[N] 2004 Bedout: A Possible End-Permian Impact Crater Offshore of Nw Australia
Becker, L., Poreda, R. J., Basu, A. R. , Pope, K. O., Harrison, T. M. , Nicholson, C. and Iasky, R. (2004) Bedout: A Possible End-Permian Impact Crater Offshore of Northwestern Australia. Science
Abstract: The Bedout High located on the northwestern continental margin of Australia has emerged as a prime candidate for an end Permian impact structure. Seismic imaging, gravity data and the identification of melt rocks and impact breccias from drill cores located on top of Bedout are consistent with the presence of a buried impact crater. The impact breccias contain nearly pure silica glass (SiO2), fractured and shock-melted plagioclases and spherulitic glass. The distribution of glass and shocked minerals over hundreds of meters of drill core implies that a melt sheet is present. Available gravity and seismic data suggest that the Bedout High represents the central uplift of a crater similar in size to Chicxulub. A plagioclase separate from the Lagrange-1 exploration well has an Ar/Ar age of 250.1 ± 4.5 million years. The location, size and age of the Bedout crater can account for reported occurrences of impact debris in Permian-Triassic boundary sediments worldwide.