The term Caneleiras was adopted from the original denomination introduced by Tessari & Picada (1963 a, b and 1966) to designate a package of sedimentary rocks outcropping in Boa Vista region in the municipality of Encruzilhada do Sul, (Formation Caneleiras), for which they suggested a Devonian age. Further identification of fossils this seuqencia horizons with debris Scaphonix allowed position the upper portion of the sequence Mezóico being correlcionado range of Santa Maria Formation of Middle Triassic (Barnerena et al, 1985). The occurrence of basic intercalated effluents (Jost, 1981) and volcanic-elastic deposits in its upper section (Burguer Jr. et alii, 1988) characterize its vulcan-sedimentary nature. More recent studies by UNISINOS, during the students' graduation work, in the region of Piratini, Pinheiro Machado and Santana da Boa Vista