The Permian-Triassic mass extinction is the largest in Earth's history. In the United States, the record of this critical geobiologic interval was long thought to be absent at a major sedimentary hiatus.
Matthew R. Saltzman and Alexa R.C. Sedlacek present new evidence that a more continuous record of the Permian-Triassic boundary extinction event in shallow marine, Bahamas-like carbonate platform deposits of the Confusion Range in western Utah that represent the ancient western margin of Pangaea.
This discovery is important because study of the causes of the Permian-Triassic extinction have come almost exclusively from the ancient Tethys region (localities in the Italian Alps, south China, Iran, Pakistan and others).
The controversy over the likely causes is in large part a debate over the interpretation of the associated carbon isotope excursion, which is present in western Utah based on our integrated carbon, strontium and sedimentologic studies.
Matthew R. Saltzman and Alexa R.C. Sedlacek, School of Earth Sciences, The Ohio State University, DOI:10.1130/G33906.1