PNNL

In fairy tales, magical spells can turn people and things to stone. In a desert in southeastern Washington state, it's a chemical reaction that converts carbon dioxide into stone.

Researchers at the Department of Energy's Pacific Northwest National Laboratory injected CO₂ into basalt lava flows a half mile underground near Wallula, Wash. In just two years, it had converted to a carbonate mineral or solid rock according to results published today in the journal Environmental Science & Technology Letters.

Conventional wisdom said it would take thousands of years for this to occur. PNNL researchers thought differently after their lab tests demonstrated that the unique geochemical nature of basalts quickly react with CO₂ to form carbonate minerals — something akin to limestone.

To prove the process operates the same deep underground, they injected nearly 1,000 tons of CO₂ in a field study. The results can help inform the discussion about whether the greenhouse gas can be safely and permanently stored in ancient basalt flows. Read more about the results on EurekAlert!