One usually doesn't see "Great Flood" and "legitmate archaeology" in the same conversation...
Question....How did the oldest civilization on the planet (Sumer according to scientists) have all the arts, science, math, writing, medicine, agriculture, world maps, sea navigation, astronomy, pictures of the solar system, etc ? Answer....they got it from the previous civilization.
I have to call shenanigans on this one; are you seriously asserting that ancient Sumer had "pictures of the solar system" and world maps? As for some of the rest (arts, math, etc.) it doesn't require an antediluvian civilization. People (such as the Sumerians) were perfectly capable of inventing such things as writing on their own.
Yep, but even in legitimate archaeology they recognize the Mediterranean filled abruptly when the natural dam at Gibraltar broke, the abrupt flooding of the Black Sea when the natural dam at the Bosphorus broke, the formation of the Scab-lands when the ice dam for lake Missoula broke, and the climate shift when the glaciers retreated enough to drain the Great Lakes region down the St Lawrence rather than the Mississippi.
Not to mention the world wide 300 ft sea level rise at the end of the last Ice Age that flooded places like Sundaland and what is now the English Channel.