Dynamic of the lava flows during the Tolbachik Fissure eruption in 2012-2013 (Kamchatka) inferred from the satellite and ground-based observations (2014)
Melnikov Dmitry, Harris Andrew, Volynets Anna, Belousov Alexander, Belousova Marina Dynamic of the lava flows during the Tolbachik Fissure eruption in 2012-2013 (Kamchatka) inferred from the satellite and ground-based observations // EGU General Assembly 2014. 2014, Vienna, Austria. 2014.
Fissure eruption on the slope of Plosky Tolbachik volcano continued from November 27th, 2012 until September
2013. It was named as The Institute of Volcanology and Seismology 50th Anniversary Fissure Tolbachik Eruption.
The eruption started from the 5 km-long fissure opening and continued with the intensive lava effusion from it.
During the first two days of eruption the length of the lava flows was 9 km, and lava covered the area of 14.4
km2 (Gordeev et al., 2013). Lava discharge rate at this period was about 400 m3/sec. Two eruptive centers were
formed on the fissure – upper (Menyailov vent) and lower (Naboko vent), and lava gushed from them to the height
up to 200-300 meters. On December 1st, the Menyailov vent activity ceased, and the eruption concentrated at the
Naboko vent. Cinder cone was formed here, and lava flows effused from the base of the cone. Lava erupted from
the Menyailov vent, is different from the Naboko vent lava by higher silica content (SiO2 55.35 wt.% vs. 52.5
wt.%, respectively). That may be caused by the discharge of two levels of the magma chamber, fractionated to
a different extent. Morphologically, lava flows from the beginning of eruption until April 2013 were dominantly
aa-lava type, and from April until September 2013 pahoehoe type dominated.
For distinguishing of the dynamic of the lava flows the following methods were applied. As remote sensing methods
we used different satellite data – for specification of the area covered by lava flows, their length, temperature we
used Landsat 7 ETM+, Landsat 8, ASTER, EO-1 ALI and HYPERION. For time averaged discharge rate (TADR)
and lava flow area determination we used AVHRR data. We detected that in December 2013 lava discharge rate
varied from 120 to 40 m3/sec, and then it gradually decreased to average values 5-15 m3/sec and remained on this
level until the end of eruption. These data are confirmed by the ground-based observations, which were conducted
during the entire period of eruption. At the end of eruption in September 2013, lava flows area was about 36 km2, the maximum length of the lava flow – 15 km.
Dynamics of the 1800 14C yr BP caldera-forming Eruption of Ksudach Volcano, Kamchatka, Russia (2007)
Andrews B.J., Gardner J.E., Tait S., Ponomareva V.V., Melekestsev I.V. Dynamics of the 1800 14C yr BP caldera-forming Eruption of Ksudach Volcano, Kamchatka, Russia / Volcanism and Subduction: The Kamchatka Region. Geophysical Monograph Series. Washington, D. C.: American Geophysical Union. 2007. Vol. 172. P. 325-342. doi: 10.1029/GM172.
The 1800 14C yr BP Ksudach KS1 rhyodacite deposits present an opportunity to study the effects of caldera collapse on eruption dynamics and behavior. Stratigraphic relations indicate four Phases of eruption, Initial, Main, Lithic, and Gray. Well-sorted, reverse-graded pumice fall deposits overlying a silty ash compose the Initial Phase layers. The Main, Lithic, and Gray Phases are represented by pumice fall layers interbedded with pyroclastic flow and surge deposits (proximally) and co-ignimbrite ashes (distally). Although most of the deposit is <30 wt.% lithics, the Lithic Phase layers are >50 wt.% lithics. White and gray pumice are compositionally indistinguishable, however vesicle textures and microlite populations indicate faster ascent by the white pumice prior to eruption of the Gray Phase. The eruption volume is estimated as ∼8.5 km3 magma (dense rock equivalent) and ∼3.6 km3 lithics. Isopleth maps indicate mass flux ranged from 5–10×10^7 kg/s during the Initial Phase to >10^8 kg/s during the Main, Lithic, and Gray Phases. Caldera Collapse during the Lithic Phase is reflected by a large increase in lithic particles and the abrupt textural change from white to gray pumice; collapse began following eruption of ∼66% of the magma, and finished when ∼72% of the magma was erupted. Stratigraphic, granulometric, and component analyses indicate simultaneous eruption of buoyant plumes and non-buoyant flows during the Main, Lithic, and Gray Phases. Although mass flux did not change significantly following caldera collapse, the Gray Phase of eruption was dominated by non-buoyant flows in contrast to the earlier Phases that erupted mostly buoyant plumes.
Early Holocene M~6 explosive eruption from Plosky volcanic massif (Kamchatka) and its tephra as a link between terrestrial and marine paleoenvironmental records (2013)
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. Vol. 102. № 6. P. 1673-1699. doi:10.1007/s00531-013-0898-0.
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.
Earthquakes, properties of the upper mantle, and their connections with volcanism in Kamchatka (1971)
Fedotov S.A., Tokarev P.I. Earthquakes, properties of the upper mantle, and their connections with volcanism in Kamchatka / The Crust and Upper Mantle of the Pacific Area. // ХV Генеральная ассамблея Международного геодезического и геофизического союза. , Москва. 1971.
Ebeko volcano, Kuril Islands: eruptive history and potential volcanic hazards. Part I (1994)
Melekestsev I.V., Dvigalo V.N., Kirianov V.Yu., Kurbatov A.V., Nesmachnyi I.A. Ebeko volcano, Kuril Islands: eruptive history and potential volcanic hazards. Part I // Volcanology and Seismology. 1994. Vol. 15. № 3. P. 339-354.
The eruptive history of Ebeko Volcano is described since its origin about 2400 years ago until the beginning of the 17th century. Six stages of increased activity each lasting 200-300 years were separated by repose periods of the same duration. The eruption of juvenile material (lava and pyroclastics) took place at the first stage only (420-200 B.C.). All eruptions that followed were phreatic events of varying vigor. It is shown that, except for the first eruptive stage, the main volcanic hazard for the Ebeko area and the town of Severo-Kurilsk near by comes from large lahars and tephra fallout. -from Journal summary
Ebeko volcano, Kuril Islands: eruptive history and potential volcanic hazards. Part II (1994)
Melekestsev I.V., Dvigalo V.N., Kirianov V.Yu., Kurbatov A.V., Nesmachnyi I.A. Ebeko volcano, Kuril Islands: eruptive history and potential volcanic hazards. Part II // Volcanology and Seismology. 1994. Vol. 15. № 4. P. 411-430.
Consequences of the Ebeko eruptions in the 17th-20th centuries have been reconstructed, using historical records, tephrochronological study, and air photographs. It is shown that all eruptions were phreatic and phreatomagmatic with a heat source of a strongly heated dike-sill complex of more than 1 km3 volume. It is supposed that the main potential hazard for Severo-Kurilsk city and adjacent area may be connected with large-volume lahar flows along the Kuzminka and Matrosskaya Rivers, which are sourced on Ebeko Volcano. Lesser hazard is expected from ashfalls of this and other volcanoes of the north Kurils and south Kamchatka. -from Journal summary
По историческим сведениям, дополненным тефрохронологическими исследованиями и материалами аэрофотосъемок I960, 1987, 1988, 1990 гг. района в. Эбеко, детально восстановлены последствия его извержений XVII-XX вв. Показано, что все извержения были фреатическими и условно фреатомагматическими с источником теплового питания в виде сильно нагретого дайково-силлового комплекса объемом более 1 км . приуроченного к зоне растяжения ССВ (аз. 25°) простирания, вдоль которого расположены вулканы хр. Вернадского на о-в Парамушир. Предполагается, что в будущем главная опасность для г. Северо-Курильска и прилежащих участков связана с прохождением большеобъемных лахаров по рекам Кузьминка и Матросская, начинающихся на в. Эбеко, в меньшей степени - с пеплопадами этого и других вулканов Северных Курил и Южной Камчатки. Доказывается, что серьезная угроза городу может возникнуть при будущем извержении в. Эбеко типа его извержения 1934-1935 гг. Рекомендованы меры для защиты города.
Effects of caldera collapse on magma decompression rate: An example from the 1800 14C yr BP eruption of Ksudach Volcano, Kamchatka, Russia (2010)
Andrews Benjamin J., Gardner James E. Effects of caldera collapse on magma decompression rate: An example from the 1800 14C yr BP eruption of Ksudach Volcano, Kamchatka, Russia // Journal of Volcanology and Geothermal Research. 2010. Vol. 198. № 1–2. P. 205 - 216. doi: 10.1016/j.jvolgeores.2010.08.021.
Caldera collapse changes volcanic eruption behavior and mass flux. Many models of caldera formation predict that those changes in eruption dynamics result from changes in conduit and vent structure during and after collapse. Unfortunately, no previous studies have quantified or described how conduits change in response to caldera collapse. Changes in pumice texture coincident with caldera formation during the 1800 14C yr BP KS1 eruption of Ksudach Volcano, Kamchatka, provide an opportunity to constrain magma decompression rates before and after collapse and thus estimate changes in conduit geometry. Prior to caldera collapse, only white rhyodacite pumice with few microlites and elongate vesicles were erupted. Following collapse, only gray rhyodacite pumice containing abundant microlites and round vesicles were erupted. Bulk compositions, phase assemblages, phenocryst compositions, and geothermometry of the two pumice types are indistinguishable, thus the two pumice types originated from the same magma. Geothermobarometry and phase equilibria experiments indicate that magma was stored at 100–125 MPa and 895 ± 5 °C prior to eruption. Decompression experiments suggest microlite textures observed in the white pumice require decompression rates of > 0.01 MPa s− 1, whereas the textures of gray pumice require decompression at ~ 0.0025 MPa s− 1. Balancing those decompression rates with eruptive mass fluxes requires conduit size to have increased by a factor of ~ 4 during caldera collapse. Slower ascent through a broader conduit following collapse is also consistent with the change from highly stretched vesicles present in white pumice and to round vesicles in gray pumice. Numerical modeling suggests that the mass flux and low decompression rates during the Gray phase can be accommodated by the post-collapse conduit developing a very broad base and narrow upper region.
Effusive eruptions of silicic magmas and mechanism of the deep degassing of aqueous magmas (2004)
Maximov A.P. Effusive eruptions of silicic magmas and mechanism of the deep degassing of aqueous magmas // IV International Biennial Workshop on Subduction Processes emphasizing the Japan-Kurile-Kamchatka-Aleutian Arcs. August 21-27, 2004, Petropavlovsk-Kamchatsky. 2004. P. 148-151.
Emissions of trace elements during the 2012–2013 effusive eruption of Tolbachik volcano, Kamchatka: enrichment factors, partition coefficients and aerosol contribution (2014)
Zelenski M., Malik N., Taran Yu. Emissions of trace elements during the 2012–2013 effusive eruption of Tolbachik volcano, Kamchatka: enrichment factors, partition coefficients and aerosol contribution // Journal of Volcanology and Geothermal Research. 2014. Vol. 285. P. 136 - 149. doi: 10.1016/j.jvolgeores.2014.08.007.
Abstract Gases and aerosols from the 2012–13 effusive eruption of Tolbachik basaltic volcano, Kamchatka, were sampled in February and May, 2013, from a lava tube window located 300 m from the eruptive crater; temperature at the sampling point was 1060–1070 °C. The chemical and isotopic compositions of the sampled gases (92.4 H2O, 3.5 CO2, 2.3 SO2 on average; δD from − 25.0 to − 38.6‰) correspond to a typical volcanic arc gas without dilution by meteoric or hydrothermal water. Halogen contents in the gases (1.37 HCl, 0.5 HF) were higher than average arc values. The total amount of analyzed metallic and metalloid (trace) elements in the gas exceeded 665 ppm. Six most abundant trace elements, K (250 ppm), Na (220 ppm), Si (74 ppm), Br (48 ppm), Cu (21 ppm) and Fe (12 ppm), accounted for 95 of the total content of trace elements in the gas. The gases contained 24 ppb Re, 12 ppb Ag, 4.9 ppb Au and 0.45 ppb Pt. Refractory rock-forming elements (Mg, Al, Ca) and some other elements such as Ba and Th were transported mainly in the form of silicate microspheres and altered rock particles. The concentrations of metals in the eruptive Tolbachik gases are higher than the corresponding concentrations in high-temperature fumaroles worldwide, although the mutual ratios of the elements are approximately the same. The gas/magma partition coefficients of eleven elements exceed unity, including the non-metals F, S, Cl, Br, As, Se and Te and the rare metals Cd, Re, Tl and Bi. Despite the relatively low concentrations of trace elements in the volcanic gases at the highest temperatures, superficial magma degassing provides information on the sources and sinks of metals.