Well, I'm not convinced that there was an advanced civilization 120,000,000 years ago, but there are enough things popping up to make one wonder about highly advanced civilizations maybe 6,000- 10,000 years ago, before this earth was created (j/k).
Furthermore, perhaps some of that knowledge survivied for awhile into the civilizations that we have clearly verified. For example, rock structures have been found amongst the (I think) Mayan or Incan ruins that seem to have been cut or fitted with a laser like device, as best as we can tell.
Not enough evidence (at least that we know about) to prove anything, but it is enough to warrant keeping an open mind about the history of civilization as we thought that we knew it.
I don't discount a reality behind the Atlantis, Babel, and Deluge "myths."