Pircancha Formation Explained

Pircancha Formation
Type:	Geological formation
Period:	Dapingian
Age:	Floian-Dapingian ~
Prilithology:	Mudstone
Otherlithology:	Shale, sandstone, pyrite
Region:	Tarija Department
Coordinates:	-21°N -65°W
Paleocoordinates:	-45.3°N -129.1°W
Thickness:	1800m (5,900feet)

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.^{[1] [2]} The fossil Pircanchaspis rinconensis is named after the formation.

Fossil content

The formation has provided the following fossils:

• Bactroceras boliviensis^[3]
• 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

• List of fossiliferous stratigraphic units in Bolivia

References

Bibliography

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

Notes and References

1. http://www.fossilworks.org/cgi-bin/bridge.pl?a=collectionSearch&collection_no=90413 "Rincon", "Escuela Seccional de Puesto Grande"
2. http://www.fossilworks.org/cgi-bin/bridge.pl?a=collectionSearch&collection_no=9103 Pircancha Fm., Tarija and Chilcayo
3. Aubrechtová, 2015