[blam]

"cross index: lost civilization theory."

About all I can add (quickly) to the discussion is that there was a severe worldwide 'tree ring' incident at 2354BC. This could have been part of a swarm? If not a swarm, it must have been pretty big event to affect the trees worldwide. (I'll see if I can find other things that may connect, later)

[blam]

....also, wasn't it around 2300BC that it was recorded that the Egyptians were so famished that they began to eat their children/babies? I think so. And, this is also the 'Ussher date' for Noah's Flood. (Nap time)

[RightWhale]

it must have been pretty big event to affect the trees worldwide

The Barringer Crater was created what, 50,000 years ago, and it's still in pretty good shape. It hit dry land, so erosion would be less than one that hit a marshy area.

Did they give the age of this Basra crater? They mentioned 4000 years, but was that the determined age of the crater?

[blam]

"The discovery of the crater has sparked great interest among scientists. Dr Benny Peiser, who lectures on the effects of meteor impacts at John Moores University, Liverpool, said it was one of the most significant discoveries in recent years and would corroborate research he and others have done. He said that craters recently found in Argentina date from around the same period - suggesting that the Earth may have been hit by a shower of large meteors at about the same time.

Ah ha. Maybe a meteor shower.