Institute of Volcanology and Seismology FEB RAS Repository
IVS FEB RAS
Search
Browse
IVS FEB RAS Items
Statistics
Instruction
Links

Catastrophic eruptions of the directed-blast type at Mount St. Helens, Bezymianny and Shiveluch volcanoes

Bogoyavlenskaya G.E., Braitseva O.A., Melekestsev I.V., Kirianov V.Yu., Dan Miller C. (1985) Catastrophic eruptions of the directed-blast type at Mount St. Helens, Bezymianny and Shiveluch volcanoes // Journal of Geodynamics. Vol. 3, No. 3-4. pp. 189-218. doi: 10.1016/0264-3707(85)90035-3.

Full text not available from this repository.

Abstract

This paper describes catastrophic eruptions of Mount St. Helens (1980), Bezymianny (1955–1956), and Shiveluch (1964) volcanoes. A detailed description of eruption stages and their products, as well as the quantitative characteristics of the eruptive process are given. The eruptions under study belong to the directed-blast type. This type is characterized by the catastrophic character of the climatic stage during which a directed blast, accompanied by edifice destruction, the profound ejection of juvenile pyroclastics and the formation of pyroclastic flows, occur. The climatic stage of all three eruptions has similar characteristics, such as duration, kinetic energy of blast (10^17−10^18 J), the initial velocity of debris ejection, morphology and size of newly-formed craters. But there are also certain differences. At Mount St. Helens the directed blast was preceeded by failure of the edifice and these events produced separable deposits, namely debris avalanche and directed blast deposits which are composed of different materials and have different volumes, thickness and distribution. At Bezymianny, failure did not precede the blast and the whole mass of debris of the old edifice was outburst only by blast. The resulting deposits, represented by the directed blast agglomerate and sand facies, have characteristics of both the debris avalanche and the blast deposit at Mount St. Helens. At Shiveluch directed-blast deposits are represented only by the directed-blast agglomerate; the directed-blast sand facies, or blast proper, seen at Mount St. Helens is absent. During the period of Plinian activity, the total volumes of juvenile material erupted at Mount St. Helens and at Besymianny were roughly comparable and exceeded the volume of juvenile material erupted at Shiveluch, However, the volume of pyroclastic-flow deposits erupted at Mount St. Helens was much less. The heat energy of all three eruptions is comparable: 1.3 × 10^18, 3.8−4.8 × 10^18 and 1 × 10^17 J for Shiveluch, Bezymianny, and Mount St. Helens, respectively.
Item Type: Article
Title: Catastrophic eruptions of the directed-blast type at Mount St. Helens, Bezymianny and Shiveluch volcanoes
Language: English
Journal or Publication Title: Journal of Geodynamics
ISSN Print: 02643707
Subjects: State scientific and technical information rubricator (ГРНТИ) > 38 ГЕОЛОГИЯ > 38.37 Петрография > 38.37.25 Вулканология
Volcanoes > 1 Volcanoes of the Kurile-Kamchatka Region > 1.1 Kamchatka > Bezymianny
Volcanoes > 1 Volcanoes of the Kurile-Kamchatka Region > 1.1 Kamchatka > Sheveluch
Volcanoes > 1 Volcanoes of the Kurile-Kamchatka Region > 1.1 Kamchatka > Sheveluch
Volcanoes > 1 Volcanoes of the Kurile-Kamchatka Region > 1.1 Kamchatka > Sheveluch
Volcanoes > 3 Volcanoes of the World > 3.3 North America > St. Helens (USA)
Depositing User: И.М. Романова
Date Deposited: 29 Nov 2013 04:48
Last Modified: 27 Sep 2015 04:04
URI: http://repo.kscnet.ru/id/eprint/1064

Actions (login required)

View Item View Item