The mesas in the 'Bryce mesa' biome variant will generate on top of any rivers or lakes, floating directly above the water. This issue has been present since their first appearance in 0.9.5.
MCPE-8000
Mesas generate on top of water bodies in Bryce mesa biomes
Resolved
Fixed
0
Illidicia
(Unassigned)
Confirmed
Phone - iOS - iPhone 6 Plus
8.1.3
0.10.4, 0.10.5, 0.11.0, 0.11.0 Beta 14, 0.11.1
0.12.1 Pre-release
Retrieved
Relates to MC-30560