摘要
The pyrite-type FeO_(2)and FeO_(2)H were synthesized at the pressure-temperature conditions relevant to Earth’s deep lower mantle.Through the water-iron reaction,the pyrite-phase is a good candidate to explain the chemical heterogeneities and seismological anomalies at the bottom of the mantle.The solid solution of pyrite-type FeO_(2)and FeO_(2)H,namely the FeO_(2)Hx(0≤x≤1),is particularly interesting and introduces puzzling chemical states for both the O and H atoms in the deep mantle.While the role of H in the FeO_(2)–FeO_(2)H system has been primarily investigated,discrepancies remain.In this work,we summarize recent progress on the pyrite-phase,including FeO_(2),FeO_(2)H,and FeO_(2)Hx,which is critical for understanding the water cycling,redox equilibria,and compositional heterogenicities in the deep lower mantle.
基金
NSAF(Grant Nos.U1530402 and U1930401)
National Natural Science Foundation of China(NSFC,Grant No.17N1051-0213)
the National Science Foundation-Earth Sciences(EAR-1128799)
the Department of Energy-Geosciences(DE-FG02-94ER14466)
HPCAT operations are supported by DOE-NNSA’s Office of Experimental Sciences.APS is supported by DOEBES,under contract No.DE-AC02-06CH11357.
