Bedout, near southern Australia, is a large, depression in the ocean basin approximately 200 km across, that could possibly be from a large bolder impact, some 250 mya. However, due to plate movement and the amount of time, it is undetermined as of now, if it is due indeed, to a bolide impact of mammoth proportions, or an oddity in our earth's structure. If it is indeed a bolide impact, this could account for the Permian-Triassic extinction. The possible impact crater was discovered in 1997 by Dr. Kenneth Rigsby, of the University of Wisconsin River Falls. His continuing research should yield many more clues in the years to come.