Catching up … the end of Permian extinction is now being blamed on a comet or asteroid strike, 252 million years ago (see http://phys.org/print294567573.html). The Araguainha crater in Bazil is where it is supposed to have left its mark – seel also www.sciencedirect.com/science/article/pii/S0016703712001457
Meanwhile, at http://phys.org/print294562653.html … the continental shelf off the NW coast of Australia was once a huge plain dissected by rivers and rugged outcrops of rock – it is now submerged. Using techniques learnt in the UK (in the North Sea) it is thought some archaeological treasures might be retrievable. High resolution surveys for oil and gas have shown up coastal lagoons, salt marshes, and river channels under the sea around the Dampier Archipelago.