Hidden hydrogen: Does Earth hold vast stores of a renewable, carbon-free fuel?

IN THE SHADE of a mango tree, Mamadou Ngulo Konaré recounted the legendary event of his childhood. In 1987, well diggers had come to his village of Bourakébougou, Mali, to drill for water, but had given up on one dry borehole at a depth of 108 meters. “Meanwhile, wind was coming out of the hole,” Konaré told Denis Brière, a petrophysicist and vice president at Chapman Petroleum Engineering, in 2012. When one driller peered into the hole while smoking a cigarette, the wind exploded in his face.

“He didn’t die, but he was burned,” Konaré continued. “And now we had a huge fire. The color of the fire in daytime was like blue sparkling water and did not have black smoke pollution. The color of the fire at night was like shining gold, and all over the fields we could see each other in the light. … We were very afraid that our village would be destroyed.”