Pridoli epoch - Helderbergian age
| International Chronostratigraphic Timescale | Devonian of Eastern North America | ||||
|---|---|---|---|---|---|
| Devonian | Late Devonian | Famennian | Conewangan/Conneautan/Canadaway | 358.86 | |
| Frasnian | West Fallsian/Sonyean | 372.15 | |||
| Middle Devonian | Givetian | Geneseean/Taghanican/Tioughniogan | Cazenovian | 382.31 | |
| Eifelian | Southwoodian | 387.95 | |||
| Early Devonian | Emsian | Sawkillian/Deer Parkian | Helderbergian | 393.47 | |
| Pragian | 410.62 | ||||
| Lochkovian | 413.02 | ||||
| Silurian | Pridoli | 419.62 | |||
| Ludlow | Ludfordian | 422.7 | |||
| Gorstian | 425 | ||||
| Wenlock | Homerian | 426.7 | |||
| Sheinwoodian | 430.6 | ||||
| Llandovery | Telychian | 432.9 | |||
| Aeronian | 438.6 | ||||
| Rhuddanian | 440.5 | ||||
| 443.1 | |||||