analysis of the anomalous magnetic field of submarine volcanoes and volcanic zones within the Kurile, Izu-Bonin, Mariana, Solomon and Kermadec arcs, New Guinean and South China peripheral seas and within the Socorro hot-spot.

It is stressed that the Late Cenozoic submarine volcanoes within the arcs show their presence distinctly in the anomalous magnetic field by local anomalies located within the edifices. Their amplitude may reach 3000 nT, and the horizontal gradient of the field may exceed 100 nT/km. The data interpretation of the hydromagnetic survey allowed distinguishing the internal structure of single submarine volcanoes, volcanic massifs and volcanic zones in various Pacific regions. The authors revealed the bodies forming anomalies within the isolated volcanic edifices and submarine volcanic zones. The 2.5D and 3D modeling resulted in the estimation of the body ages and the period of the submarine volcanic activity.

Besides the research resulted in estimation of the edifice volumes, scale of submarine volcanic activity and drew the conclusion on the evolution of certain volcanic massifs.

In order to classify and visualize the materials on the geomagnetic research we continue to create "Late Cenozoic Pacific submarine volcanoes" information system. Currently the information system includes:

The Internet page "Comparative analysis of the materials on geomagnetic research of various manifestation types of the Late Cenozoic submarine volcanism in the Pacific";
"Late Cenozoic Pacific submarine volcanoes" database;
GIS "Geomagnetic investigations of various appearance types of Late Cenozoic Pacific submarine volcano activity".
The web site http://www.kscnet.ru/ivs/grant/grant_04/index.html contains numerous maps of the anomalous magnetic field, bathymetric and structural maps, fragments of the echo- sounding survey records and continuous acoustic profiling, photos of land volcanoes, references of the Pacific submarine volcanic activity and "Catalogue on the Late Cenozoic Pacific submarine volcanoes" (in Russian).
The database on the Late Cenozoic Pacific submarine volcanoes includes location of submarine volcanoes, magnetic behaviors and chemical composition of dredge rocks and volumes of the volcanic edifices. The database is hosted on the IVS FEB RAS server and is available on the following page: http://www.kscnet.ru/ivs/volcanoes/submarine/.

The GIS contains maps of the anomalous magnetic field and the volcanic edifices relief.

"Late Cenozoic Pacific submarine volcanoes" information system provides researchers with the convenient tools for working with cartographic and attributive data and helps to implement a comprehensive data processing.
Riley Colleen Origin of scatter in paleomagnetic directions of samples from Gorely Volcano, Kamchatka, Russia. Western Washington University: Western Washington University. 1994. Дисс. докт. геол.-мин. наук. 70 p.    Аннотация
Lava flows from sixteen sites at Gorely Volcano, Kamchatka were sampled. Initial analysis showed high within-site scatter for NRM specimen directions. Alternating field and thermal demagnetization of specimens showed single-component magnetization indicating that specimens had not moved or were not exposed to changes in the magnetic field during acquisition of a magnetic direction. Scatter is thought to be either due to movement of the specimen with respect to the magnetic field or change in the magnetic field with respect to the specimen. Four factors were found that would contribute to scatter in specimen directions. These are 1) cooling rate, 2) range of unblocking temperatures, 3) relative time of emplacement, and 4) how the specimen moved or was affected by changes in the magnetic field. Only two sites showed that scatter was due to movement of the specimen. It appears that scatter in other sites resulted from changes in the magnetic field generated from a magma-induced electrical current due to lava flowing in the earth’s magnetic field. These changes in the magnetic field are shown to have more affect on material sampled at the surface than on material sampled at depth because massive interiors of flows showed less dispersion in specimen directions than levees or pull-aparts.
Romanova I.M., Girina O.A., Maximov A.P., Melekestsev I.V., Vasiliev S.E. Volcanoes of Kurile-Kamchatka Islands Arc Information System for Integration Heterogeneous Volcanological Data // Abstracts. International Workshop “JKASP-8”. Sapporo. Japan. September 22-26. 2014. 2014.
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.
Romanova Iraida M. IVS FEB RAS Geoportal for integration and increasing availability of volcanological data // IAVCEI 2013 Scientific Assembly. July 20 - 24, Kagoshima, Japan. 2013. P. 1279
Romanova Iraida M., Girina O.A., Maximov Alexander P., Melekestsev Ivan V. Volcanoes of Kurile-Kamchatka Islands Arc information system // IAVCEI 2013 Scientific Assembly. July 20 - 24, Kagoshima, Japan. 2013. P. 1278
Rowell Colin R., Fee David, Szuberla Curt A.L., Arnoult Ken, Matoza Robin S., Firstov Pavel P., Kim Keehoon, Makhmudov Evgeniy Three-dimensional volcano-acoustic source localization at Karymsky Volcano, Kamchatka, Russia // Journal of Volcanology and Geothermal Research. 2014. V. 283. P. 101 - 115. doi: 10.1016/j.jvolgeores.2014.06.015.    Аннотация
Abstract We test two methods of 3-D acoustic source localization on volcanic explosions and small-scale jetting events at Karymsky Volcano, Kamchatka, Russia. Recent infrasound studies have provided evidence that volcanic jets produce low-frequency aerodynamic sound (jet noise) similar to that from man-made jet engines. For man-made jet noise, noise sources localize along the turbulent jet flow downstream of the nozzle. Discrimination of jet noise sources along the axis of a volcanic jet requires high resolution in the vertical dimension, which is very difficult to achieve with typical volcano-acoustic network geometries. At Karymsky Volcano, an eroded edifice (Dvor Caldera) adjacent to the active cone provided a platform for the deployment of five infrasound sensors in July 2012 with intra-network relief of ~ 600 m. The network was designed to target large-scale jetting, but unfortunately only small-scale jetting and explosions were recorded during the 12-day experiment. A novel 3-D inverse localization method, srcLoc, is tested and compared against a more common grid-search semblance technique. Simulations using synthetic signals show that srcLoc is capable of determining vertical solutions to within ± 150 m or better (for signal-to-noise ratios ≥ 1) for this network configuration. However, srcLoc locations for explosions and small-scale jetting at Karymsky Volcano show a persistent overestimation of source elevation and underestimation of sound speed. The semblance method provides more realistic source locations, likely because it uses a fixed, realistic sound speed of ~ 340 m/s. Explosion waveforms exhibit amplitude relationships and waveform distortion strikingly similar to those theorized by modeling studies of wave diffraction around the crater rim. We suggest that the delay of acoustic signals and apparent elevated source locations are due to raypaths altered by topography and/or crater diffraction effects, implying that topography in the vent region must be accounted for when attempting 3-D volcano acoustic source localization. Though the data presented here are insufficient to resolve small-scale jet noise sources, similar techniques may be successfully applied to large volcanic jets in the future.
Senyukov S.L., Nuzhdina I.N., Droznina S.Ya., Garbuzova V.T., Kozhevnikova T.Yu., Sobolevskaya O.V., Nazarova Z.A., Bliznetsov V.E. Reprint of "Seismic monitoring of the Plosky Tolbachik eruption in 2012-2013 (Kamchatka Peninsula Russia)" // Journal of Volcanology and Geothermal Research. 2015. V. 307. P. 47 - 59. doi: 10.1016/j.jvolgeores.2015.07.026.    Аннотация
Abstract The active basaltic volcano Plosky Tolbachik (Pl. Tolbachik) is located in the southern part of the Klyuchevskoy volcano group on the Kamchatka Peninsula. The previous 1975–1976 Great Tolbachik Fissure Eruption (1975–1976 GTFE) occurred in the southern sector of Pl. Tolbachik. It was preceded by powerful earthquakes with local magnitudes between 2.5 and 4.9 and it was successfully predicted with a short-term forecast. The Kamchatka Branch of Geophysical Survey (KBGS) of the Russian Academy of Science (RAS) began to publish the results of daily seismic monitoring of active Kamchatka volcanoes on the Internet in 2000. Unlike the 1975–1976 {GTFE} precursor, (1) seismicity before the 2012–2013 Tolbachik Fissure Eruption (2012–2013 TFE) was relatively weak and earthquake magnitudes did not exceed 2.5. (2) Precursory earthquake hypocenters at 0–5 km depth were concentrated mainly under the southeastern part of the volcano. (3) The frequency of events gradually increased in September 2012, and rose sharply on the eve of the eruption. (4) According to seismic data, the explosive-effusive 2012–2013 {TFE} began at ~ 05 h 15 min {UTC} on November 27, 2012; the outbreak occurred between the summit of the Pl. Tolbachik and the Northern Breakthrough of the 1975–1976 GTFE. (5) Because of bad weather, early interpretations of the onset time and the character of the eruption were made using seismological data only and were confirmed later by other monitoring methods. The eruption finished in early September 2013. This article presents the data obtained through real-time seismic monitoring and the results of retrospective analysis, with additional comments on the future monitoring of volcanic activity.


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