Search SEDIS
| Data sets | Publications | Expeditions | Thesaurus | 
| Chad  | |
|---|---|
| BT | Africa | 
| .West Africa | |
| ..Chad | |
| NT | Kanem Chad | 
| UF | Chad Republic | 
| RT | Sahara | 
| Sahel | |
| Chad Basin | |
| Lake Chad | |
| Logone River | |
| Tibesti Massif | |
| Chad Basin  | |
|---|---|
| BT | Africa | 
| .Chad Basin | |
| RT | Cameroon | 
| Nigeria | |
| Niger | |
| Lake Chad | |
| Chad | |
| SN | Indexed with countries as applicable. | 
| Chad Republic  | |
|---|---|
| USE | Chad | 
| Chadak Uzbekistan  | |
|---|---|
| BT | Asia | 
| .Uzbekistan | |
| ..Chadak Uzbekistan | |
| SN | Village in E Uzbekistan. This term has multiple hierarchies. | 
| Chadobets Uplift  | |
|---|---|
| BT | Commonwealth of Independent States | 
| .Russian Federation | |
| ..Chadobets Uplift | |
| BT | Asia | 
| .Chadobets Uplift | |
| RT | Krasnoyarsk Russian Federation | 
| SN | SE Krasnoyarsk Kray in S Siberia. This term has multiple hierarchies. | 
| Chadron Arch  | |
|---|---|
| BT | United States | 
| .Chadron Arch | |
| RT | Nebraska | 
| South Dakota | |
| SN | NW Nebraska and SW South Dakota. Indexed with states as applicable. | 
| Chadron Formation  | |
|---|---|
| BT | Chronostratigraphic Units | 
| .Phanerozoic | |
| ..Cenozoic | |
| ...Paleogene | |
| ....Chadron Formation | |
| RT | Wyoming | 
| Colorado | |
| Nebraska | |
| South Dakota | |
| White River Group | |
| upper Eocene | |
| lower Oligocene | |
| Chadronian | |
| SN | Upper Eocene to lower Oligocene. In White River Group. NE Colorado, W Nebraska, W South Dakota, and E Wyoming. Age was previously considered lower Oligocene. Indexed with upper Eocene and/or lower Oligocene as applicable. | 
| Chadronian  | |
|---|---|
| BT | Chronostratigraphic Units | 
| .Phanerozoic | |
| ..Cenozoic | |
| ...Paleogene | |
| ....Eocene | |
| .....upper Eocene | |
| ......Chadronian | |
| RT | Chadron Formation | 
| SN | North America. Upper Eocene. Age previously considered lower Oligocene. |