Malhada Vermelha Formation

The Malhada Vermelha Formation is an Early Cretaceous (Valanginian to Hauterivian) geologic formation in Ceará, northeastern Brazil. The formation preserves reptile, fish and ichnofossils.

Malhada Vermelha Formation
Stratigraphic range: Valanginian-Hauterivian ~138–130 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Type	Geological formation
Unit of	Iguatu Group
Underlies	Lima Campos Formation
Overlies	Quixoá Formation
Thickness	500–800 m (1,600–2,600 ft)
Lithology
Primary	Sandstone
Other	Siltstone
Location
Coordinates	6.3°S 39.1°W / -6.3; -39.1
Approximate paleocoordinates	4.5°S 6.2°W / -4.5; -6.2
Region	Ceará
Country	Brazil
Extent	Lima Campos & Malhada Vermelha Basins
Malhada Vermelha Formation (Brazil)

Description

The formation is characterized by a cyclic sequence of siltstones that are intercalated with fine to medium sandstones with the presence of festoon cross-stratification and climbing ripples, deposited in an alluvial environment in a hot semiarid paleoclimate.^[1]

The formation crops out in two minibasins, the Lima Campos and eponymous Malhada Vermelha Basins. The 500 to 800 metres (1,600 to 2,600 ft) thick formation overlies the Quixoá Formation and is overlain by the Lima Campos Formation.^[2]

Fossil content

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

• Fish
  • cf. Lepitodes sp.^[3]
  • Hybodontidae indet.^[3]
  • Planohybodus marki^[4]
• Reptiles
  • Crocodylomorpha indet.^[3]
• Ichnofossils
  • Taenidium barretti^[5]
  • Carnosauria indet.^[6]

See also

• Crato Formation
• Romualdo Formation
• Missão Velha Formation