How can there be "beneficial conditions" at the bottom of a flood? They would have been under fifteen cubits of water.
Magical water, dont you remember? The kind that does not suffocate plants nor gets soil soggy.
What speaks volumes about biblical inerrancy is the fact that it forces a cogent being surrender every shred of honesty and integrity. Ken Ham is a shining example of that - reality has no value to him and what makes him totally evil is that he's actively spreading lies to children unlike those who think like him but are at least decent to keep their delusion to themselves.
What puzzles me a lot is that in order to make any "sense" of floodstories one has to invent alternative reality with water canopy or magical genetic material or 8 people being able to create big cities within few generations...