The Earthquake Engineering Online Archive NISEE e-Library
| Oita, Japan earthquake, Apr. 22, 1975 | 17 |
| Oran, Algeria earthquake, Oct. 9, 1790 | 1 |
| Oroville, California earthquake, Aug. 1, 1975 | 8 |
| Osnabruck, Germany earthquake, Oct. 1, 1612 | 1 |
| Owens Valley, California earthquake, March 26, 1872 | 24 |