Model suggests Earth's subsurface may hold up to 5.6 × 10⁶ million metric tons of natural hydrogen

A pair of geologists with the U.S. Geological Survey, Denver, has created a model that shows Earth's subsurface may hold up to 5.6 × 106 million metric tons of natural hydrogen. In their study, published in the journal Science Advances, Geoffrey Ellis and Sarah Gelman added factors to a geological model to produce estimates regarding the likely amount of hydrogen in parts of the Earth.