Braitseva O.A., Sulerzhitskii L.D., Ponomareva V.V., Melekestsev I.V. Geochronology of the greatest Holocene explosive eruptions in Kamchatka and their imprint on the Greenland glacier shield // Transactions (Doklady) of the Russian Academy of Sciences. Earth Science Sections. 1997. Vol. 352. № 1. P. 138-140.
Braitseva Olga A., Ponomareva Vera V., Sulerzhitsky Leopold D., Melekestsev Ivan V., Bailey John Holocene Key-Marker Tephra Layers in Kamchatka, Russia // Quaternary Research. 1997. Vol. 47. № 2. P. 125-139. doi:10.1006/qres.1996.1876.
Аннотация
Detailed tephrochronological studies in Kamchatka Peninsula, Russia, permitted documentation of 24 Holocene key-marker tephra layers related to the largest explosive eruptions from 11 volcanic centers. Each layer was traced for tens to hundreds of kilometers away from the source volcano; its stratigraphic position, area of dispersal, age, characteristic features of grain-size distribution, and chemical and mineral composition confirmed its identification. The most important marker tephra horizons covering a large part of the peninsula are (from north to south; ages given in 14C yr B.P.) SH2(≈1000 yr B.P.) and SH3(≈1400 yr B.P.) from Shiveluch volcano; KZ (≈7500 yr B.P.) from Kizimen volcano; KRM (≈7900 yr B.P.) from Karymsky caldera; KHG (≈7000 yr B.P.) from Khangar volcano; AV1(≈3500 yr B.P.), AV2(≈4000 yr B.P.), AV4(≈5500 yr B.P.), and AV5(≈5600 yr B.P.) from Avachinsky volcano; OP (≈1500 yr B.P.) from the Baraniy Amfiteatr crater at Opala volcano; KHD (≈2800 yr B.P.) from the “maar” at Khodutka volcano; KS1(≈1800 yr B.P.) and KS2(≈6000 yr B.P.) from the Ksudach calderas; KSht3(A.D. 1907) from Shtyubel cone in Ksudach volcanic massif; and KO (≈7700 yr B.P.) from the Kuril Lake-Iliinsky caldera. Tephra layers SH5(≈2600 yr B.P.) from Shiveluch volcano, AV3(≈4500 yr B.P.) from Avachinsky volcano, OPtr(≈4600 yr B.P.) from Opala volcano, KS3(≈6100 yr B.P.) and KS4(≈8800 yr B.P.) from Ksudach calderas, KSht1(≈1100 yr B.P.) from Shtyubel cone, and ZLT (≈4600 yr B.P.) from Iliinsky volcano cover smaller areas and have local stratigraphic value, as do the ash layers from the historically recorded eruptions of Shiveluch (SH1964) and Bezymianny (B1956) volcanoes. The dated tephra layers provide a record of the most voluminous explosive events in Kamchatka during the Holocene and form a tephrochronological timescale for dating and correlating various deposits.
Gorelchik V.I., Shirokov V.A., Firstov P.P., Chubarova O.S. Shiveluch volcano: seismicity, deep structure and forecasting eruptions (Kamchatka) // Journal of Volcanology and Geothermal Research. 1997. Vol. 78. № 1–2. P. 121 - 137. doi: 10.1016/S0377-0273(96)00108-4.
Аннотация
The deep structure, Wadati-Benioff zone (focal zone) geometry and the magma feeding system of Shiveluch volcano are investigated based on 1962–1994 detailed seismic surveillance. A focal zone beneath Shiveluch is dipping at an angle of 70° at depths of 100–200 km. Based on the revealed interrelations between seismicity at depths of 105–120 km and an extrusive phase of its eruptions in 1980 through 1994, it is inferred that primary magmas, periodically feeding the crustal chamber, are melted at depths of at least 100 km. An upsurge of extrusive-explosive activity at the volcano is preceded and accompanied by the increasing number and energy of both volcanic earthquakes beneath the dome and tectonic or volcano-tectonic earthquakes in the zones of NW-striking crustal faults near the volcano.The eruption of April 1993 has been the most powerful since 1964. It was successfully predicted based on interactive use of all seismic data. At the same time the influence of seismicity at depths of 105–120 km under the volcano on the style (and consequently on prediction) of its activity is decisive.
Lees J.M., Johnson J., Gordeev E.I., Batereau K., Ozerov A.Yu. Volcanic Explosions at Karymsky: A Broadband Experiment Around the cone // AGU Spring Meeting 1997 Abstracts. Baltimore, Maryland: AGU. 1997. P. S11C-06.
Ozerov A.Yu., Ariskin A.A., Kyle Ph., Bogoyavlenskaya G.E., Karpenko S.F. Petrological–Geochemical Model for Genetic Relationships between Basaltic and Andesitic Magmatism of Klyuchevskoi and Bezymyannyi Volcanoes, Kamchatka // Petrology. 1997. Vol. 5. № 6. P. 550–569
Ozerov A.Yu., Murav’ev Ya.D., Frisbie A.J. The 1996 Eruption of Karymsky Volcano and the Composition of its Products, Kamchatka, Russia // AGU Spring Meeting 1997 Abstracts. Baltimore, Maryland: AGU. 1997. P. V22A-04.
Volynets O.N., Ponomareva V.V., Babansky A.D. Magnesian Basalts of Shiveluch Andesite Volcano, Kamchatka // Petrology. 1997. Vol. 5. № 2. P. 206-221.
Аннотация
The eruptive history of the Shiveluch andesite volcano included two Holocene events, during which
the volcano erupted unusual rocks: medium-potassium, amphibole-bearing magnesian basalts (7600 years ago)
and high-potassium magnesian basalts with phlogopite and amphibole (3600 years ago). The volumes of tephra
were approximately 0.1 and 0.3 km3, respectively. Some of the mineralogical and geochemical features of the
Holocene basalts were inherited by the subsequent basaltic andesites and andesites. These are similar in Mg
variation ranges of olivine, clinopyroxene, and amphibole phenocrysts, high Mg contents, and high Cr and Ni
concentrations. This and the results of mass-balance calculations do not contradict the view that the Shiveluch
volcanic rocks originated during the crystal fractionation of Holocene basalt melts. However, the other
geochemical features of the Shiveluch rocks, e.g., their similar REE contents, cast doubt on the formation of
the magnesian basaltic andesites through fractional crystallization of magnesian basalt magma and suggest that
they originated as a result of interaction between magnesian basalt magma and a depleted mantle material at a
shallow depth. At the same time, the different mineral compositions of the Holocene medium- and high-potassium
basalts and the results of mass-balance calculations indicate that their parental magmas might be produced
by the melting of different rocks.
