Ok are we talking about the lower or upper caves here?If lower there are two floor sections that do something. One is a pressure plate which opens a passage to a small room.
Another is a trap door that opens to a rope ladder that you can climb down onto a large boulder then descend into an underground lake area.
As for the upper caves there's a crack in a floor near a breakable wall but it has no purpose, its just a crack.
If one of these are not what you are describing I am not sure what you mean but have never had any other floor sections lead to anything.