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Holocene eruptive history of Ksudach volcanic massif, South Kamchatka: evolution of a large magmatic chamber (1999)
Volynets O.N., Ponomareva V.V., Braitseva O.A., Melekestsev I.V., Chen Ch.H. Holocene eruptive history of Ksudach volcanic massif, South Kamchatka: evolution of a large magmatic chamber // Journal of Volcanology and Geothermal Research. 1999. Vol. 91. P. 23-42. doi: 10.1016/S0377-0273(99)00049-9.
   Аннотация
The combination of geological, tephrochronological and geochemical studies is used to reconstruct the Holocene eruptive history of Ksudach volcanic massif, South Kamchatka and to trace the evolution of its magma. Ksudach is located in the frontal volcanic zone of Kamchatka. From Early Holocene till AD 240, the volcano had repetitive voluminous caldera-forming eruptions. Later they gave way to frequent moderate explosive–effusive eruptions that formed the Shtyubel' stratovolcano inside the nested calderas, and then to frequent larger explosive eruptions. Holocene eruptive products are low-K2O two pyroxene–plagioclase basaltic andesite to rhyodacite. Mineralogical, geochemical and isotopic data suggest that all the rock varieties originated as a result of fractionation of an initial mafic melt, with insignificant contamination and assimilation. Intensive mixing of the fractionating melts prior to, and during the course of the eruptions, is ubiquitous. The eruptions might have been triggered by repetitive injections of new mafic melt into the silicic chamber. Crystallization of the andesitic and rhyodacitic melts is estimated to have occurred at temperatures of 970–1010°C and 890–910°C, respectively, PH2O 1.5–2.0 kbar and fO2 close to the NNO buffer. According to the experimental data, such PH2O corresponds to 4.5%–5.5% of water in the melt, that is close to the content of water in the silicic hornblende-bearing magmas of the rear zone of the Kuril–Kamchatka arc. Hence, we suggest that the transition from pyroxene phenocryst associations of the frontal zone to the hornblende-bearing ones of the rear zone might be interpreted as reflecting higher temperatures of crystallization of the melts from the frontal zone rather than increasing water content in the rear zone magmas.
Holocene eruptive history of Shiveluch Volcano, Kamchatka Peninsula, Russia (2007)
Ponomareva V., Kyle P., Pevzner M., Sulerzhitsky L., Hartman M. Holocene eruptive history of Shiveluch Volcano, Kamchatka Peninsula, Russia / Volcanism and Subduction: The Kamchatka Region. Geophysical Monograph Series. Washington, D. C.: American Geophysical Union. 2007. Vol. 172. P. 263-282. doi:10.1029/172GM19.
   Аннотация
The Holocene eruptive history of Shiveluch volcano, Kamchatka Peninsula, has been reconstructed using geologic mapping, tephrochronology, radiocarbon dating, XRF and microprobe analyses. Eruptions of Shiveluch during the Holocene have occurred with irregular repose times alternating between periods of explosive activity and dome growth. The most intense volcanism, with frequent large and moderate eruptions occurred around 6500–6400 BC, 2250–2000 BC, and 50–650 AD, coincides with the all-Kamchatka peaks of volcanic activity. The current active period started around 900 BC; since then the large and moderate eruptions has been following each other in 50–400 yrs-long intervals. This persistent strong activity can be matched only by the early Holocene one.
Most Shiveluch eruptions during the Holocene produced medium-K, hornblendebearing andesitic material characterized by high MgO (2.3–6.8 wt %), Cr (47–520 ppm), Ni (18–106 ppm) and Sr (471–615 ppm), and low Y (> 18 ppm). Only two mafic tephras erupted about 6500 and 2000 BC, each within the period of most intense activity.
Many past eruptions from Shiveluch were larger and far more hazardous then the historical ones. The largest Holocene eruption occurred ∼1050 AD and yielded >2.5 km3 of tephra. More than 10 debris avalanches took place only in the second half of the Holocene. Extent of Shiveluch tephra falls exceeded 350 km; travel distance of pyroclastic density currents was > 22 km, and that of the debris avalanches ≤20 km.
Holocene tephra from the Chukchi-Alaskan margin, Arctic Ocean: Implications for sediment chronostratigraphy and volcanic history (2017)
Ponomareva Vera, Polyak Leonid, Portnyagin Maxim, Abbott Peter, Zelenin Egor, Vakhrameeva Polina, Garbe-Schönberg Dieter Holocene tephra from the Chukchi-Alaskan margin, Arctic Ocean: Implications for sediment chronostratigraphy and volcanic history // Quaternary Geochronology. 2017. doi:10.1016/j.quageo.2017.11.001.
   Аннотация
Developing chronologies for sediments in the Arctic Ocean and its continental margins is an important but challenging task. Tephrochronology is a promising tool for independent age control for Arctic marine sediments and here we present the results of a cryptotephra study of a Holocene sedimentary record from the Chukchi Sea. Volcanic glass shards were identified and quantified in sediment core HLY0501-01 and geochemically characterized with single-shard electron microprobe and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). This enabled us to reveal a continuous presence of glass shards with identifiable chemical compositions throughout the core. The major input of glasses into the sediments is geochemically fingerprinted to the ∼3.6 ka Aniakchak caldera II eruption (Alaska), which provides an important chronostratigraphic constraint for Holocene marine deposits in the Chukchi-Alaskan region and, potentially, farther away in the western Arctic Ocean. New findings of the Aniakchak II tephra permit a reevaluation of the eruption size and highlight the importance of this tephra as a hemispheric late Holocene marker. Other identified glasses likely originate from the late Pleistocene Dawson and Old Crow tephras while some cannot be correlated to certain eruptions. These are present in most of the analyzed samples, and form a continuous low-concentration background throughout the investigated record. A large proportion of these glasses are likely to have been reworked and brought to the depositional site by currents or other transportation agents, such as sea ice. Overall, our results demonstrate the potential for tephrochronology for improving and developing chronologies for Arctic Ocean marine records, however, at some sites reworking and redistribution of tephra may have a strong impact on the record of primary tephra deposition.
Holocene volcanism of Northern Kamchatka: The spatiotemporal aspect (2006)
Pevzner M.M. Holocene volcanism of Northern Kamchatka: The spatiotemporal aspect // Doklady Earth Sciences. 2006. Т. 409. № 2. С. 884-887. doi: 10.1134/S1028334X06060109.
How a tectonic earthquake may wake up volcanoes: Stress transfer during the 1996 earthquake–eruption sequence at the Karymsky Volcanic Group, Kamchatka (2007)
Walter Thomas R. How a tectonic earthquake may wake up volcanoes: Stress transfer during the 1996 earthquake–eruption sequence at the Karymsky Volcanic Group, Kamchatka // Earth and Planetary Science Letters. 2007. Vol. 264. № 3–4. P. 347 - 359. doi: 10.1016/j.epsl.2007.09.006.
   Аннотация
A large tectonic earthquake occurred on Kamchatka peninsular on New Year's Day of 1996 along a SW–NE trending fracture system. Just two days after the earthquake and at a distance of about 10–20 km to the north, a simultaneous eruption of two separate volcanoes followed. These were Karymsky Volcano and Akademia Nauk Volcano, the latter having its first eruption in historical records. In this paper I use numerical models in order to elaborate the static stress transfer between the earthquake and the volcanic system during the sequence that culminated in the January 1996 volcano-tectonic events. The models were designed to consider (i) the geodetically identified pre-eruptive period of doming in order to calculate stress changes at the nearby SW–NE trending fracture zone, and (ii) the January 1996 Mw 7.1 earthquake in order to calculate the dilatation and stress changes at the magma plumbing system. The results suggest that stress changes related to year-long inflation under the volcanic centers increased the Coulomb failure stress at the active faults and thus encouraged the earthquake. The earthquake, in turn, prompted dilatation at the magmatic system together with extensional normal stress at intruding N–S trending dikes. Also, field measurements confirmed the presence of N–S oriented fractures above the dike. Unclamping of the N–S oriented fractures allowed magma to propagate and eventually to trigger the twin-eruption at the volcanoes Karymsky and Akademia Nauk. These findings imply that successful hazard evaluations at volcanoes elsewhere require consideration of the seismo-tectonic framework and large earthquake cycles.
Hydrated sub-arc mantle: a source for the Kluchevskoy volcano, Kamchatka/Russia (2000)
Dorendorf Frank, Wiechert Uwe, Wörner Gerhard Hydrated sub-arc mantle: a source for the Kluchevskoy volcano, Kamchatka/Russia // Earth and Planetary Science Letters. 2000. Vol. 175. № 1–2. P. 69 - 86. doi: 10.1016/S0012-821X(99)00288-5.
   Аннотация
Oxygen isotope ratios of olivine and clinopyroxene phenocrysts from the Kluchevskoy volcano in Kamchatka have been studied by CO2 and ArF laser techniques. Measured δ18O values of 5.8–7.1‰ for olivine and 6.2–7.5‰ for clinopyroxene are significantly heavier than typical mantle values and cannot be explained by crustal assimilation or a contribution of oceanic sediments. Positive correlations between δ18O and fluid-mobile elements (Cs, Li, Sr, Rb, Ba, Th, U, LREE, K) and a lack of correlation with fluid-immobile elements (HFSE, HREE) suggest that 18O was introduced into the mantle source by a fluid from subducted altered oceanic basalt. This conclusion is supported by radiogenic isotopes (Sr, Nd, Pb). Mass balance excludes simple fluid-induced mantle melting. Instead, our observations are consistent with melting a mantle wedge which has been hydrated by 18O-rich fluids percolating through the mantle wedge. 18O-enriched fluids are derived from the subducted oceanic crust and the Emperor seamount chain, which is responsible for a particularly high fluid flux. This hydrated mantle wedge was subsequently involved in arc magmatism beneath Kluchevskoy by active intra-arc rifting.
Hydrogen isotope geochemistry and heat balance of a fumarolic system: Kudriavy volcano, Kuriles (2003)
Botcharnikov Roman E., Shmulovich Kirill I., Tkachenko Sergey I., Korzhinsky Mikhail A., Rybin Alexander V. Hydrogen isotope geochemistry and heat balance of a fumarolic system: Kudriavy volcano, Kuriles // Journal of Volcanology and Geothermal Research. 2003. Vol. 124. № 1-2. P. 45-66. doi:10.1016/S0377-0273(03)00043-X.
   Аннотация
The temperature and hydrogen isotope composition of the fumarolic gases have been studied at Kudriavy volcano, Kurile Islands, which is unique for investigating the processes of magma degassing because of the occurrence of numerous easily accessible fumaroles with a temperature range of 100–940°C. There are several local fumarolic fields with a total surface area of about 2600 m2 within the flattened crater of 200×600 m. Each fumarolic field is characterized by the occurrence of high- and low-temperature fumaroles with high gas discharges and steaming areas with lower temperatures. We have studied the thermal budget of the Kudriavy fumarolic system on the basis of the quantitative dependences of the hydrogen isotope ratio (D/H) and tritium concentration on the temperature of fumarolic gases and compared them with the calculated heat balance of mixing between hot magmatic gas and cold meteoric water. Hydrogen isotope composition (δD and 3H) shows a well expressed correlation with the gas temperature. Since D/H ratio and 3H are good indicators of water sources in volcanic areas, it suggests that the thermal budget of the fumarolic system is mostly controlled by the admixing of meteoric waters to magmatic gases. The convective mechanism of heat transfer in the hydrothermal system governs the maximum temperatures of local fumaroles and fumarolic fields. Low-temperature fumaroles at Kudriavy are thermally buffered by the boiling processes of meteoric waters in the mixing zone at pressures of 3–12 bar. These values may correspond to the hydrostatic pressure of water columns about 30–120 m in height in the volcanic edifice and hence to the depth of a mixing/boiling zone. Conductive heat transfer is governed by conductive heat exchange between gases and country rocks and appears to be responsible for the temperature distribution around a local fumarolic vent. The temperature and pressure of shallow degassing magma are estimated to be 1050°C and 2–3 bar, respectively. The length of the ‘main’ fumarolic gas conduit is estimated to be about 80 m from the linear correlation between maximal temperatures of fumarolic fields and distances to the highest-temperature ‘F-940’ fumarole. This value may correspond to the depth of an apical part of the magmatic chamber. The geometry of the crater zone at the Kudriavy summit and the model of convective gas cooling suggest different hydrostatic pressures in the hydrothermal system at the base of high- and low-temperature gas conduits. The depths of gas sources for low-temperature fumaroles are evaluated to be about 200 m at the periphery of the magma chamber.
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IVS FEB RAS Geoportal for integration and increasing availability of volcanological data (2013)
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
Identification of Ruptures and their Interaction with Hydrothermal–Magmatic Systems on Northern Paramushir Isl. (Kuril Islands, Russia): 3D Modeling of Tectonic Fragmentation (2020)
Khubaeva Olga, Bergal-Kuvikas Olga, Sidorov M.D. Identification of Ruptures and their Interaction with Hydrothermal–Magmatic Systems on Northern Paramushir Isl. (Kuril Islands, Russia): 3D Modeling of Tectonic Fragmentation // Geotecton. 2020. № 54. P. 785-796. doi: 10.1134/S0016852120060072.
Identification of Source Lithology at South Segment of Kamchatka Subduction Zone (2012)
Gavrilenko M., Herzberg C., Portnyagin M., Ozerov A. Identification of Source Lithology at South Segment of Kamchatka Subduction Zone // Abstract V31A-2761 presented at 2012 Fall Meeting, AGU, San Francisco, Calif., 3-7 Dec. 2012.