The Corda Formation is a red sandstone geologic formation in the Parnaíba Basin in Tocantins, Brazil. It was formed during the Neoaptian to Eoalbian series of the Early Cretaceous.

Corda Formation
Stratigraphic range: Late Aptian-Early Albian
~115–110 Ma
TypeGeological formation
UnderliesSardinha Formation
OverliesItapecuru Formation
Lithology
PrimaryRed sandstone
Location
Coordinates5°42′S 47°30′W / 5.7°S 47.5°W / -5.7; -47.5
Approximate paleocoordinates5°06′S 14°48′W / 5.1°S 14.8°W / -5.1; -14.8
RegionTocantins
Country Brazil
ExtentParnaíba Basin
Type section
Named forCorda River
Corda Formation is located in Brazil
Corda Formation
Corda Formation (Brazil)

Large-scale fossil sauropod tracks have been reported from the formation.[1][2][3][4]

Origin

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The Corda Formation is characterized by reddish sandstones, that were probably deposited in windy deserts and fast flowing freshwater streams. Therefore, fossils are very rare.[1]

Occurrence

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This formation outcrops in the central part of the Parnaíba Basin, between the mouth of the Araguaia River in the west the Parnaíba River in the east.[1]

Lithology

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The Corda Formation consists largely of red sandstone, with very fine to medium grain size, rich in zeolites and iron oxide. Where whinstones[clarification needed] are overlaying fragments of this rock are also present. Typical structures of wind dunes (cross bedding, ripples, and grain flow) are common. This is consistent with deposition in a desert system.[1]

See also

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References

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  1. ^ a b c d Alves, 2010
  2. ^ Weishampel et al., 2004
  3. ^ Leonardi, 1994, p.53
  4. ^ Leonardi, 1994, p.62

Bibliography

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  • Alves, Y.M (2010), "Report on the Upper Permian and Lower Cretaceous fossiliferous localities vertebrates-bearing in the central north of Tocantins State, Brazil" (PDF), Brazilian Geographical Journal: Geosciences and Humanities research medium, Uberlândia, 1 (2): 372–386, retrieved 2019-02-16
  • Leonardi, Giuseppe (1994), Annotated Atlas of South America Tetrapod Footprints (Devonian to Holocene) with an appendix on Mexico and Central America, Ministerio de Minas e Energia - Companhia de Pesquisa de Recursos Minerais, Geological Service of Brazil, pp. 1–248, retrieved 2019-03-25
  • Weishampel, David B.; Dodson, Peter; Osmólska, Halszka (2004), The Dinosauria, 2nd edition, Berkeley: University of California Press, pp. 1–880, ISBN 0-520-24209-2, retrieved 2019-02-21