Search SEDIS
| Data sets | Publications | Expeditions | Thesaurus |
Canadian Series  | |
|---|---|
| BT | Chronostratigraphic Units |
| .Phanerozoic | |
| ..Paleozoic | |
| ...Ordovician | |
| ....Lower Ordovician | |
| .....Canadian Series | |
| SN | Provincial series, North America. Above Croixian (Cambrian), below Champlainian. Before 1981, also search Canadian AND Ordovician. |