Helium is a minor biproduct of some natural gas production in the USA, Qatar, Algeria, Canada, Australia and a couple more countries. Discovery of helium provinces has been serendipitous. A critical element for society, helium is used in medical cryogenics, as an inert atmosphere in manufacturing, a breathing mixture with oxygen, for leak detection and other industrial processes. Recently demand has outstripped supply and reliance on serendipity to deliver new discoveries is clearly inadequate. In 2012 we began to develop a strategy for helium exploration, borrowing from the petroleum exploration playbook to determine source of helium, primary and secondary migration processes and characteristics for trapping. An opportunity to test our strategy emerged in late 2015. From Lake Rukwa in Tanzania there were reports of cold helium seeps. The East African Rift, Archean granitic basement with a substantial and recent thermal event fitted our criteria for helium generation and migration. The gases proved to be nitrogen/helium mixtures free of petroleum gases and with maximum helium concentrations of around 10% some 30 times greater than the commercial threshold used in the USA. Exploration drilling in now underway in Tanzania whilst research continues to refine our understanding of natural helium systems.
