Subduction signature for quenched carbonatites from the deep lithosphere

Esmé van Achterbergh*, William L. Griffin, Chris G. Ryan, Suzanne Y. O'Reilly, Norman J. Pearson, Kevin Kivi, Buddy J. Doyle

*Corresponding author for this work

Research output: Contribution to journalArticle

55 Citations (Scopus)

Abstract

Quenched carbonate-silicate inclusions in lherzolitic clinopyroxene macrocrysts, derived from 200 km beneath the Slave craton in northern Canada, are interpreted as natural samples of mantle carbonatites. Oxygen, carbon, and strontium isotope data provide evidence for the involvement of subducted crustal material in the origin of these carbonatites, supporting suggestions that carbon recycling by subduction is an important prerequisite for carbonatite magmatism. The compositional range of the inclusions suggests that the parent melt was decreasing in silica content as it was trapped in the host crystal, a trend that is predicted experimentally. Isotopic disequilibrium between the carbonatitic inclusions and the host clinopyroxene indicates that they were trapped shortly before kimberlite eruption, suggesting a temporal link between the entrapment of the carbonatite in the host and the Paleocene eruption of the kimberlite.

Original languageEnglish
Pages (from-to)743-746
Number of pages4
JournalGeology
Volume30
Issue number8
DOIs
Publication statusPublished - Aug 2002
Externally publishedYes

    Fingerprint

Cite this