The country of Oman hosts a strip of mantle rocks called peridotites in a formation 350 kilometers (217.5 miles) long and 30 kilometers (18.6 miles) wide.
Formed under searing heat and crushing pressure deep in the Earth, the rocks have unusual chemical properties when thrust up to the surface, including an affinity for carbon dioxide.
WATCH VIDEO: Ralph Keeling has spent 20 years in the family business: studying climate change.
"They are in disequilibrium with the surface," Juerg Matter of Columbia University said. "So they react really quickly with the atmosphere, rainwater and groundwater, and absorb CO2."
Traditionally, scientists have thought the process is self-limiting, stopping as newly-formed carbon minerals filled up spaces in the rocks.
But recently, Matter and a team of scientists have discovered that the usually gray rocks are laced with ribbons of red. These bands were produced by a mineral called listwanite, formed when the minerals in peridotite are carbonized.
If all of the mantle rocks exposed in Oman were converted in this way -- a highly improbably scenario, the team admitted -- they would lock away 4,000 years worth of human emissions.
Even a small fraction of that could make a dent in carbon dioxide levels in the atmosphere. Globally, peridotites occur in large enough amounts that carbon sequestration programs would make sense in places like Greece, Papua New Guinea and the west coast of the United States.
