Chan Thomas has a unique take on Catastrophism. His ideas are similar to or derived from Charles Hapgood's crust displacement hypothesis. It appears Einstein lent credence to the idea, as he wrote the forward to Hapgood's book entitled The Earth's Shifting Crust, published in 1958.
True or not, it would seem to make sense of some things that modern theories are unable to address. Like for example, the flash froze woolly mammoth who died suddenly while eating buttercups, a flower that would not have grown in a frozen climate.
The CIA classified Chan's book after it's publication. The link I sent you is only the recently declassified portions. I'm not sure what he stumbled upon that was so sensitive, but it appears it was something verboten.