Late Aptian in origin. The Formation is formed by 3 members, the Carmópolis, Ibura and Oiterinhos members. The Carmópolis Member is formed by sandstones with minor intercalations of siltstones and shales and polymictic conglomerates. The Ibura Member contains a succession of halite, sylvinite and carnallite. The Oiteirinhos Member has an alternation of laminated calcilutites and shales. Fossils found in the formation include foraminifers, palynomorphs, ostracods, conchostraceans and fish remains.
