| Country: | Argentina   | 
| Province: | San Juan (Precordillera)   | 
| Locality: | Chavela, quebrada de   | 
| Layer: | Chavela Fm. | 
| Lower Boundary: | mid.--up.varcus Zone             [17,00], 389 million years   | 
| Upper Boundary: | UD2H--UD2I:(mamilliferum base)   [12,90], 370 million years   | 
| Georeference: |  |