作者: Georgios Aprilis , Anna Pakhomova , Stella Chariton , Saiana Khandarkhaeva , Caterina Melai
DOI: 10.3390/MIN10060542
关键词:
摘要: It is widely accepted that the lower mantle consists of mainly three major minerals—ferropericlase, bridgmanite and calcium silicate perovskite. Ferropericlase ((Mg,Fe)O) second most abundant three, comprising approximately 16–20 wt% mantle. The stability ferropericlase at conditions lowermost has been highly investigated, with controversial results. Amongst other reasons, experimental during laser heating (such as duration achieved temperature) have suggested a possible explanation for discrepancy. In this study, we investigate effect pulsed on ferropericlase, geochemically relevant composition Mg0.76Fe0.24O (Fp24) pressure corresponding to upper part wide temperature range. We report decomposition Fp24 formation high-pressure (Mg,Fe)3O4 phase CaTi2O4-type structure, well dissociation into Fe-rich Mg-rich phases induced by heating. Our results provide further arguments chemical more complex than initially thought, compositional inhomogeneity not only characteristic part, but includes depths shallow below transition zone.