Ancient oceanic oxygen

New research from geoscientists at the University of California, Riverside, corroborates recent evidence about the Great Oxidation Event. It has thus helped solve some outstanding questions surrounding the theory that the Earth's atmosphere underwent a dramatic rise in oxygen 2.4 billion years ago. An analysis of 2.5 billion-year-old black shales from Western Australia add to the evidence that oxygen production began in the Earth's oceans at least 100 million years before the GOE. The findings, which bring to light sulfidic conditions, could also have implications for understanding other geologic periods.