Redox preconditioning deep cratonic lithosphere for kimberlite genesis - evidence from the central Slave Craton.

ABSTRACT: We present the first oxygen fugacity (fO₂) profile through the cratonic lithospheric mantle under the Panda kimberlite (Ekati Diamond Mine) in the Lac de Gras kimberlite field, central Slave Craton, northern Canada. Combining this data with new and existing data from garnet peridotite xenoliths from an almost coeval kimberlite (A154-N) at the nearby Diavik Diamond Mine demonstrates that the oxygen fugacity of the Slave cratonic mantle varies by several orders of magnitude as a function of depth and over short lateral distances. The lower part of the diamond-bearing Slave lithosphere (>120-130 km deep) has been oxidized by up to 4 log units in fO₂, and this is clearly linked to metasomatic enrichment. Such coupled enrichment and oxidation was likely caused by infiltrat

SUBMITTER: Yaxley GM 

PROVIDER: S-EPMC5428371 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature