Crystallization of basalt and andesite under high pressure hydrous conditions

Trevor H. Green, A. E. Ringwood

Research output: Contribution to journalArticleResearchpeer-review

Abstract

Experimental crystallization of synthetic high-alumina quartz tholeiite and basaltic andesite glasses at 9-10 kb under conditions of PH2O <Pload demonstrates that sub-silicic clinopyroxene, orthopyroxene and amphibole are the near-liquidus phases above 1000°C. Amphibole is the dominant phase at temperatures of about 960°C and less. Calcic plagioclase occurs nearer the solidus. In an andesite composition plagioclase and clinopyroxene are the near-liquidus phases at 940°C, joined by orthopyroxene, amphibole and garnet at lower temperatures. Electron microprobe analysis of phases crystallizing from the basalt allows calculation of the composition of liquid fractionates obtained under these conditions. The calculated liquid fractionate compositions follow the calc-alkaline trend and demonstrate that the calc-alkaline igneous rock suite may be derived by the fractional crystallization of basalt under hydrous conditions at 30-40 km depth (PH2O <Pload) or alternatively by the partial melting of amphibolite under similar conditions. In both cases the crystalline residuum will consist dominantly of amphibole, with subordinate clinopyroxene and orthopyroxene, and possibly minor calcic plagioclase and garnet, depending on the degree of fractionation.

LanguageEnglish
Pages481-489
Number of pages9
JournalEarth and Planetary Science Letters
Volume3
Issue numberC
Publication statusPublished - 1967
Externally publishedYes

Fingerprint

Amphibole Asbestos
andesite
amphiboles
Crystallization
basalt
amphibole
crystallization
plagioclase
orthopyroxene
clinopyroxene
liquidus
Garnets
garnets
garnet
Chemical analysis
Igneous rocks
Quartz
liquid
solidus
tholeiite

Cite this

@article{6fc085914d2847e1a14b2bf3d1687a9d,
title = "Crystallization of basalt and andesite under high pressure hydrous conditions",
abstract = "Experimental crystallization of synthetic high-alumina quartz tholeiite and basaltic andesite glasses at 9-10 kb under conditions of PH2O <Pload demonstrates that sub-silicic clinopyroxene, orthopyroxene and amphibole are the near-liquidus phases above 1000°C. Amphibole is the dominant phase at temperatures of about 960°C and less. Calcic plagioclase occurs nearer the solidus. In an andesite composition plagioclase and clinopyroxene are the near-liquidus phases at 940°C, joined by orthopyroxene, amphibole and garnet at lower temperatures. Electron microprobe analysis of phases crystallizing from the basalt allows calculation of the composition of liquid fractionates obtained under these conditions. The calculated liquid fractionate compositions follow the calc-alkaline trend and demonstrate that the calc-alkaline igneous rock suite may be derived by the fractional crystallization of basalt under hydrous conditions at 30-40 km depth (PH2O <Pload) or alternatively by the partial melting of amphibolite under similar conditions. In both cases the crystalline residuum will consist dominantly of amphibole, with subordinate clinopyroxene and orthopyroxene, and possibly minor calcic plagioclase and garnet, depending on the degree of fractionation.",
author = "Green, {Trevor H.} and Ringwood, {A. E.}",
year = "1967",
language = "English",
volume = "3",
pages = "481--489",
journal = "Earth and Planetary Science Letters",
issn = "0012-821X",
publisher = "Elsevier",
number = "C",

}

Crystallization of basalt and andesite under high pressure hydrous conditions. / Green, Trevor H.; Ringwood, A. E.

In: Earth and Planetary Science Letters, Vol. 3, No. C, 1967, p. 481-489.

Research output: Contribution to journalArticleResearchpeer-review

TY - JOUR

T1 - Crystallization of basalt and andesite under high pressure hydrous conditions

AU - Green, Trevor H.

AU - Ringwood, A. E.

PY - 1967

Y1 - 1967

N2 - Experimental crystallization of synthetic high-alumina quartz tholeiite and basaltic andesite glasses at 9-10 kb under conditions of PH2O <Pload demonstrates that sub-silicic clinopyroxene, orthopyroxene and amphibole are the near-liquidus phases above 1000°C. Amphibole is the dominant phase at temperatures of about 960°C and less. Calcic plagioclase occurs nearer the solidus. In an andesite composition plagioclase and clinopyroxene are the near-liquidus phases at 940°C, joined by orthopyroxene, amphibole and garnet at lower temperatures. Electron microprobe analysis of phases crystallizing from the basalt allows calculation of the composition of liquid fractionates obtained under these conditions. The calculated liquid fractionate compositions follow the calc-alkaline trend and demonstrate that the calc-alkaline igneous rock suite may be derived by the fractional crystallization of basalt under hydrous conditions at 30-40 km depth (PH2O <Pload) or alternatively by the partial melting of amphibolite under similar conditions. In both cases the crystalline residuum will consist dominantly of amphibole, with subordinate clinopyroxene and orthopyroxene, and possibly minor calcic plagioclase and garnet, depending on the degree of fractionation.

AB - Experimental crystallization of synthetic high-alumina quartz tholeiite and basaltic andesite glasses at 9-10 kb under conditions of PH2O <Pload demonstrates that sub-silicic clinopyroxene, orthopyroxene and amphibole are the near-liquidus phases above 1000°C. Amphibole is the dominant phase at temperatures of about 960°C and less. Calcic plagioclase occurs nearer the solidus. In an andesite composition plagioclase and clinopyroxene are the near-liquidus phases at 940°C, joined by orthopyroxene, amphibole and garnet at lower temperatures. Electron microprobe analysis of phases crystallizing from the basalt allows calculation of the composition of liquid fractionates obtained under these conditions. The calculated liquid fractionate compositions follow the calc-alkaline trend and demonstrate that the calc-alkaline igneous rock suite may be derived by the fractional crystallization of basalt under hydrous conditions at 30-40 km depth (PH2O <Pload) or alternatively by the partial melting of amphibolite under similar conditions. In both cases the crystalline residuum will consist dominantly of amphibole, with subordinate clinopyroxene and orthopyroxene, and possibly minor calcic plagioclase and garnet, depending on the degree of fractionation.

UR - http://www.scopus.com/inward/record.url?scp=49949140252&partnerID=8YFLogxK

M3 - Article

VL - 3

SP - 481

EP - 489

JO - Earth and Planetary Science Letters

T2 - Earth and Planetary Science Letters

JF - Earth and Planetary Science Letters

SN - 0012-821X

IS - C

ER -