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Records: 2577
Late Holocene diatom assemblages in a lake-sediment core from Central Kamchatka, Russia (2012)
Hoff U., Dirksen O., Dirksen V., Herzschuh U., Hubberten H.-W., Meyer H., van den Bogaard C., Diekmann B. Late Holocene diatom assemblages in a lake-sediment core from Central Kamchatka, Russia // Journal of Paleolimnology. 2012. Vol. 47. Vol. 4. P. 549-560. doi: 10.1007/s10933-012-9580-y.
Fossil diatom assemblages in a sediment core from a small lake in Central Kamchatka (Russia) were used to reconstruct palaeoenvironmental conditions of the late Holocene. The waterbody may be a kettle lake that formed on a moraine of the Two-Yurts Lake Valley, located on the eastern slope of the Central Kamchatka Mountain Chain. At present, it is a seepage lake with no surficial outflow. Fossil diatom assemblages show an almost constant ratio between planktonic and periphytic forms throughout the record. Downcore variations in the relative abundances of diatom species enabled division of the core into four diatom assemblage zones, mainly related to changes in abundances of Aulacoseira subarctica, Stephanodiscus minutulus, and Discostella pseudostelligera and several benthic species. Associated variations in the composition and content of organic matter are consistent with the diatom stratigraphy. The oldest recovered sediments date to about 3220 BC. They lie below a sedimentation hiatus and likely include reworked deposits from nearby Two-Yurts Lake. The initial lake stage between 870 and 400 BC was characterized by acidic shallow-water conditions. Between 400 BC and AD 1400, lacustrine conditions were established, with highest contributions from planktonic diatoms. The interval between AD 1400 and 1900 might reflect summer cooling during the Little Ice Age, indicated by diatoms that prefer strong turbulence, nutrient recycling and cooler summer conditions. The timing of palaeolimnological changes generally fits the pattern of neoglacial cooling during the late Holocene on Kamchatka and in the neighbouring Sea of Okhotsk, mainly driven by the prevailing modes of regional atmospheric circulation.
Late Pleistocene to Holocene activity at Bakening volcano and surrounding monogenetic centers (Kamchatka): volcanic geology and geochemical evolution (2000)
Dorendorf F., Churikova T., Koloskov A., Wörner G. Late Pleistocene to Holocene activity at Bakening volcano and surrounding monogenetic centers (Kamchatka): volcanic geology and geochemical evolution // Journal of Volcanology and Geothermal Research. 2000. Vol. 104. № 1–4. P. 131 - 151. doi: 10.1016/S0377-0273(00)00203-1.
The different roles of variable mantle sources and intra-crustal differentiation processes at Bakening volcano (Kamchatka) and contemporaneous basaltic monogenetic centers are studied using major and trace elements and isotopic data.

Three suites of volcanic activity are recognized: (1) plateau basalts of Lower Pleistocene age; (2) andesites and dacites of the Bakening volcano, the New Bakening volcano dacitic centers nearby; and (3) contemporaneous basaltic cinder cones erupted along subduction zone—parallel N–S faults. Age-data show that the last eruptions in the Bakening area occurred only 600–1200 years ago, suggesting the volcano is potentially active.

Major element variations and petrographic observations provides evidence for a fractionation assemblage of olivine, clinopyroxene, ±plagioclase, ±magnetite (?) within the basaltic suite. The fractionation in the andesites and dacites is dominated by amphibole, clinopyroxene, orthopyroxene and plagioclase plus minor amounts of magnetite and apatite. The youngest cpx-opx-andesites of Bakening main volcano deviate from that trend. Their source was probably formed by mixing of basaltic magmas into the silicic magma chamber of the Bakening volcano. Overall trace element patterns as well as the Sr–Nd–Pb isotopic compositions are quite similar in all rocks despite large differences in their chemical composition (from basalt to rhyodacite). In detail however, the andesite–dacites of the central Bakening volcano show a stronger enrichment in the more incompatible elements and depletion in HREE compared to the monogenetic basaltic centers. This results in a crossing of the REE-pattern for the two suites. The decrease in the HREEs can be explained by amphibole fractionation. A slab component is less likely because it would result in fractionation of the HREE from each other, which is not observed. The higher relative amounts of LILE in the dacitic and the large scatter in the basaltic rocks must be the result of a variable source enrichment by slab-derived fluids overprinting a variable depleted mantle wedge. The plateau basalts are less depleted in HFSE and show a more fractionated HREE pattern. These lavas could either result from a slab component or the addition of an OIB-type enriched mantle in their source.
Late Pleistocene-Holocene Volcanism on the Kamchatka Peninsula, Northwest Pacific Region (2007)
Ponomareva V.V., Churikova T., Melekestsev I.V., Braitseva O.A., Pevzner M., Sulerzhitskii L. Late Pleistocene-Holocene Volcanism on the Kamchatka Peninsula, Northwest Pacific Region / Volcanism and Subduction: The Kamchatka Region. Washington, D. C.: American Geophysical Union. 2007. Vol. 172. P. 165-198. doi: 10.1029/172GM15.
Late Pleistocene-Holocene volcanism in Kamchatka results from the subduction of the
Pacific Plate under the peninsula and forms three volcanic belts arranged in en echelon manner
from southeast to northwest. The cross-arc extent of recent volcanism exceeds 250 km and
is one of the widest worldwide. All the belts are dominated by mafic rocks. Eruptives with
SiO2>57% constitute ~25% of the most productive Central Kamchatka Depression belt and
~30% of the Eastern volcanic front, but <10% of the least productive Sredinny Range belt.
All the Kamchatka volcanic rocks exhibit typical arc-type signatures and are represented
by basalt-rhyolite series differing in alkalis. Typical Kamchatka arc basalts display a strong
increase in LILE, LREE and HFSE from the front to the back-arc. La/Yb and Nb/Zr increase
from the arc front to the back arc while B/Li and As, Sb, B, Cl and S concentrations decrease.
The initial mantle source below Kamchatka ranges from N-MORB-like in the volcanic front
and Central Kamchatka Depression to more enriched in the back arc. Rocks from the Central
Kamchatka Depression range in 87Sr/86Sr ratios from 0.70334 to 0.70366, but have almost
constant Nd isotopic ratios (143Nd/144Nd 0.51307–0.51312). This correlates with the highest
U/Th ratios in these rocks and suggest the highest fluid-flux in the source region.
Holocene large eruptions and eruptive histories of individual Holocene volcanoes have been
studied with the help of tephrochronology and 14C dating that permits analysis of time-space
patterns of volcanic activity, evolution of the erupted products, and volcanic hazards.
Lateral variations in ash composition due to Eolian differentiation (1991)
Kirianov V.Yu., Solovieva N.A. Lateral variations in ash composition due to Eolian differentiation // Volcanology and Seismology. 1991. Vol. 12. № 4. P. 431-442.
Lava-Ice Interaction during the 1983 Klyuchevskoi Eruption (1988)
Vinogradov V.N., Muravyev Y.D. Lava-Ice Interaction during the 1983 Klyuchevskoi Eruption // Volcanology and Seismology. 1988. Vol. 7. № 1. P. 39-62.
Le Volcan Klychevskoy: son Activite de 1932 a 1988 et son Developpement Possible (1989)
Fedotov S.A., Khrenov A.P., Zharinov N.A. Le Volcan Klychevskoy: son Activite de 1932 a 1988 et son Developpement Possible // L` Association Volcanologique Europeenne. 1989. № 18. P. 11-24.
Long and Short Term Periodic Activity at Karymsky Volcano (1999)
Ozerov A., Lees J., Ispolatov J. Long and Short Term Periodic Activity at Karymsky Volcano // AGU Spring Meeting 1999. Eos Trans. AGU, xx (xx), Spring Meet. Suppl., Abstract. Boston, Massachusetts: AGU. 1999. P. V11D-09.
Long-lived Volcanic Centers of Kamchatka Geothermal Areas (2020)
Belousov Vladimir, Belousova Irina, Khubaeva Olga Long-lived Volcanic Centers of Kamchatka Geothermal Areas // World Geothermal Congress 2020+1. Reykjavik, Iceland: 2020. С. 1-8.
The current problems of hydrothermal processes and ore-forming systems are volcanic heat sources and mechanisms of heat
transfer. In Pauzhetsky, Semyachik and Mutnovsky geothermal areas in Kamchatka, active long-lived volcanic centers have been
studied, with which high-temperature hydrothermal systems are associated. In the Banno-Paratunsky geothermal area the Paleogene
and Neogene long-lived volcanic centers were identified, with which low-temperature hydrothermal systems are associated. The
geological history of the long-lived volcanic centers development is characterized by changes in their structure as a result of
hydrothermal-magmatic activity. These changes are manifested in the generation and evolution of magma chambers in the mantle
and in the Earth’s crust. Basalt melts of the mantle chambers transport the deep heat to the Earth’s surface through plane magmatic
channels without significant losses. The heat flow of these volcanic centers is short-lived and is characterized by a significant
capacity of ~8,000 kcal/km2s. The long-lived volcanic centers are characterized by the presence of magma chambers in the Earth's
crust. They shield the part of the mantle heat flow. Their thermal capacity on the Earth's surface is estimated from 1000 kcal/km2s
to 5000 kcal/km2s. It is assumed that a significant amount of thermal energy is retained in the long-lived volcanic centers. It is
spent on formation and activity of the chambers as well as the convective hydrothermal ore-forming systems. The evolution of such
centers is accompanied by the formation of complexes of metamorphic rocks which interaction with high-temperature mantle melts
is accompanied by redox reactions like combustion. As a result of these reactions, thermal energy is produced in such magma
chambers. A long-lived jet magmatic system is formed, and it provides the transfer of mantle heat. Heat transfer in the system is
accompanied by minimization of heat losses, accumulation of heat and its additional generation which is necessary for the heat
transfer in the structures with low thermal conductivity. The formation, evolution and extinction of magma chambers and reservoirs
in such heat-conducting structures are controlled by the thermophysical properties of the rocks, their geological structure and redox processes in them.
Gordeev E.I., Senyukov S.L., Girina O.A. MONITORING AND REPORTING OF KAMCHATKAN VOLCANIC ERUPTIONS // Proceedings of the 2nd International Conference on Volcanic Ash and Aviation Safety, June 21-24, 2004, Session 2. Alexandria, Virginia (USA): 2004. P. 43
Magma Chambers beneath the Klyuchevskoy Volcanic Group (2007)
Khubunaya S.A., Gontovaya L.I., Sobolev A.V., Nizkous I.V. Magma Chambers beneath the Klyuchevskoy Volcanic Group // Journal of Volcanology and Seismology. 2007. Vol. 1. № 2. P. 98-118. doi: 0.1134/S0742046307020029.
Поступила в редакцию 1. 11. 2006 г.
Методом сейсмической томографии построена объемная скоростная модель земной коры под Ключевской группой вулканов. Выделены аномалии скоростных параметров связанных с зонами магматического питания активных вулканов. Получены петрологические данные о составе, температуре и давлении генерации и кристаллизации родоначальных расплавов магнезиальных базальтов Ключевского вулкана. Родоначальный расплав отвечает пикриту (MgO=13-14%,мас) с предельным насыщением SiO2 (49-50%, мас.), высоким содержанием H2O (2,2-2.9%) и несовместимыми элементами (Sr, Rb, Ba, Hf). Он образуется при давлениях 15-20 кбар и температурах 1280-13200С. Его дальнейшая кристаллизация проходит в промежуточных магматических камерах при двух дискретных уровнях давлений (более 6 и 1-2 кбар). Результаты петрологических исследований находятся в хорошем соответствии с сейсмотомографической моделью.