Mentioning a book by Charles Hapgood called "Earth's Shifting Crust". it is an interesting read.
A lot of people have quoted him as a "pole shift" theorist but that isn't quite right. His theory was that the poles stay in the same place but the earth's crust slips on the mantle every so often.
It is quite thought provoking.
It would explain how arctic regions were once temperate and why the poles seem to have been in different spots previously.
There is a correlation to agriculture starting at high elevations all around the world at the same time, this would be due to the massive waves generated by any slip wiping out anything near sea level.
And it would help explain why remnants of previous civilisations are so rare. They didn't just get flattened, they also got washed away.
He has also done a couple of other books; 'Maps of the Ancient Sea Kings' and' The Path to the Pole'. The first one is also good but I only just learned about the second.
To my knowledge there's nowhere at all in the Bible that says how old the earth is. I'm no theological expert, but I don't see the linkage between what it says and the age of the earth. The '6000 year old' claim is total garbage worked out by a monk in Ireland who made a series of bullshit assumptions then got quoted so many times that people took it seriously.