A team of researchers from Durham University, the University of Oxford, and the exploration company Helium One has discovered a world-class helium gas field.
Helium is an odorless, tasteless and colorless gas that has unique properties.
It is the first of a group of elements often referred to as the noble gases.
Helium is a critical component in many fields of scientific research and is needed in a number of high-technology processes. However, known reserves are quickly running out.
Until now helium has never been found intentionally – being accidentally discovered in small quantities during oil and gas drilling.
Now, researchers from Norway and UK have developed a brand new exploration approach. The first use of this method has resulted in the discovery of a world-class helium gas field in Tanzania.
Their research, presented in Yokohama, Japan at the Goldschmidt Geochemistry Conference, shows that volcanic activity provides the intense heat necessary to release the gas from ancient, helium-bearing rocks.
“The high concentrations of helium in the region are likely related to the heating and fracturing of the Archean Tanzanian Craton and Proterozoic Mozambique Belt by the younger arms of the East African Rift System,” the scientists said.
“The distribution of high helium seeps along active faults shows increased communication between the shallow and deep crust. This combined with the presence of gas traps in the area suggests that there may be a significant helium resource.”
“We show that volcanoes in the Rift play an important role in the formation of viable helium reserves,” said lead author Dr. Diveena Danabalan, from Durham University.
“Volcanic activity likely provides the heat necessary to release the helium accumulated in ancient crustal rocks.”
“However, if gas traps are located too close to a given volcano, they run the risk of helium being heavily diluted by volcanic gases such as carbon dioxide, just as we see in thermal springs from the region.”
“We are now working to identify the goldilocks-zone between the ancient crust and the modern volcanoes where the balance between helium release and volcanic dilution is just right.”
“We sampled helium gas (and nitrogen) just bubbling out of the ground in the Tanzanian East African Rift Valley,” added co-author Prof. Chris Ballentine, from the University of Oxford.
“By combining our understanding of helium geochemistry with seismic images of gas trapping structures, independent experts have calculated a probable resource of 54 Billion Cubic Feet (BCf) in just one part of the Rift Valley.”
To put this discovery into perspective, global consumption of helium is about 8 BCf per year and the U.S. Federal Helium Reserve, which is the world’s largest supplier, has a current reserve of just 24.2 BCf.
“Total known reserves in the USA are around 153 BCf. 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,” Prof. Ballentine said.
Danabalan D. et al. 2016. New High-Grade Helium Discoveries in Tanzania. Goldschmidt Conference Abstracts, # 595
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