| Mesón Group | |
| Type: | Group |
| Period: | Tremadoc |
| Age: | Cambrian-Tremadocian |
| Prilithology: | Sandstone, siltstone, limestone |
| Region: | Jujuy, Salta, Tucumán Potosí Department |
| Country: | Argentina Bolivia |
| Coordinates: | -23°N -65°W |
| Paleocoordinates: | -45.4°N -128.9°W |
| Subunits: | Lizoite Fm. Campanario Fm. Chahualmayoc Fm. |
| Underlies: | Santa Victoria Group |
| Overlies: | Puncoviscana Formation |
Mesón Group (Spanish; Castilian: Grupo Mesón) is a Cambrian to Early Ordovician sedimentary formation located in the Argentine Northwest and nearby parts of Bolivia. The group members rest unconformably on top of the Ediacaran–Cambrian Puncoviscana Formation. According to G.F. Aceñolaza, the Mesón Basin the sedimentary basin in which the Méson Group was deposited was located between the Arequipa and Río de la Plata Cratons.[1]
The Mesón Group comprises three formations: Chahualmayoc Formation at the top, Lizoite Formation at the base and Campanario Formation in-between.[2] The group is composed of sandstones, siltstones and limestones.[3] [4]
The group has provided fossils of: