Pastos Bons Formation

The Pastos Bons Formation is a Late Jurassic (Oxfordian to Kimmeridgian) geologic formation of the Parnaíba Basin in Maranhão, northeastern Brazil. The formation forms part of the sag phase of the basin. It overlies the Sardinha Formation and is overlain by the Mosquito Formation.[1] The fluvial to lacustrine sandstones and shales have provided fossils of a coelacanth fish, Parnaibaia maranhaoensis and a paralligatorid named after the formation, Batrachomimus pastosbonensis.

Pastos Bons Formation Stratigraphic range: Oxfordian-Kimmeridgian ~161–151 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Geologic map of the Parnaíba Basin with the Jurassic in red
Type	Geological formation
Underlies	Mosquitos Formation
Overlies	Sardinha Formation
Lithology
Primary	Sandstone
Other	Shale
Location
Coordinates	6.1°S 44.7°W
Approximate paleocoordinates	2.4°S 12.1°W
Region	Maranhão
Country	Brazil
Extent	Parnaíba Basin
Type section
Named for	Pastos Bons
Pastos Bons Formation (Brazil)

Fossil content

The following fossils were reported from the formation:[2]

• Reptiles
  • Batrachomimus pastosbonensis[3]
• Fish
  • Parnaibaia maranhaoensis[4]

See also

• Takutu Formation, contemporaneous formation of northern Brazil and Guyana

References

1. De Castro et al., 2016, p.532
2. Pastos Bons Formation at Fossilworks.org
3. Montefeltro, 2013, p.835
4. Yabumoto, 2007

Bibliography

• De Castro, David Lopes; Francisco Hilário Bezerra; Reinhardt Adolfo Fuck, and Roberta Mary Vidotti. 2016. Geophysical evidence of pre-sag rifting and post-rifting fault reactivation in the Parnaíba basin, Brazil. Solid Earth 7. 529–548. Accessed 2020-07-07.
• Montefeltro, F.C.; H. C. E. Larsson; M. A. G. França, and M. C. Langer. 2013. A new neosuchian with Asian affinities from the Jurassic of northeastern Brazil. Naturwissenschaften 100. 835–841. Accessed 2020-07-07.
• Yabumoto, Y. 2007. A New Mesozoic coelacanth from Brazil (Sarcopterygii, Actinistia). Paleontological Research 12. 329-343.