Melting and defect transitions in FeO up to pressures of Earth's core-mantle boundary.

ABSTRACT: The high-pressure melting curve of FeO controls key aspects of Earth's deep interior and the evolution of rocky planets more broadly. However, existing melting studies on wüstite were conducted across a limited pressure range and exhibit substantial disagreement. Here we use an in-situ dual-technique approach that combines a suite of >1000 x-ray diffraction and synchrotron Mössbauer measurements to report the melting curve for Fe_1-xO wüstite to pressures of Earth's lowermost mantle. We further observe features in the data suggesting an order-disorder transition in the iron defect structure several hundred kelvin below melting. This solid-solid transition, suggested by decades of ambient pressure research, is detected across the full pressure range of the study (30 to 140 GPa). A

SUBMITTER: Dobrosavljevic VV 

PROVIDER: S-EPMC10643405 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature