In order to find evidence of a 'global' flood, surely we'd need every area of earth tested. I wouldnt expect to find a global flood by looking at just north americal. However, there is evidence of great flooding in that region.
Exactly. The existence of any
one datable site that shows no evidence of a flood destroys forever the idea of the biblical flood.
The esistence of
local floods is of no help, and, so far, no-one has any evidence of anything other that local flooding.
It is worth noting that some cultures have no flood legends: most notably Egypt, who seemingly managed to survive unchanged despite being underwater throughout the biblical flood without having noticed this minor fact.
For Whigs admit no force but argument.