| Pircancha Formation | |
|---|---|
| Stratigraphic range: Floian-Dapingian ~478–466 Ma PreꞒ Ꞓ O S D C P T J K Pg N | |
| Type | Geological formation |
| Thickness | 1,800 m (5,900 ft) |
| Lithology | |
| Primary | Mudstone |
| Other | Shale, sandstone, pyrite |
| Location | |
| Coordinates | 21°00′S 65°00′W / 21.0°S 65.0°W / -21.0; -65.0 |
| Approximate paleocoordinates | 45°18′S 129°06′W / 45.3°S 129.1°W / -45.3; -129.1 |
| Region | Tarija Department |
| Country |  Bolivia |
  Pircancha Formation (Bolivia) | |
The Pircancha Formation is a Floian to Dapingian geologic formation of southern Bolivia. The green mudstones, shales and sandstones were deposited in a shallow to open marine environment. The fossil Pircanchaspis rinconensis is named after the formation.
Fossil content
The formation has provided the following fossils:
- Bactroceras boliviensis
- Baltograptus deflexus, B. minutus
- Pircanchaspis rinconensis
- Pseudophyllograptus densus
- Tetragraptus cf. amii
- Didymograptus cf. suecicus
- Basilicus sp.
- Dinorthis sp.
- Famatinolithus sp.
- Geragnostus sp.
- Hoekaspis sp.
- Phyllograptus sp.
- Synhomalonotus sp.
See also
References
- "Rincon", "Escuela Seccional de Puesto Grande" at Fossilworks.org
- Pircancha Fm., Tarija and Chilcayo at Fossilworks.org
- Aubrechtová, 2015
Bibliography
- Aubrechtová, Martina (2015), "A revision of the Ordovician cephalopod Bactrites sandbergeri Barrande: systematic position and palaeobiogeography of Bactroceras", Geobios, 48 (3): 193–211, Bibcode:2015Geobi..48..193A, doi:10.1016/j.geobios.2015.03.002, retrieved 2019-03-03
Further reading
- B.-D. Erdtmann, B. Weber, H.-P. Schultze and S. Egenhoff. 2000. A possible agnathan plate from the lower Arenig (Lower Ordovician) of South Bolivia. Journal of Vertebrate Paleontology 20(2):394-399
- M. Toro and S. Fernandez. 1979. Los fósiles de la formación Pircancha aflorante en Chilcayo, Provincia Méndez - Depto. Tarija. Revista de la Academia Nacional de Ciencas de Bolivia 163-169