Corrected entry: At the end of the film the NTI's entire ship ascends from the abyss to the surface. What happened to the rest of the sea floor that Bud, Lindsay, and Coffey had to race over during their battle? All of that seems to disappear when the mothership comes up.
jbrbbt
11th Aug 2021
Correction: Maybe I didn't understand what you are describing as an error. Only the ship ascends, the sea floor stays, well, on the sea floor. Since the ship is huge and has been there for a while, it is likely that a large part of the ship was covered by silt, making it appear to be sea floor.