The Raigón Formation is a geologic formation in Uruguay dated between the Pliocene and Middle Pleistocene.[1]
In 1966, Uruguayan geologists Héctor Goso and Jorge Bossi defined the Raigón Formation, which they subdivided into the San José Member (the same as Francis and Mones' San José Formation) below and the San Bautista Member above.[2] In 1988, Álvaro Mones identified Lower Pleistocene levels in the San José Member.[3] In 2002, American geologist H. McDonald and Uruguayan paleontologist Daniel Perea suggested the formation may represent a wide timespan from the Montehermosan all the way to the Ensenadan.[4]
A notable finding was J. monesi, recovered in situ from a boulder originating in the San José Member. The boulder is made up of siltstone, claystone, and medium-grained and medium-to-conglomeratic psammite (a type of sandstone) intercalated with siltstone.[5]
The following fossils have been reported from the formation: