Imma Perfetto
Cosmos science journalist
Scientists have simulated the actions of a volcano to conclude that extinct volcanoes across the globe are likely full of rare earth elements that could help supply the world’s growing demand for these difficult to extract resources.
According to new research from The Australian National University (ANU) and the University of the Chinese Academy of Sciences, the rare earth elements (REEs) occur in solidified iron-rich magma buried within the volcanoes.
REEs are essential for technologies key to modern life, such as smartphones, magnets, electric vehicles and renewable energy technologies.
“Rare earth elements aren’t that rare,” says Dr Michael Anenburg from ANU, co-author of the new study in Geochemical Perspectives Letters.
“They are similar in abundance to lead and copper. But breaking down and extracting these metals from the minerals they reside in is challenging and expensive.”
Anenburg and collaborators discovered the abundance of REEs in iron-rich volcanic rocks by simulating volcanic eruptions in the lab.
They sourced rocks similar to ones from iron-rich extinct volcanoes, put them into a pressurised furnace, and melted them at extremely high temperatures (800 to 1150 °C) to learn more about the minerals inside the rocks.
According to Anenburg, their findings suggest the iron-rich magma that solidified to form some extinct volcanoes is up to 100-times more efficient at concentrating rare earth metals than the magmas that commonly erupt from active volcanoes.
“We have never seen an iron-rich magma erupt from an active volcano, but we know some extinct volcanoes, which are millions of years old, had this enigmatic type of eruption,” says Anenburg.
“Our findings suggest that these iron-rich extinct volcanoes across the globe, such as El Laco in Chile, could be studied for the presence of rare earth elements.”
