"...structure in Yucatan which led to the extinction of the dinosaurs..."
Except if you accept the argument of Chatergee (sp?) in India who believes that the Shiva crater was also formed about the same time, 65 million years ago, and as a much larger structure, 400 by 600 kilometers, probably was a much more significant factor in the demise of the dinosaurs. As his beliefs are being questioned by others, does anyone have any late info on this argument?