Putting Iron Oxide Under Pressure to Peer into the Deep Earth

In a real way, the depths of the Earth are more mysterious than the depths of space. While our instruments can peer almost to the very edges of the universe, and our space probes have ventured millions of miles into the galaxy, the deep interior of our own planet remains ever impenetrable and inaccessible. But seismic waves can still provide a detailed if indirect view into the Earth, moving at different speeds through various regions and materials, and revealing new mysteries. One of these concerns the region called the core-mantle boundary (CMB).

Formerly thought to consist of partially melted material, a more recent theory holds that the ULVZs are areas enriched in iron oxide (FeO), also known as the mineral wüstite. 

It was unclear, however, whether FeO could exist in a solid phase under the extreme heat and pressures of the CMB. To find out, a team of investigators from Caltech, University of Hawai'i, University of Chicago, and Argonne National Laboratory explored the phase diagram of FeO up to CMB conditions for the first time. Their work was published in Nature Communications.

Read the full article here Nature Communications.