O-18  search
BTisotopes
 .stable isotopes
 ..O-18
BToxygen
 .O-18
RTO-18/O-16
SNThis term has multiple hierarchies.
O-18/O-16  search
BTisotopes
 .stable isotopes
 ..O-18/O-16
BToxygen
 .O-18/O-16
UFO-16/O-18
RTisotope ratios
 paleoclimatology
 geologic thermometry
 O-16
 O-18
SNThis term has multiple hierarchies.