Has anyone ever seen parts of a mountain on superflat world in Minecraft?

I'm on the Ps3, creative mode, flying through the map to discover it and all of a sudden there's a mountain with trees about 50 blocks in the air and i could see tunnels but it was real fast and like the land was there but invisible and you can go through it. Does that make any sense? Anyway it happened about three other times in the map like in each corner. It has just really confused me and it has been rackin my brain so if anyone can help shed some light on this ***** please.

Yes it was loading the chunck. Since your were flying fast the game didn't load the chunk fast enough. And you saw it. Thats all