Floating stuff is normal as mappers tend to put models and terrain into a map so that it looks good from the playable area and not from above.

There are all kinds of rocks and logs and stuff under one of the other stock maps that looks like the mapper had them on the surface and must have dropped the terrain later and forgot to bring the models back up...

Seeing this stuff makes me feel better about my maps! LoL

Oops....sorry Voidsource I didnt answer your question. I think that is 'Cracked'

Go to the coordinate E1 in spectator and rise up about half way and you'll see it