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Pevzner M.M. The First Geological Data on the Chronology of Holocene Eruptive Activity in the Ichinskii Volcano (Sredinnyi Ridge, Kamchatka) // Doklady Earth Sciences. 2004. Vol. 395A. № 3. P. 335-337.
Piip B.I. Kronotzk ignimbrites in Kamchatka // Bulletin Volcanologique. 1963. Vol. 25. Vol. 1. P. 31-32. doi: 10.1007/BF02596535.
Plechov Pavel, Blundy Jon, Nekrylov Nikolay, Melekhova Elena, Shcherbakov Vasily, Tikhonova Margarita S. Petrology and volatile content of magmas erupted from Tolbachik Volcano, Kamchatka, 2012–13 // Journal of Volcanology and Geothermal Research. 2015. Vol. 307. P. 182 - 199. doi: 10.1016/j.jvolgeores.2015.08.011.
   Аннотация
Abstract We report petrography, and bulk rock, mineral and glass analyses of eruptive products of the 2012–13 eruption of Tolbachik volcano, Central Kamchatka Depression, Russia. Magmas are shoshonitic in composition, with phenocrysts of olivine and plagioclase; clinopyroxene phenocrysts are scarce. Samples collected as bombs from the active vent, from liquid lava at the active lava front, and as naturally solidified “toothpaste” lava allow us to quantify changes in porosity and crystallinity that took place during 5.25 km of lava flow and during solidification. Olivine-hosted melt inclusions from rapidly-cooled, mm-size tephra have near-constant {H2O} contents (1.19 ± 0.1 wt) over a wide range of {CO2} contents (< 900 ppm), consistent with degassing. The groundmass glasses from tephras lie at the shallow end of this degassing trend with 0.3 wt {H2O} and 50 ppm CO2. The presence of small saturation, rather than shrinkage, bubbles testifies to volatile saturation at the time of entrapment. Calculated saturation pressures are 0.3 to 1.7 kbar, in agreement with the depths of earthquake swarms during November 2012 (0.6 to 7.5 km below the volcano). Melt inclusions from slowly-cooled and hot-collected lavas have {H2O} contents that are lower by an order of magnitude than tephras, despite comparable {CO2} contents. We ascribe this to diffusive {H2O} loss through olivine host crystals during cooling. The absence of shrinkage bubbles in the inclusions accounts for the lack of reduction in dissolved {CO2} (and S and Cl). Melt inclusions from tephras experienced < 3 wt post-entrapment crystallisation. Melt inclusion entrapment temperatures are around 1080 °C. Compared to magmas erupted elsewhere in the Kluchevskoy Group, the 2012–13 Tolbachik magmas appear to derive from an unusually H2O-poor and K2O-rich basaltic parent.
Ponomareva V.V., Kyle P.R., Melekestsev I.V., Rinkleff P.G., Dirksen O.V., Sulerzhitsky L.D., Zaretskaia N.E., Rourke R. The 7600 (14C) year BP Kurile Lake caldera-forming eruption, Kamchatka, Russia: stratigraphy and field relationships // Journal of Volcanology and Geothermal Research. 2004. Vol. 136. № 3-4. P. 199-222. doi:10.1016/j.jvolgeores.2004.05.013.
   Аннотация
The 7600 14C-year-old Kurile Lake caldera-forming eruption (KO) in southern Kamchatka, Russia, produced a 7-km-wide caldera now mostly filled by the Kurile Lake. The KO eruption has a conservatively estimated tephra volume of 140–170 km3 making it the largest Holocene eruption in the Kurile–Kamchatka volcanic arc and ranking it among the Earth’s largest Holocene explosive eruptions. The eruptive sequence consists of three main units: (I) initial phreatoplinian deposits; (II) plinian fall deposits, and (III) a voluminous and extensive ignimbrite sheet and accompanying surge beds and co-ignimbrite fallout. The KO fall tephra was dispersed over an area of >3 million km2, mostly in a northwest direction. It is a valuable stratigraphic marker for southern Kamchatka, the Sea of Okhotsk, and a large part of the Asia mainland, where it has been identified as a f6 to 0.1 cm thick layer in terrestrial and lake sediments, 1000–1700 km from source. The ignimbrite, which constitutes a significant volume of the KO deposits, extends to the Sea of Okhotsk and the Pacific Ocean on either side of the peninsula, a distance of over 50 km from source. Fine co-ignimbrite ash was likely formed when the ignimbrite entered the sea and could account for the wide dispersal of the KO fall unit. Individual pumice clasts from the fall and surge deposits range from dacite to rhyolite, whereas pumice and scoria clasts in the ignimbrite range from basaltic andesite to rhyolite. Ignimbrite exposed west and south of the caldera is dominantly rhyolite, whereas north, east and southeast of the caldera it has a strong vertical compositional zonation from rhyolite at the base to basaltic andesite in the middle, and back to rhyolite at the top. Following the KO eruption, Iliinsky volcano formed within the northeastern part of the caldera producing basalt to dacite lavas and pyroclastic rocks compositionally related to the KO erupted products. Other post-caldera features include several extrusive domes, which form islands in Kurile Lake, submerged cinder cones and the huge silicic extrusive massif of Dikii Greben’ volcano.
Ponomareva V.V., Pendea I. Florin, Zelenin Egor, Portnyagin Maxim, Gorbach N.V., Pevzner M.M., Plechova A.A., Derkachev Alexander, Rogozin Aleksei, Garbe-Schönberg Dieter The first continuous late Pleistocene tephra record from Kamchatka Peninsula (NW Pacific) and its volcanological and paleogeographic implications // Quaternary Science Reviews. 2021. Vol. 257. 1. № Article 106838. P. 1-23. https://doi.org/10.1016/j.quascirev.2021.106838.
   Аннотация
The Kamchatka volcanic arc (NW Pacific) is one of the most productive arcs in the world, known for its highly explosive activity. At the same time, the Kamchatkan record of late Pleistocene explosive eruptions has remained fragmentary. Here we present the first continuous record of Kamchatkan explosive activity between ~12 and 30 ka, which includes ~70 eruptions and extends the earlier reconstructed Holocene sequence for another 20 ka. Our record is based on geochemical correlations of 14C-dated tephras that represent all Kamchatka volcanic zones and are buried in lacustrine deposits along the 200 km stretch of the Central Kamchatka Depression (CKD). The accompanying geochemical database of volcanic glass compositions includes 3104 new electron microprobe and 221 LA-ICP-MS analyses. The data show that during the period under study, large silicic explosive eruptions peaked at 30e25 ka. Later times were mostly associated with the moderate activity from northern CKD volcanoes Shiveluch and Zarechny. Our tephra record provides the first tephrochronological model for dating and correlating Central Kamchatka late Pleistocene deposits and gives us some insight into the timing of glacial advances in the Kliuchevskoi volcanic group and volcanic response to the onset of the Last Glacial Maximum and glacial unloading at its termination. In addition, studied sections of lacustrine deposits tightly linked by tephra markers suggest the existence of a large lake system within the CKD for ~20 kyr until its final discharge at ~12 ka BP.
Ponomareva V.V., Pevzner M.M., Melekestsev I.V. Large debris avalanches and associated eruptions in the Holocene eruptive history of Shiveluch Volcano, Kamchatka, Russia // Bulletin of Volcanology. 1998. Vol. 59. № 7. P. 490-505. doi: 10.1007/s004450050206.
   Аннотация
Shiveluch Volcano, located in the Central Kamchatka Depression, has experienced multiple flank failures during its lifetime, most recently in 1964. The overlapping deposits of at least 13 large Holocene debris avalanches cover an area of approximately 200 km2 of the southern sector of the volcano. Deposits of two debris avalanches associated with flank extrusive domes are, in addition, located on its western slope. The maximum travel distance of individual Holocene avalanches exceeds 20 km, and their volumes reach ∼3 km3. The deposits of most avalanches typically have a hummocky surface, are poorly sorted and graded, and contain angular heterogeneous rock fragments of various sizes surrounded by coarse to fine matrix. The deposits differ in color, indicating different sources on the edifice. Tephrochronological and radiocarbon dating of the avalanches shows that the first large Holocene avalanches were emplaced approximately 4530–4350 BC. From ∼2490 BC at least 13 avalanches occurred after intervals of 30–900 years. Six large avalanches were emplaced between 120 and 970 AD, with recurrence intervals of 30–340 years. All the debris avalanches were followed by eruptions that produced various types of pyroclastic deposits. Features of some surge deposits suggest that they might have originated as a result of directed blasts triggered by rockslides. Most avalanche deposits are composed of fresh andesitic rocks of extrusive domes, so the avalanches might have resulted from the high magma supply rate and the repetitive formation of the domes. No trace of the 1854 summit failure mentioned in historical records has been found beyond 8 km from the crater; perhaps witnesses exaggerated or misinterpreted the events.
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. Vol. 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. Vol. 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, 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.
Ponomareva Vera, Portnyagin Maxim, Davies Siwan M. Tephra without Borders: Far-Reaching Clues into Past Explosive Eruptions // Frontiers in Earth Science. 2015. Vol. 3. № 83. doi:10.3389/feart.2015.00083.
   Аннотация
This review is intended to highlight recent exciting advances in the study of distal (>100 km from the source) tephra and cryptotephra deposits and their potential application for volcanology. Geochemical correlations of tephra between proximal and distal locations have extended the geographical distribution of tephra over tens of millions square kilometers. Such correlations embark on the potential to reappraise volume and magnitude estimates of known eruptions. Cryptotephra investigations in marine, lake, and ice-core records also give rise to continuous chronicles of large explosive eruptions many of which were hitherto unknown. Tephra preservation within distal ice sheets and varved lake sediments permit precise dating of parent eruptions and provide new insight into the frequency of eruptions. Recent advances in analytical methods permit an examination of magmatic processes and the evolution of the whole volcanic belts at distances of hundreds and thousands of kilometers from source. Distal tephrochronology has much to offer volcanology and has the potential to significantly contribute to our understanding of sizes, recurrence intervals and geochemical make-up of the large explosive eruptions.