Platinum-group element constraints on source composition and magma evolution of the Kerguelen Plateau using basalts from ODP Leg 183

In-situ geochemistry of sulfides in highly metasomatized mantle xenoliths from Kerguelen, southern Indian Ocean

“…7b). This geochemical signature is rather typical of mantle derived-magmas in which enrichments in PPGE's compared to IPGE's are observed (Rehkämper et al, 1999;Chazey and Neal, 2005;Bézos et al, 2005). We therefore envisage that the metasomatic medium that invaded the Group-I xenoliths, a strongly evolved silicate-bearing carbonate melt through repeated melt-rock reactions with the depleted lithospheric mantle beneath the Kerguelen Archipelago (Grégoire et al, 2000a), had relatively low contents of IPGE compared to Pd and Pt and was only capable of modifying the bulk-rock Pt and Pd budgets of these rocks.…”

Chalcophile elemental constraints on sulfide-saturated fractionation of Cenozoic basalts and andesites in SE China

“…Negative Ru anomalies of basalts and positive Ru anomalies of ultramafic rocks and chromites elsewhere in the world all suggest a close relationship between Ru and chromite (Angeli et al, 2001;Aulbach et al, 2004;Büchl et al, 2004;Chazey and Neal, 2005;Fiorentini et al, 2004;Handler and Bennett, 1999;Lorand et al, 2004;Philipp et al, 2001;Zhou et al, 1998). On the other hand, olivine crystals in some Sanshui samples with Ir enrichment have high Fo numbers (up to 85), suggesting relatively early crystallization of olivine.…”

Rhenium–osmium isotope and platinum-group elements in the Xinjie layered intrusion, SW China: Implications for source mantle composition, mantle evolution, PGE fractionation and mineralization

“…3), accounting for the original characteristics of the parental magmas generating the Xinjie intrusion. Negative Ru anomalies are known in the Emeishan basalts (Qi et al, 2008), SDRS basalts in Greenland (Philipp et al, 2001), Kerguelen Plateau basalts (Chazey and Neal, 2005) and the Agnew layered intrusion in Canada (Vogel et al, 1999), which are generally attributed to removal of laurite and/or Os-Ir-Ru alloys, together with chromite or olivine, from the parental magmas. Capobianco and Drake (1990) found that Ru was strongly portioned into spinel (D = 22-25).…”