Bauval found that the Pyramids/Orion's Belt correlation was general and obvious in all epochs, but specific and exact in only one: At 10,450 BC – and… - Graham Hancock

The view of Professor Robert Schoch Schoch is a renowned figure, indeed notorious, for the case he's made, based on strict geological evidence, that the Great Sphinx of Giza bears the unmistakable erosion patterns of thousands of years of heavy rainfall.6 This means it has to be much older than 2500 BC (the orthodox date, when Egypt received no more rain than it does today) and must originally have been carved around the end of the Ice Age when the Nile valley was subjected to a long period of intense precipitation.

We know that relatively minor sea-level rises could set off major ice-sheet breakups, and it has been suggested by Stephen Oppenheimer that the tremendous earthquakes caused by isostatic rebalancing at the end of the Ice Age could have stirred up 'mountain-topping superwaves' in the northern regions of the Atlantic and Pacific Oceans. Other than Oppenheimer's own investigations, however, my impression is that while many brilliant individual scientists have studied individual post-glacial phenomena in great depth, very little has yet been done to investigate all these phenomena together as part of a complex system or to consider the effects on the earth and its human population of multiple, interacting cataclysms — floods, lands subsiding into the sea, earthquakes, volcanic eruptions — all occurring at the same time.

Quetzalcoatl, the Feathered Serpent, [...] came to teach [the ancient inhabitants of Mexico] the benefits of settled agriculture and the skills necessary to build temples. Although this deity is frequently depicted as a serpent, he is more often shown in human form — the serpent being his symbol and his alter ego — and is usually described as "a tall bearded white man" ... "a mysterious person ... a white man with a strong formation of body, broad forehead, large eyes and a flowing beard." Indeed, [...] the attributes and life history of Quetzalcoatl are so human that it is not improbable that he may have been an actual historical character ... the memory of whose benefactions lingered after his death, and whose personality was eventually deified. The same could very well be said of Oannes — and just like Oannes at the head of the Apkallu (likewise depicted as prominently bearded) it seems that Quetzalcoatl traveled with his own brotherhood of sages and magicians. We learn that they arrived in Mexico "from across the sea in a boat that moved by itself without paddles," and that Quetzalcoatl was regarded as having been "the founder of cities, the framer of laws and the teacher of the calendar."