Petrology of mafic enclaves in the 2006–2012 eruptive products of Bezymianny Volcano, Kamchatka

This paper reports the results of the first comprehensive petrological study of mafic enclaves widespread in the products of recent (2006–2012) eruptions of Bezymianny Volcano, Kamchatka. Four types of mafic enclaves were distinguished on the basis of the composition and morphology of minerals, P–T...

Full description

Saved in:
Bibliographic Details
Published in:Petrology 2017-11, Vol.25 (6), p.592-614
Main Authors: Davydova, V. O., Shcherbakov, V. D., Plechov, P. Yu, Perepelov, A. B.
Format: Article
Language:English
Subjects:
Andesite
Ascent
Composition
Crystals
Earth and Environmental Science
Earth Sciences
Eruptions
Geochemistry
Lava
Magma
Mineral assemblages
Mineralogy
Minerals
Petrology
Plagioclase
Reservoirs
Volcanic eruptions
Volcanoes
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:This paper reports the results of the first comprehensive petrological study of mafic enclaves widespread in the products of recent (2006–2012) eruptions of Bezymianny Volcano, Kamchatka. Four types of mafic enclaves were distinguished on the basis of the composition and morphology of minerals, P–T conditions of formation of mineral assemblages, and structural and textural characteristics of the rocks. Disequilibrium assemblages of mafic enclaves indicate a complex structure of the magmatic plumbing system of the volcano, including a shallow chamber with andesite–basaltic andesite magmas and a deep reservoir filled in part with plagioclase–hornblende cumulates and fed by basic magmas with mantle harzburgite xenoliths. The mafic enclaves were formed at different levels of the magmatic plumbing system of the volcano and correspond to different degrees of mixing of interacting magmas. The most abundant enclaves were formed during magma ascent from the deep reservoir (960–1040°C, 5–9 kbar) into the shallow andesitic chamber (940–980°C). Enclaves of plagioclase–hornblende cumulates from the basic magmas feeding the deep reservoir ( T > 1090°C and P > 9 kbar) are much less common.
ISSN:0869-5911
1556-2085
DOI:10.1134/S0869591117060029