German Scientists Discover Iron Compounds Capable of Storing Water Nearly 3,000 km Beneath Earth's Surface

Breakthrough in Iron Compound Research

According to НВ — Техно: Researchers from Germany have identified two previously unknown iron compounds that can trap water deep within the Earth's interior. This finding sheds light on how some of the planet’s oldest water might be preserved in the mantle at depths approaching 2,900 kilometers, where extreme pressure and temperature conditions prevail. The study was conducted by the Bavarian Institute of Experimental Geochemistry and Geophysics in collaboration with the University of Bayreuth and the Max Planck Institute.

Details of the Experiment

To reveal these compounds, scientists subjected samples to immense pressures-around two million atmospheres-and heated them with lasers to approximately 2,500 °C, while compressing them between diamonds. Under these intense conditions, two iron oxyhydroxides, Fe5O12Hx and Fe7O12Hx, formed. Remarkably, these compounds appeared even when the samples contained almost no water but had trace amounts of hydrogen. As geophysicist Leonid Dubrovinsky explained,

“Only a tiny amount of hydrogen is needed for this to occur.”

According to the research, these iron compounds have the capacity to hold not only primordial water but also water transported deep into the mantle by tectonic plate movements.

“Because these minerals are very dense, they likely remain near the core-mantle boundary, effectively storing water over geological time scales,”

said Man Lianzhe, commenting on the study’s implications.

The findings were published in the journal Nature Geoscience and offer valuable insight into Earth's deep interior processes and the origins of its water.

This discovery represents a significant advance in our understanding of geological activity beneath the Earth's surface and the mechanisms behind water retention within the planet. Unlocking how iron compounds can sequester water may influence future research in geodynamics, mantle formation, and planetary science.

In addition to the recent discoveries regarding iron compounds, researchers continue to explore extreme conditions within Earth's depths. For instance, a groundbreaking study has revealed a new phase of superionic ice formed under significant heat and pressure, which may further our understanding of water's behavior in such environments. This fascinating research highlights the complex interactions between temperature, pressure, and water storage, shedding light on geological processes. To learn more about this innovative phase, check out the details in our article on the novel superionic ice phase.