| details |
Early Silurian |
|
USSR(Moscow Basin) |
Zalessky,M.D. On marine sapropelite of Silurian age, formed by blue-green alga. |
1917 |
| details |
Middle Eocene |
|
Colorado |
Bradley,W.H. Origin and microfossils of the oil shales of the Green River Formation of Colorado and Utah. |
1931 |
| details |
Middle Eocene |
|
Utah |
Bradley,W.H. Origin and microfossils of the oil shales of the Green River Formation of Colorado and Utah. |
1931 |
| details |
Precambriam |
|
India |
Manoharachary,C. et al. Problem of fungal contamination in Precambriam palaeobiology: a cautionary note:1. |
1990 |