| details |
Late Llanvirnian |
Caradocian |
Baltic |
Nolvak,J. et al. Ordovician chitinozoan zones from Baltoscandia |
1993 |
| details |
Late Llanvirnian |
Caradocian |
Scandinavia |
Nolvak,J. et al. Ordovician chitinozoan zones from Baltoscandia |
1993 |
| details |
Late Idavere |
Oandu |
Norway |
Grahn,Y. et al. Caradocian and Ashgillian chitinozoan biostratigraphy of the Oslo Asker and Ringerike Districts, Oslo Region, Norway. |
1994 |
| details |
Late Llanvirnian |
Caradocian |
Canada(Arctic) |
Achab,A. et al. Ordovician chitinozoans from the Arctic Platform and the Franklinian Miogeosyncline in northern Canada |
1995 |
| details |
Uhaku |
|
USSR(Estonian SSR) |
Grahn,Y. et al. Precise chitinozoan dating of Ordovician impact events in Baltoscandia. |
1996 |
| details |
Late Ordovician |
|
Nevada |
Finney,S.C. et al. Late Ordovician mass extinction: A new perspective from stratigraphic sections in Central Nevada. |
1999 |
| details |
Middle Ordovician |
|
Australia(W.Australia) |
Winchester-Seeto,T. et al. Chitinozoans from the Middle Ordovician (Darriwilian) Goldwyer and Nita Formations, Canning Basin (Western Australia). |
2000 |