| details |
Late Llanvirnian |
Llandeilian |
Sweden |
Grahn,Y. Middle Ordovician chitinozoa from Oland |
1981 |
| details |
Late Arenigian |
Early Llanvirnian |
Sweden |
Grahn,Y. Chitinozoophoran palaeoecology in the Ordovician of Oland |
1982 |
| details |
Vendian |
Early Paleozoic |
USSR(Kazakh SSR) |
Sargaskaev,Z.S. et al. Some chitinozoans in the Kokzhotsk series of the Karatai range |
1988 |
| details |
Late Arenigian |
Caradocian |
Nd |
Uutela,A. Age and dispersal of sedimentary erratics on the coast of southwestern Finland. |
1989 |
| details |
Arenigian |
Llanvirnian |
USSR(Taldy-Kurganskaya) |
Zaslavskaya,N.M. et al. Ordovician chitinozoa of South Djungaria. (In: Problematic Fossils of the USSR. B.S.Sokolov, editors) |
1990 |
| details |
Late Arenigian |
Early Caradocian |
Baltic |
Nolvak,J. et al. Ordovician chitinozoan zones from Baltoscandia |
1993 |
| details |
Late Arenigian |
Early Caradocian |
Scandinavia |
Nolvak,J. et al. Ordovician chitinozoan zones from Baltoscandia |
1993 |
| details |
Late Kukruse |
Early Idavere |
Norway |
Grahn,Y. et al. Caradocian and Ashgillian chitinozoan biostratigraphy of the Oslo Asker and Ringerike Districts, Oslo Region, Norway. |
1994 |
| details |
Late Kukruse |
|
Sweden |
Grahn,Y. et al. Precise chitinozoan dating of Ordovician impact events in Baltoscandia. |
1996 |
| details |
Caradocian |
|
Poland |
Bednarczyk,W.S. Chitinozoa-bearing horizons in the Ordovician of Northern Poland in the light of conodont stratigraphy. |
1999 |
| details |
Caradocian |
|
Scotland(Dumfries) |
Zalasiewicz,J. et al. Submission of Hartfell Score (south Scotland) as a GSSP for the base of the middle stage of the Upper Ordovician Series. |
2004 |