The Biblical Flood is dated in the Bible to about 5500 BC or 7500 BP. This corresponds to the last melting of the glaciers at the end of the last Ice Age and thus may be a true event. There was a Flood at this time.
It has also been found that 65,000 BP a disaster occurred where the world population shrank to six people and we are all descended from these six.
In view of the persistence of the story of the Asteroid collision with the moon 100,000.BP, I would suggest that the shrinking was not as severe or was caused by the collision and one of the dates is wrong.
The 65,000 BP date is from genetic variation measurements and the rate of genetic drift. This could have been slower in the past if radiation was less and thus this shrinking of the population may have been 100,000 years ago from a small population anyway but the event was so significant that the memory was preserved and all races on the earth would have had this tradition since they are all descended from these 6 survivors (the Bible says 8).
Was there another "Flood" 100,000 years ago caused by this collision that is remembered as Noahs Ark and the 8 are the survivors in his Ark?
Chris.