Английская Википедия:Corda Formation

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Шаблон:Short description Шаблон:Infobox rockunit

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.

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

Origin

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

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

The Corda Formation consists largely of red sandstone, with very fine to medium grain size, rich in zeolites and iron oxide. Where whinstonesШаблон:Clarify 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

References

Шаблон:Reflist

Bibliography

  1. 1,0 1,1 1,2 1,3 Alves, 2010
  2. Weishampel et al., 2004
  3. Leonardi, 1994, p.53
  4. Leonardi, 1994, p.62