What caused Earth's largest mass extinction event? New evidence from the Permian-Triassic boundary in northeastern Utah

The discovery of a Permian-Triassic boundary section in northeastern Utah provided an opportunity to study the chemistry and geology associated with this event that led to one of the greatest mass extinctions on the planet. From 83% to 97% of the species living on the planet went extinct during this relatively short interval of geological time that defines the major geological boundary between the Paleozoic and Mesozoic Eras. The cause and...