In my view, there is no doubt that the Utnapishtim story preserves an oral tradition of Noah--you don't have too much difficulty with that because Noah and his family who all had first hand knowledge lived long after the flood.
The difficulty is presented by Gilgamesh himself. Who was he?
Noah lived 350 years after the flood. His son Shem, was still alive at the age of 446; Noah's grandson Arphaxad was 346 years old at the time of his grandfather's death.
Falstich has the Post Flood Summarian King's List starting less than 100 years after the flood but the first king is in Kish; the Sumarian's are united under the King in Urak about 75 years later so in Falstich's timeline, Gilgamesh would fall somewhere between 100 and 175 years after the flood.
Assuming 25 year generations (birth of the father to birth of the son), Gilgamesh could have been four or five generations removed from Noah and might well have located his great-great-great grandfather to have received the account denominated Utnapishtim.
Sure the Utnapishtim story is a little off the precise account in Genesis which Moses received from God but Noah was old; Gilgamesh was writing with a chisel, not a word processer.
Hapgood's analysis is intesting but speculative. The Summerian King's list (prior to the flood) has Summer in the same area. Other descriptions such as the rivers out of Eden; Eve's tomb in Mecca; and other artificats that predate the flood imply a common location.
The stories in Southeast Asia and the Pacific presumably migrated there with the population expansion. No doubt though that the flood is in the common history of ancient man--and the flood is not some local flood in the Black Sea.
Yes, I have been persuaded by Oppenheimer's argument. Prior to this change, I was a Black Sea as Noah's Flood story person
"The stories in Southeast Asia and the Pacific presumably migrated there with the population expansion. No doubt though that the flood is in the common history of ancient man--and the flood is not some local flood in the Black Sea."
The amazing thing, the expansion came from SE Asia. The original Caucasians probably came from China. And, Oppenheimer says the Gilgamesh writings mentions immigrants from the east ("wise men from the east"), I've not read Gilgamesh.
Dr Robert Schoch, (geologist/geophysist), has a book titled, Voyages Of The Pyramid Builders, that essentially has the same theme, that the world's first/great civilizations were 'seeded' from SE Asia, 7-8,000 years ago. (That was when the last Ice Age melt/surge occurred.) Both interesting and thought provoking books. I've just completed Oppenheimer's most recent book too, Out Of Eden.
Gilgamesh lived 2700-2500 BC.
The Black Sea flood was about 5600 BC.
This is a long time for oral tradition to survive, I think; however, people dated everything before and after the flood just as we now date everything before and after Jesus. I don't know how long oral tradition survives.
The flooding of the fresh water Black Sea with salt water from the Mediterranean may have displaced populations and sent them West. The sea filled with salt water and also would have sent water rushing up river channels resulting in massive flash-flooding inland along rivers.