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 ~ | |
 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°06′S 44°42′W / 6.1°S 44.7°W |
| Approximate paleocoordinates | 2°24′S 12°06′W / 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 edit
The following fossils were reported from the formation:[2]
- Reptiles
- Fish
See also edit
- Takutu Formation, contemporaneous formation of northern Brazil and Guyana
References edit
- ^ De Castro et al., 2016, p.532
- ^ Pastos Bons Formation at Fossilworks.org
- ^ Montefeltro, 2013, p.835
- ^ Yabumoto, 2007
Bibliography edit
- 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. .