[e_engineer]

Blam, Here is the mapquest photo of the Bahamas. Do you mean the rounded areas where the water is deeper?

[blam]

Can't really compare from that picture but, I think so.

[blam]

I just had another thought about this possible impact.

A few years ago I read an article about some peculiar sand dunes in an isolated region of Australia. The guy working on the project said that they could have only been formed by a wind that was in excess of 200 mph and speculated that typhoons may have been more powerful in ancient times.

I now wonder if the wind could have come from Tunguska type impacts.