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Статьи
Taran Yu.A., Pilipenko V.P., Rozhkov A.M., Vakin E.A. A geochemical model for fumaroles of the Mutnovsky volcano, Kamchatka, USSR // Journal of Volcanology and Geothermal Research. 1992. V. 49. № 3–4. P. 269 - 283. doi: 10.1016/0377-0273(92)90018-9.    Аннотация
On the basis of the chemical, isotopic and thermodynamic characteristics of fluids sampled between 1964 and 1989 a genetic model description is given for fumaroles of the Mutnovsky volcano. There are three individual groups of fumaroles in the Mutnovsky crater which show stable activity for a long period of time: “the Active Funnel” (temperatures exceed 600°C), the “Upper Field” (up to 320°C) and the “Bottom Field” (from 100 to 150°C). The three principal zones of emission have different gas composition, water isotopic composition, radioactivity and 3He/4He ratios. The abundance of magmatic components in the high-temperature fumaroles of the “Active Funnel” is much higher than those in gases from the other groups. Emission rate of SO2 from the “Active Funnel” is about 200 t/d, which requires complete degassing as a minimum of 1 km3 of magma every 20 years. Fluids of the “Upper Field” contain up to 80% of steam from the Mutnovsky geothermal system. Temperature variations of the “Bottom Field” fumaroles (from 97°C before 1982 to 151°C in 1989) result from changes in hydrological conditions in the crater. Evaporation of high-saline acid brine which is formed in the interior of the volcano is responsible for the composition of the “Bottom Field” gas-steam discharges.
Taran Yu.A., Rozhkov A.M., Serafimova E.K., Esikov A.D. Chemical and isotopic composition of magmatic gases from the 1988 eruption of Klyuchevskoy volcano, Kamchatka // Journal of Volcanology and Geothermal Research. 1991. V. 46. № 3–4. P. 255 - 263. doi: 10.1016/0377-0273(91)90087-G.    Аннотация
Gas samples have been collected at the place of magma effusion during the 1988 flank eruption of Klyuchevskoy, for the first time in the course of studies at this volcano. The high-temperature gases (1000–1100°C) are rich in water and halogens but depleted in sulphur. Their molar composition is close to chemical equilibrium at the collection temperature, while their oxidation state corresponds to redox conditions between FMO and NNO buffers. The isotopic composition of the water (δD = −71 to −44‰; δ18O = +6.3 to +8.4‰, versus SMOW) plots within the field of “primary magmatic” waters. The isotopic composition of H2 (δD = −187‰ to −160‰) is consistent with isotopic equilibrium between H2 and H2O in the conditions of emission. Both the chemistry of the gases and the low δ13C of carbon dioxide (−11.6‰, PDB) suggest extensive magma outgassing occurred during the course of the eruption.
Taran Yuri, Inguaggiato Salvatore, Cardellini Carlo, Karpov Gennady Posteruption chemical evolution of a volcanic caldera lake: Karymsky Lake, Kamchatka // Geophysical Research Letters. 2013. V. 40. № 19. P. 5142-5146. doi:10.1002/grl.50961.    Аннотация
The 1996 short-lived subaqueous eruption at the Karymsky caldera lake suddenly changed the composition of the lake water. The lake, with a surface area of ∼10 km^2 and a volume of ∼0.5 km^3, became acidic, increased its salinity to ∼1000 mg/kg, and became dominated by SO4^2- and Ca^2+. Since the eruption, the lake chemistry has evolved in a predictable manner described by simple box model. As a result of dilution by incoming SO4-Ca-Mg-poor water, SO4, Ca, and Mg concentrations follow a simple exponential decrease with a characteristic time close to the residence time of the lake. Na, K, and Cl decrease relatively significantly slower, indicating a continuing input of these constituents into the lake that was initiated during the eruption. Thus, the dynamics of two groups of lake water solutes can be predicted by a simple box model for water and solute mass balance. Key Points Karymsky lake suddenly changed chemistry as a result of the 1996 eruption One-box dynamic model correctly describes the evolution of the lake chemistry The calculated fluxes of chemicals are in a good agreement with the field data
Telling J., Flower V.J.B., Carn S.A. A multi-sensor satellite assessment of SO2 emissions from the 2012–13 eruption of Plosky Tolbachik volcano, Kamchatka // Journal of Volcanology and Geothermal Research. 2015. V. 307. P. 98 - 106. doi: 10.1016/j.jvolgeores.2015.07.010.    Аннотация
Abstract Prolonged basaltic effusive eruptions at high latitudes can have significant atmospheric and environmental impacts, but can be challenging to observe in winter conditions. Here, we use multi-sensor satellite data to assess sulfur dioxide (SO2) emissions from the 2012–2013 eruption of Plosky Tolbachik volcano (Kamchatka), which lasted ~ 9–10 months and erupted ~ 0.55 km3 DRE. Observations from the Ozone Monitoring Instrument (OMI), the Ozone Mapping and Profiler Suite (OMPS), the Atmospheric Infrared Sounder (AIRS), and the Moderate Resolution Imaging Spectroradiometer (MODIS) are used to evaluate volcanic activity, SO2 emissions and heat flux associated with the effusion of lava flows. Gaps in the primary OMI SO2 time-series dataset occurred due to instrument limitations and adverse meteorological conditions. Four methods were tested to assess how efficiently they could fill these data gaps and improve estimates of total SO2 emissions. When available, using data from other {SO2} observing instruments was the most comprehensive way to address these data gaps. Satellite measurements yield a total SO2 loading of ~ 200 kt SO2 during the 10-month Plosky Tolbachik eruption, although actual SO2 emissions may have been greater. Based on the satellite SO2 measurements, the Fast Fourier Transform (FFT) multi-taper method (MTM) was used to analyze cyclical behavior in the complete data series and a 55-day cycle potentially attributable to the eruptive behavior of Plosky Tolbachik during the 2012 – 2013 eruption was identified.
Tibaldi Alessandro, Corazzato Claudia, Kozhurin Andrey, Lagmay Alfredo F.M., Pasquarè Federico A., Ponomareva Vera V., Rust Derek, Tormey Daniel, Vezzoli Luigina Influence of substrate tectonic heritage on the evolution of composite volcanoes: Predicting sites of flank eruption, lateral collapse, and erosion // Global and Planetary Change. 2008. V. 61. № 3-4. P. 151-174. doi:10.1016/j.gloplacha.2007.08.014.    Аннотация
This paper aims to aid understanding of the complicated interplay between construction and destruction of volcanoes, with an emphasis on the role of substrate tectonic heritage in controlling magma conduit geometry, lateral collapse, landslides, and preferential erosion pathways. The influence of basement structure on the development of six composite volcanoes located in different geodynamic/geological environments is described: Stromboli (Italy), in an island arc extensional tectonic setting, Ollagüe (Bolivia–Chile) in a cordilleran extensional setting, Kizimen (Russia) in a transtensional setting, Pinatubo (Philippines) in a transcurrent setting, Planchon (Chile) in a compressional cordilleran setting, and Mt. Etna (Italy) in a complex tectonic boundary setting. Analogue and numerical modelling results are used to enhance understanding of processes exemplified by these volcanic centres. We provide a comprehensive overview of this topic by considering a great deal of relevant, recently published studies and combine these with the presentation of new results, in order to contribute to the discussion on substrate tectonics and its control on volcano evolution. The results show that magma conduits in volcanic rift zones can be geometrically controlled by the regional tectonic stress field. Rift zones produce a lateral magma push that controls the direction of lateral collapse and can also trigger collapse. Once lateral collapse occurs, the resulting debuttressing produces a reorganization of the shallow-level magma migration pathways towards the collapse depression. Subsequent landslides and erosion tend to localize along rift zones. If a zone of weakness underlies a volcano, long-term creep can occur, deforming a large sector of the cone. This deformation can trigger landslides that propagate along the destabilized flank axis. In the absence of a rift zone, normal and transcurrent faults propagating from the substrate through the volcano can induce flank instability in directions respectively perpendicular and oblique to fault strike. This destabilization can evolve to lateral collapse with triggering mechanisms such as seismic activity or magmatic intrusion.
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. V. 50. № 6. P. 522-550. doi:10.1134/S0016702912060079.
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. V. 10. № 11. P. 2359-2369. doi:10.5194/nhess-10-2359-2010.
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. V. 70. № 18, Su. P. A661 doi: 10.1016/j.gca.2006.06.1234.    Аннотация
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. V. 71. № 19. P. 4771 - 4785. doi: 10.1016/j.gca.2007.08.006.    Аннотация
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.
Viccaro Marco, Giuffrida Marisa, Nicotra Eugenio, Ozerov Alexey Yu. Magma storage, ascent and recharge history prior to the 1991 eruption at Avachinsky Volcano, Kamchatka, Russia: Inferences on the plumbing system geometry // Lithos. 2012. V. 140–14. P. 11 - 24. doi: 10.1016/j.lithos.2012.01.019.    Аннотация
Textural and compositional features of plagioclase phenocrysts of the 1991 eruption lavas at Avachinsky Volcano (Kamchatka, Russia) were used to investigate the feeding system processes. Volcanics are porphyritic basaltic andesites and andesites with low-K affinity. A fractionation modeling for both major and trace elements was performed to justify the development of these evolved compositions. The occurrence of other magma chamber processes was verified through high-contrast BSE images and core-to-rim compositional profiles (An and FeO wt.) on plagioclase crystals. Textural types include small and large-scale oscillation patterns, disequilibrium textures at the crystal core (patchy zoning, coarse sieve-textures, dissolved cores), disequilibrium textures at the crystal rim (sieve-textures), melt inclusion alignments at the rim. Disequilibrium textures at the cores may testify episodes of destabilization at various decompression rates under water-undersaturated conditions, which suggests different pathways of magma ascent at depth. At shallower, water-saturated conditions, plagioclase crystallization continues in a system not affected by important chemical-physical perturbations (oscillatory zoning develops). Strongly sieve-textured rims, along with An increase at rather constant FeO, are evidence of mixing before the 1991 eruption between a residing magma and a hotter and volatile-richer one. The textural evidence implies that crystals underwent common histories at shallow levels, supporting the existence of a large magma reservoir whose top is at ~ 5.5 km of depth. Distinct textures at the outer rims in a hand-size sample are evidence that crystals mix mechanically at very shallow levels, probably in a small reservoir at ~ 1.8 km of depth.
Vikulin A.V., Akmanova D.R., Vikulina S.A., Dolgaya A.A. Migration of seismic and volcanic activity as display of wave geodynamic process // Geodynamics & Tectonophysics. 2012. V. 3. № 1. P. 1-18. doi: 10.5800/GT-2012-3-1-0058.    Аннотация
Publications about the earthquake foci migration have been reviewed. An important result of such studies is establishment of wave nature of seismic activity migration that is manifested by two types of rotational waves; such waves are responsible for interaction between earthquakes foci and propagate with different velocities. Waves determining long-range interaction of earthquake foci are classified as Type 1; their limiting velocities range from 1 to 10 cm/s. Waves determining short-range interaction of foreshocks and aftershocks of individual earthquakes are classified as Type 2; their velocities range from 1 to 10 km/s. According to the classification described in [Bykov, 2005], these two types of migration waves correspond to slow and fast tectonic waves.
The most complete data on earthquakes (for a period over 4.1 million of years) and volcanic eruptions (for 12 thousand years) of the planet are consolidated in a unified systematic format and analyzed by methods developed by the authors. For the Pacific margin, Alpine-Himalayan belt and the Mid-Atlantic Ridge, which are the three most active zones of the Earth, new patterns of spatial and temporal distribution of seismic and volcanic activity are revealed; they correspond to Type 1 of rotational waves. The wave nature of the migration of seismic and volcanic activity is confirmed. A new approach to solving problems of geodynamics is proposed with application of the data on migration of seismic and volcanic activity, which are consolidated in this study, in combination with data on velocities of movement of tectonic plate boundaries. This approach is based on the concept of integration of seismic, volcanic and tectonic processes that develop in the block geomedium and interact with each other through rotating waves with a symmetric stress tensor. The data obtained in this study give grounds to suggest that a geodynamic value, that is mechanically analogous to an impulse, remains constant in such interactions. It is thus shown that the process of wave migration of geodynamic activity should be described by models with strongly nonlinear equations of motion.

Проведен обзор работ по миграции очагов землетрясений. Важным результатом явилось установление волновой природы миграции сейсмической активности, которая осуществляется двумя типами ротационных волн, ответственными за взаимодействие очагов землетрясений и распространяющимися с разными скоростями. Первому типу с предельными скоростями 1–10 см/с соответствуют волны, определяющие дальнодействующее взаимодействие очагов землетрясений, второму – с предельными скоростями 1–10 км/с – соответствуют волны, определяющие близкодействующее взаимодействие форшоков и афтершоков в пределах отдельно взятых очагов землетрясений. Согласно классификации [Bykov, 2005], такие типы волн миграции соответствуют медленным и быстрым тектоническим волнам.
В едином формате представлены наиболее полные данные о землетрясениях за 4.1 тыс. лет и извержениях вулканов за 12 тыс. лет. Собранные данные систематизированы и проанализированы с помощью разработанных авторами методик. Для трех наиболее активных поясов Земли – Пацифики, Альпийско-Гималайского и Срединно-Атлантического – установлены новые, отвечающие первому типу ротационных волн, закономерности пространственно-временного распределения сейсмической и вулканической активности. Подтверждена волновая природа их миграции. Полученные в работе данные в совокупности с данными о скоростях движения границ тектонических плит предлагается использовать в качестве нового подхода к решению задач геодинамики. В основе такого подхода заложена идея единства сейсмического, вулканического и тектонического процессов, протекающих в блоковой геосреде и взаимодействующих между собой посредством ротационных волн с симметричным тензором напряжений. Полученные авторами данные позволяют предположить, что при таком взаимодействии сохраняется геодинамическая величина, механическим аналогом которой является импульс. Показано, что процесс волновой миграции геодинамической активности должен описываться в рамках моделей с сильно нелинейными уравнениями движения.
Vikulin A.V., Akmanova D.R., Vikulina S.A., Dolgaya A.A. Migration of seismic and volcanic activity as display of wave geodynamic process // New Concepts in Global Tectonics Newsletter. 2012. № 64. P. 94-110.    Аннотация
Publications about the earthquake foci migration have been reviewed. An important result of such studies is establishment of wave nature of seismic activity migration that is manifested by two types of rotational waves; such waves are responsible for interaction between earthquakes foci and propagate with different velocities. Waves determining long-range interaction of earthquake foci are classified as Type 1; their limiting velocities range from 1 to 10 cm/s. Waves determining short-range interaction of foreshocks and aftershocks of individual earthquakes are classified as Type 2; their velocities range from 1 to 10 km/s. According to the classification described in [Bykov, 2005], these two types of migration waves correspond to slow and fast tectonic waves. The most complete data on earthquakes (for a period over 4.1 million of years) and volcanic eruptions (for 12 thousand years) of the planet are consolidated in a unified systematic format and analyzed by methods developed by the authors. For the Pacific margin, Alpine-Himalayan belt and the Mid-Atlantic Ridge, which are the three most active zones of the Earth, new patterns of spatial and temporal distribution of seismic and volcanic activity are revealed; they correspond to Type 1 of rotational waves. The wave nature of the migration of seismic and volcanic activity is confirmed. A new approach to solving problems of geodynamics is proposed with application of the data on migration of seismic and volcanic activity, which are consolidated in this study, in combination with data on velocities of movement of tectonic plate boundaries. This approach is based on the concept of integration of seismic, volcanic and tectonic processes that develop in the block geomedium and interact with each other through rotating waves with a symmetric stress tensor. The data obtained in this study give grounds to suggest that a geodynamic value, that is mechanically analogous to an impulse, remains constant in such interactions. It is thus shown that the process of wave migration of geodynamic activity should be described by models with strongly nonlinear equations of motion.
Vinogradov V.N., Muravyev Y.D., Nikitina I.M., Salamatin A.N. Production of phreatic explosions in the interaction of lava and ice // Volcanology and Seismology. 1990. V. 9. № 1. P. 89-98.    Аннотация
A matematical model is given of the formation of phreatic explosions in lava flows coming into contact with ice formations. Quantitative characteristics are derived for the various stages in the development of the explosion; by means of wich its strength and other parameters may be evaluated. The theoretical calculation results are in agreement with empirical data.
Vlodavetz V.I., Naboko S.I., Piip B.I. Relations between the of eruptions and the composition of lava as exemplified by Kamchatka and Kuriles Volcanoes // Bulletin of Volcanology. 1963. № 26. P. 100-111.
Vlodavetz V.I., Naboko S.I., Piip B.I. Relations between the type of eruptions and the composition of lava as exemplified by Kamchatka and Kuriles Volcanoes // Bulletin of Volcanology. 1963. V. 26. № 1. P. 100-111. doi: 10.1007/BF02597279.
Voight B., Komorowski J-C., Norton G. E., Belousov A. B., Belousova M., Boudon G., Francis P. W., Franz W., Heinrich P., Sparks R. S. J., Young S. R. The 26 December (Boxing Day) 1997 sector collapse and debris avalanche at Soufriere Hills Volcano, Montserrat // Geological Society, London, Memoirs. 2002. V. 21. № 1. P. 363-407. doi:10.1144/GSL.MEM.2002.021.01.17.
Volynets A.O., Melnikov D.V., Yakushev A.I. First data on composition of the volcanic rocks of the IVS 50th anniversary Fissure Tolbachik eruption (Kamchatka) // Doklady Earth Sciences. 2013. V. 452. № 1. P. 953-957. doi:10.1134/S1028334X13090201.    Аннотация
First data on major, minor and trace element (XRF. ICP-MS) concentrations in the volcanic rocks of the IVS 50th anniversary Fissure Tolbachik eruption are reported for the period from 27.11.2012 to 25.01.2013; scheme of lava flows distribution by March 2013 is made. The volcanic rocks of the new eruption are substantially different from the other studied volcanic rocks of Tolbachinsky Dol by their higher alkalis and incompatible elements content. The rocks of the first three days of eruption (Menyailov Vent) have higher silica and alkalis content than all previously reported volcanic rocks of Tolbachinsky Dol. Volcanic rocks of the Naboko Vent, at silica content similar to high-Al basalts of Tolbachinsky Dol, have different concentrations of trace elements and some major elements (K2O, CaO, TiO2, P2O5). REE and other incompatible element concentrations in the rocks of the Menyailov Vent are higher than in the rocks of the Naboko Vent at the same element ratios. The differences of the volcanic rocks of the two vents of the new eruption may be caused by the fact that the erupted lavas came from the different levels of the same magma chamber.
http://repo.kscnet.ru/1103/ [связанный ресурс]
Volynets Anna O., Edwards Benjamin R., Melnikov Dmitry, Yakushev Anton, Griboedova Irina Monitoring of the volcanic rock compositions during the 2012–2013 fissure eruption at Tolbachik volcano, Kamchatka // Journal of Volcanology and Geothermal Research. 2015. V. 307. P. 120 - 132. doi: 10.1016/j.jvolgeores.2015.07.014.    Аннотация
Abstract Here we present the results from monitoring of the composition of rocks produced during the 2012–2013 fissure eruption at Tolbachik volcano (FTE). Major and trace element concentrations in 75 samples are reported. Products of this eruption are represented by high alumina basaltic trachyandesites with higher alkalis and titanium contents than in all previously studied rocks of the Tolbachik monogenetic volcanic field. Rocks erupted during the first three days (27–30 November) from the northern (also called Menyailov) group of vents are the most silica- and alkali-rich (SiO2 concentrations up to 55.35 wt. and {K2O} up to 2.67 wt.). From December onwards, when the eruptive activity switched from the Menyailov vents to the southern (Naboko) group of vents, silica content dropped by 2 wt., concentrations of MgO, FeO, TiO2 and Mg# increased, and {K2O} and Na2O concentrations and K2O/MgO ratio decreased. For the rest of the eruption the compositions of rocks remained constant and homogeneous; no systematic compositional differences between lava, bombs and scoria samples are evident. Trace element distributions in the rocks of the Menyailov and Naboko vent lavas are relatively uniform; Menyailov lavas have slightly higher Th, Nb, Hf, Y, and {HREE} concentrations than the Naboko vent lavas at more or less constant element ratios. We explain the initial change in geochemistry by tapping of a slightly cooler and fractionated (~ 3 Mt and 8 Cpx) upper part of the magma storage zone before the main storage area began to feed the eruption. Thermodynamic constraints show that apparent liquidus temperatures varied from 1142 °C to 1151 °C, and thermodynamic modeling shows that variations in compositions are consistent with a high degree of low pressure (100–300 MPa), nominally anhydrous fractionation of a parent melt compositionally similar to the 1975 Northern Breakthrough high-Mg basalt. Geochemistry, petrological observations and modeling are in agreement with the newly erupted material being derived from remnant high-Al magma from the 1975–76 Southern Breakthrough eruption with only slight amounts of cooling (less than 1 °C per year) during the intervening 36 years.
Volynets O.N., Melekestsev I.V., Ponomareva V.V., Yogodzinski G.M. Kharchinsky and Zarechnyi volcanoes - unique centers of late Pleistocene magnesian basalts in Kamchatka: Structural setting, morphology, geologic structure and age // Volcanology and Seismology. 1999. V. 20. № 4-5. P. 383-399.    Аннотация
This paper presents the results of studying the spatial distribution and structural setting of magnesian basalts and andesites in the Northern group of Kamchatkan volcanoes and in the junction zone of the Kuril-Kamchatka and Aleutian island arcs. The morphology and geologic structure of unique Kamchatkan magnesian basalt stratovolcanoes are described: Kharchinsky, Zarechnyi, and the Kharchinsky regional zone of cinder cones. The reported evidence includes the ages and eruptive histories, and productivities of the volcanoes and the volumes and weights of their edifices. The magnesian basalts were erupted 40-50 thousand years ago, for the first time during the Holocene.
http://repo.kscnet.ru/842/ [связанный ресурс]
Volynets O.N., Melekestsev I.V., Ponomareva V.V., Yogodzinski J.M. Kharchinskii and Zarechnyi volcanoes, unique centers of Late Pleistocene magnesian basalts in Kamchatka: Composition of erupted rocks // Volcanology and Seismology. 1999. V. 21. № 1. P. 45-66.    Аннотация
Most of the Kharchinskii and Zarechnyi products, as well as those of the Kharchinskii cinder cones, are magnesian rocks. Mineralogical data suggest that both the basaltic and the andesitic magma were rich in water (≥3-4 and >6-7 wt., respectively) and crystallized at high oxygen fugacity (2.0-2.5 orders of magnitude higher than the NNO buffer). These features, coupled with the geochemical characteristics of these basalts and andesites, indicate that they are similar to the rocks of Shiveluch, a volcano also located on the northern flank of the Northern volcanic group, but differ from the rocks of the other volcanoes of this group which are located further south. The Kharchinskii, Zarechnyi, and Shiveluch magnesian basalts differ from the rocks of the Klyuchevskoi volcano and Tolbachik lava field by their higher K, Ba, Sr and lower Ca, Sc, Yb contents at higher La/Yb, Ni/Sc, and La/Ta ratios, while their initial magmas were more hydrous and more oxidized.
http://repo.kscnet.ru/844/ [связанный ресурс]





 

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