Kimberlite genesis from a common carbonate-rich primary melt modified by lithospheric mantle assimilation.

ABSTRACT: Quantifying the compositional evolution of mantle-derived melts from source to surface is fundamental for constraining the nature of primary melts and deep Earth composition. Despite abundant evidence for interaction between carbonate-rich melts, including diamondiferous kimberlites, and mantle wall rocks en route to surface, the effects of this interaction on melt compositions are poorly constrained. Here, we demonstrate a robust linear correlation between the Mg/Si ratios of kimberlites and their entrained mantle components and between Mg/Fe ratios of mantle-derived olivine cores and magmatic olivine rims in kimberlites worldwide. Combined with numerical modeling, these findings indicate that kimberlite melts with highly variable composition were broadly similar before lithosphere assimi

SUBMITTER: Giuliani A 

PROVIDER: S-EPMC7182416 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature