Scientists say they have found a large helium gas field in Tanzania.
With world supplies running out, the discovery is a “game-changer”, say geologists at Durham and Oxford universities.
Helium is used in hospitals in MRI scanners as well as in spacecrafts and radiation monitors.
Until now, the precious gas has been discovered only in small quantities during oil and gas drilling.
Using a new exploration approach, researchers found large quantities of helium within the Tanzanian East African Rift Valley.
They say resources in just one part of the Rift valley are enough to fill more than a million medical MRI scanners.
Professor Chris Ballentine, Department of Earth Sciences, University of Oxford, said: “This is a game changer for the future security of society’s helium needs and similar finds in the future may not be far away.”
And colleague Dr Pete Barry added: ‘We can apply this same strategy to other parts of the world with a similar geological history to find new helium resources. ”