Having check the satellite view of the location on Google I'll suggest he's clutching at straws.
Certainly it is a wee bit odd the way the Diamantina river performs a neat 180 degree circular arc. But highly improbable to be due to an impact crater - the mess of hills strewn across the middle of the "circle" do not resemble any impact structure I've seen before and suggest the origin of the diamantina river arc is more terrestrial in nature - ie. due to the gradient of the flood plain.
Given that the principal evidence in the article is in the geophysis data, it's possible that there will be no surface expression of the feature, other than an inherited drainage feature. I've co-authored papers on impact structures with Andrew Glickson, and given his experience in the field of impact structures I'd take this seriously, although it can only be confirmed with the drill bit.
Cheers,
Andrew
This is the one I reported to Dr Glickson a few years back (2012 I think). It still remains in the 'Definite maybe' basket, but only a field trip can confirm.
It's near Winton so very much in the region of the other anomaly (which we also discussed as it has been known about for some time). My crater is morphologically correct, but could be little more than the eroded head of a stream. I need to dust off my geology hammer and go take some samples to look for signs of impact damage in the crystal structures. I still plan to do it, but there is always something that spoils the trip - usually work...
