Oxygen levels on early Earth rose, fell severa…

Seattle WA (SPX) Jul 10, 2018

Earth’s oxygen levels rose and fell more than once hundreds of millions of years before the planetwide success of the Great Oxidation Event about 2.4 billion years ago, new research from the University of Washington shows.

The evidence comes from a new study that indicates a second and much earlier “whiff” of oxygen in Earth’s distant past – in the atmosphere and on the surface of a large
Full article