A couple problems here:
1) assumptions:
the k/t line represents the biblical flood
there were no world wide floods after the bliblical flood
the biblical flood modified the geologic strata before it to create a false representation of a timeline
Given these assumptions, we should see a marked difference between the geologic strata between samples before and after the flood. Is this the case?
2)assumptions:
flora and fauna can be divided into 'clean' and 'unclean' groups
before the flood the 'unclean groups' were dominant
after the flood the 'clean' groups were dominant
this shift in dominance is due to artificial selection by noah, ie, 7 clean to 2 unclean
If this is true, then we should see higher genetic diversity amongst the clean groups than the unclean groups. Is this the case across the board? Do we see higher genetic diversity amongst cheetahs, apes, and wolves than over turtles, crocodiles, snakes, etc?
To me, these are both predictions by the flood model stated above. Both predictions must be met for the flood model to have validity since these predictions arise from core assumptions of it. standard nota bene: referencing the supernatural to explain away these predictions invalidates the hypothesis, supernatural is not science, it cannot be falsified or proven, and is therefore superstition and crackery.