The first fossils of Futabasaurus were found in the Irimazawa Member of the Tamayama Formation, Futaba Group, Fukushima Prefecture, Japan, dating to the Inoceramus amakusensis zone of the early Santonian.
formation | Command (military formation) | Elliot Formation | Lance Formation | Crato Formation | Chinle Formation | Two Medicine Formation | Tetsuji Tamayama | Tamayama, Iwate | Tamayama Formation | Missing Man Formation (band) | Missing Man Formation | Marcellus Formation | Kirkwood Formation | Gettysburg Formation | Clarens Formation | Whitby Mudstone Formation | Tunbridge Wells Sand Formation | Santana Formation | Phalanx formation | phalanx formation | Mahantango Formation | Leduc Formation | Identity formation | Hanson Formation | Formation (stratigraphy) | formation (stratigraphy) | Formation | Centre International de Formation Européenne | Bakken formation |