Coexisting clinopyroxene, garnet and amphibole from an "eclogite", Kakanui, New Zealand

A. J R White*, B. W. Chappell, P. Jakeš

*Corresponding author for this work

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Analyses of major and rare earth elements are presented for co-existing garnet, clinopyroxene, and amphibole from a Kakanui "eclogite". New and previously published analyses of garnets suggest a gradual increase of Fe and decrease of Mg from xenocrysts through garnet pyroxene eclogitic rocks to amphibole-rich eclogitic rocks. Clinopyroxenes show a parallel increase in Fe/Mg ratio and an increase in Jadeite component and decrease in Tschermak's component. These data indicate crystallization of garnet and clinopyroxene from an alkali-rich undersaturated magma and are consistent with the concept of eclogite fractionation, but rare earth data allow severe constraints to be placed on this process. The eclogites are considered to be deep-seated crystallization products of nephelinite, but eclogite fractionation is small and cannot account for the association of alkali basalt, basanite and nephelinite.

Original languageEnglish
Pages (from-to)185-191
Number of pages7
JournalContributions to Mineralogy and Petrology
Volume34
Issue number3
DOIs
Publication statusPublished - Sep 1972

    Fingerprint

Cite this