A clip from the fun if flawed made for TV movie The Last Dinosaur. I remember watching this when it came on, and knew they had used Godzilla's roar for the T Rex. Didn't bother me, but at that time most people thought all Japanese monster movies were made by the same company.
It was also rumored to be stop-motion animation before we saw it, so some people were probably a bit disappointed. It certainly is an unique look at the lost world under the ice caps story. The performances really help propel the movie.