Missão Velha Formation

The Missão Velha Formation is a late Jurassic 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.

Missão Velha Formation
Stratigraphic range: Late Jurassic
~170–145 Ma
TypeGeological formation
Unit ofVale do Carirí Group
UnderliesAbaiara Formation
OverliesBreto Santo Formation
Thickness100–200 m (330–660 ft)
Lithology
PrimarySandstone
Location
Coordinates7°18′S 39°06′W / 7.3°S 39.1°W / -7.3; -39.1
Approximate paleocoordinates7°06′S 6°30′W / 7.1°S 6.5°W / -7.1; -6.5
RegionPernambuco, Piauí & Ceará
Country Brazil
ExtentAraripe Basin

Map of the Araripe Basin with the Missão Velha Formation in green

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

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Fossil content

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The following fossils were reported from the formation:[1]

See also

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References

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  1. ^ Missão Velha Formation at Fossilworks.org
  2. ^ a b c d e f g h i j k l m n o p Brito et al., 1994
  3. ^ a b c Carvalho et al., 1995

Bibliography

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Geology

Assine, Mario L. 1992. Análise estratigráfica da Bacia do Araripe, Nordeste do Brasil. Revista Brasileira de Geociências 22. 289–300. Accessed 2018-08-21.

Bétard, François; Jean-Pierre Peulvast; Alexsandra de Oliveira Magalhães; Maria de Lourdes Carvalho Neta, and Francisco Idalecio de Freitas. 2017. Araripe Basin: A Major Geodiversity Hotspot in Brazil. Geoheritage _. 1–18. Accessed 2018-08-21. Archived 21 August 2018 at the Wayback Machine

Scherer, C.M.d.S.; E.F. Jardim de Sá; V.C. Córdoba; D.d.C. Sousa; M.M. Aquino, and F.M.C. Cardoso. 2013. Tectono-Stratigraphic evolution of the upper Jurassic-Neocomian rift succession, Araripe Basin, Northeast Brazil. Journal of South American Geosciences _. 1–43. Accessed 2018-08-21.

Paleontology

Carvalho, I. d. S.; M. S. S. Viana, and M. F. L. Filho. 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.; R.J. Bertini; D.M. Martill, and L.O. Salles. 1994. Vertebrate fauna from the Missão Velha Formation (Lower Cretaceous, N.E. Brazil), 139-140. Boletim do 3° sobre o Cretáceo do Brasil, Campus de Rio Claro/SP, UNESP.