The 2001-2004 dome-forming eruption of Shiveluch volcano, Kamchatka: Observation, petrological investigation and numerical modelling

Dirksen, O. and Humphreys, M. C. S. and Pletchov, P. and Melnik, O. and Demyanchuk, Y. and Sparks, R. S. J. and Mahony, S. (2006) The 2001-2004 dome-forming eruption of Shiveluch volcano, Kamchatka: Observation, petrological investigation and numerical modelling. Journal of Volcanology and Geothermal Research, 155 (3-4). pp. 201-226. DOI 10.1016/j.jvolgeores.2006.03.029

[img] PDF
Humphreys_J_VOL_GEO_155_2006.pdf
Restricted to Registered users only

Download (1MB)
Official URL: http://www.sciencedirect.com/science/article/B6VCS...

Abstract

There have been three episodes of lava dome growth at Shiveluch volcano, Kamchatka since the Plinian explosive eruption in 1964. The episodes in 1980–1981, 1993–1995 and 2001–2004 have discharged at least 0.27km3 of silicic andesite magma. A time-averaged mean extrusion rate of 0.2m3/s is thus estimated for the last 40years. Here the 2001–2004 activity is described and compared with the earlier episodes. The recent activity involved three pulses in extrusion rate and a transition to ongoing lava extrusion. Estimated magma temperatures are in the range 830 to 900°C, with 850°C as the best estimate, using the plagioclase −amphibole phenocryst assemblage and Fe−Ti oxides. Melt inclusions in amphibole and plagioclase have maximum water contents of 5.1wt.%, implying a minimum pressure of ∼155MPa for water-saturated conditions. The magma chamber depth is estimated to be about 5–6km or more, a result consistent with geophysical data. The thicknesses of opx–mt–amph reaction rims on olivine xenocrysts are used to estimate the residence time of olivine crystals in the shallow chamber in the range 2 months to 4 years, suggesting replenishment of deeper magma into the shallow chamber contemporaneous with eruption. The absence of decompression-driven breakdown rims around amphiboles indicates ascent times of less than 7days. Volcanological observations of the start of the 2001–2004 episode suggest approximately 16 days for the ascent time and a conduit equivalent to a cylinder of diameter approximately 53–71m. Application of a conduit flow model indicates that the magma chamber was replenished during the 2001–2004 eruption, consistent with the results of olivine reaction rims, and that the chamber has an estimated volume of order 7km3.

Item Type: Article
Uncontrolled Keywords: NIL AREP 2006 P
Subjects: 05 - Petrology - Igneous, Metamorphic and Volcanic Studies
Divisions: 05 - Petrology - Igneous, Metamorphic and Volcanic Studies
Journal or Publication Title: Journal of Volcanology and Geothermal Research
Volume: 155
Page Range: pp. 201-226
Identification Number: 10.1016/j.jvolgeores.2006.03.029
Depositing User: Sarah Humbert
Date Deposited: 16 Feb 2009 13:02
Last Modified: 23 Jul 2013 10:06
URI: http://eprints.esc.cam.ac.uk/id/eprint/248

Actions (login required)

View Item View Item

About cookies