Image Courtesy: University of Cambridge
Scientists have developed a new global map that could help uncover previously unknown rare earth element deposits, offering a potential boost to the search for materials essential to modern technology and the clean energy transition.
The international research team, led by scientists from the University of Cambridge, identified a strong link between rare earth-rich volcanic rocks and the thickest, oldest sections of Earth’s continents. By combining rock chemistry data with seismic imaging of the planet’s interior, the researchers were able to pinpoint geological conditions that appear to favor the formation of rare earth deposits.
The findings, published in Nature Geoscience, could provide geologists with a powerful new tool for predicting where economically valuable deposits may be hidden. Rather than focusing on individual mining regions, the team analyzed global patterns, examining nearly 9,000 igneous rock samples collected from around the world.
Rare earth elements are crucial for manufacturing smartphones, electric vehicles, wind turbines, advanced electronics, and defense technologies. Demand for these materials is expected to rise sharply as countries invest in renewable energy infrastructure and seek alternatives to supply chains dominated by China.
To uncover the pattern, researchers combined their global rock database with seismic data generated by earthquake waves. These underground images revealed that rocks most likely to host rare earth concentrations tend to form along the steep boundaries of ancient continental lithosphere, the rigid outer shell of the Earth.
The study suggests that these thick sections of lithosphere create ideal conditions deep underground. High-pressure, relatively cool environments limit melting in the mantle, producing small pockets of magma that can become trapped and slowly evolve over millions of years. Repeated geological processes can then further concentrate rare earth elements until commercially viable deposits eventually form.
The research may have significant implications for mineral exploration. Instead of relying primarily on surface clues or historical discoveries, companies and governments could use the newly identified geological relationship to narrow the search for future deposits.
With global competition for critical minerals intensifying, improved methods of locating rare earth resources could become increasingly valuable. The researchers now plan to extend their work further back in geological time to study older rock formations that host many of the world’s largest known rare earth mines.
