The formation comprises whitish fine-to-medium quartzosearenites, with subrounded to rounded grains, deposited in an alluvial fanenvironment during the syn-rift phase of the Araripe Basin.
The Missão Velha Formation has provided macrofossils of various genera of fish and reptiles as snakes, crocodylomorphs and turtles. Ichnofossils of dinosaurs were also discovered in the formation, as well as a tooth from an abelisaurid theropod.
^Felipe L. Pinheiro; Ana Emilia Q. de Figueiredo; Paula C. Dentzien-Dias; Daniel C. Fortier; Cesar L. Schultz; Maria Somália S. Viana (2013). "Planohybodus marki sp. nov., a new fresh-water hybodontid shark from the Early Cretaceous of northeastern Brazil". Cretaceous Research. 41: 210–216. doi:10.1016/j.cretres.2012.12.005.
^Ribeiro, Theo Baptista; Cupello, Camila; de Mayrink, Diogo; da Costa Pereira, Paulo Victor Luiz Gomes; Brito, Paulo Machado (15 April 2024). "A theropod tooth from the Missão Velha Formation (Late Jurassic-Early Cretaceous) of the Araripe Basin: oldest Brazilian Abelisaurid record". Historical Biology: 1–11. doi:10.1080/08912963.2024.2336982. ISSN0891-2963.
Carvalho, I. d. S.; Viana, M. S. S.; Filho, M. F. L. (1995), "Os icnofósseis de dinossauros da Bacia do Araripe (Crétaceo Inferior, Ceará-Brasil) - Dinosaur ichnofossils from the Araripe Basin (Lower Cretaceous, Ceará, Brazil)", Anais da Academia Brasileira de Ciências, 67: 433–442
Brito, P.M.; Bertini, R.J.; Martill, D.M.; Salles, L.O. (1994), Vertebrate fauna from the Missão Velha Formation (Lower Cretaceous, N.E. Brazil), Boletim do 3° sobre o Cretáceo do Brasil, Campus de Rio Claro/SP, UNESP, pp. 139–140