San Juan Formation, Argentina
| San Juan Formation | |
|---|---|
| Stratigraphic range: Ordovician | |
| Type | Formation |
| Overlies | La Silla Formation |
| Thickness | 300–400 m (980–1,310 ft) |
| Lithology | |
| Primary | Limestone, marl |
| Other | Mudstone |
| Location | |
| Coordinates | 30°18′S 68°12′W / 30.3°S 68.2°W |
| Approximate paleocoordinates | 35°24′S 132°48′W / 35.4°S 132.8°W |
| Region | San Juan Province |
| Country |  Argentina |
| Extent | Precordillera |
| Type section | |
| Named for | San Juan Province |
The San Juan Formation (Spanish: Formación San Juan) is a geologic formation in Argentina. The formation comprising limestones, mudstones and marls was deposited in a shallow marine reefal environment and preserves many fossils dating back to the Ordovician period. The formation overlies the La Silla Formation and crops out in the Precordillera of San Juan Province.[1]
See also
References
- ^ Sánchez, Teresa M.; Carrera, Marcelo G.; Benedetto, Juan Luis (1996). "Variaciones faunísticas en el techo de la formación San Juan (Ordovícico Temprano, Precordillera Argentina): Significado paleoambiental". Ameghiniana (in Spanish). 33 (2): 185–200.
Further reading
- J. L. Benedetto. 2012. Gatosella, a new basal plectambonitoid brachiopod with undercut cardinal process from Middle Ordovician limestones of the Precordillera terrane, Argentina. Journal of Systematic Palaeontology 10(3):435-443
- M. G. Carrera. 2006. The new genus Multispongia (Porifera) from the Lower Ordovician limestones of the Argentine Precordillera. Ameghiniana 43(2):493-498
- M. G. Carrera. 2000. Epizoan-sponge Interactions in the Early Ordovician of the Argentine Precordillera. Palaios 15:261-272
- B. Kröger, M. S. Beresi, and E. Landing. 2007. Early orthoceratoid cephalopods from the Argentine Precordillera (Lower-Middle Ordovician). Journal of Paleontology 81(6):1266-1283