Missão Velha Formation
The Missão Velha Formation is an early Aptian geologic formation in northeastern Brazil's Araripe Basin where the states of Pernambuco, Piauí and Ceará come together. The formation is the middle stratigraphic unit of the Vale do Carirí Group, overlying the Brejo Santo Formation and overlain by the Abaiara Formation.
The formation comprises whitish fine-to-medium quartzose arenites, with subrounded to rounded grains, deposited in an alluvial fan environment 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.Geology
Fossil content
The following fossils were reported from the formation:
- Fish
- * Parvodus rugianus
- * Planohybodus peterboroughensis
- * Mawsonia cf. gigas
- * Acrodus sp.
- * Hybodus sp.
- * Lepidotes sp.
- * Neoceratodus sp.
- * Polyacrodus sp.
- * Vinctifer sp.
- * Lonchidiidae indet.
- Reptiles
- * Turtles
- ** Pelomedusidae indet.
- * Dinosaurs
- ** Sauropoda indet.
- ** Theropoda indet.
- * Loricata
- ** Mesosuchia indet.
- * Snakes
- ** Lacertilia indet.
- Amphibians
- * ?Amphibia indet.
- Ichnofossils
- * Carnosauria indet.
- * Ornithopoda indet.
- * Dinosauria indet.
