| details |
Late Idavere |
Johvi |
Baltic |
Lindstrom,M. et al. Post-impact deposits in Tvaren, a marine Middle Ordovican Crater Southern of Stockholm, Sweden |
1994 |
| details |
Caradocian |
|
USSR(Estonian SSR) |
BergstrŠ¶m,S.M. et al. Nomenclature, stratigraphy, chemical fingerprinting and areal distribution of some Middle Ordovician K-Benonites in Baltoscandia. |
1995 |
| details |
Idavere |
|
USSR(Estonian SSR) |
Grahn,Y. et al. Precise chitinozoan dating of Ordovician impact events in Baltoscandia. |
1996 |
| details |
Harnagian |
Longvillian |
Nd |
Paris,F. Chitinozoan biostratigraphy and palaeoecology. (Principles and Applications. Applications. J.Jansonius and D.C.McGregor, editors.) |
1996 |
| details |
Early Caradocian |
|
Estonia |
Paris,F. et al. A revised chitinozoan classification |
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 |