Pebas Formation
| Pebas Formation | |
|---|---|
| Stratigraphic range: Early Aquitanian-Tortonian (Colhuehuapian-Huayquerian) ~ | |
| Underlies | Marañón Formation |
| Overlies | Chambira Formation |
| Area | 1,000,000 km2 (390,000 sq mi) |
| Thickness | ~350–1,074 m (1,148–3,524 ft) |
| Lithology | |
| Primary | Siltstone, mudstone |
| Other | Coal/lignite |
| Location | |
| Coordinates | 7°24′S 75°00′W / 7.4°S 75.0°W |
| Approximate paleocoordinates | 8°24′S 70°36′W / 8.4°S 70.6°W |
| Region | Amazon Basin |
| Country |  Brazil Colombia Ecuador Peru |
| Type section | |
| Named for | Pebas District |
The Pebas Formation is a lithostratigraphic unit of Miocene age, found in western Amazonia. The formation extends over 1,000,000 square kilometres (390,000 sq mi), including parts of Brazil, Peru, Ecuador and Colombia.[1] It is interpreted as representing the deposits of a lake ("Lake Pebas") or series of lakes, formed within the foreland basin of the Andes mountain belt. It is known for its abundant fossil ostracods and molluscs and an unusually diverse group of crocodylians.[2]
Fossil content
| Group | Fossils | Notes |
|---|---|---|
| Mammals | Dinomyidae indet., ?Octodontoidea indet. | |
| Reptiles | Caiman wannlangstoni, Gnatusuchus pebasensis, Gryposuchus pachakamue, Purussaurus neivensis, Kuttanacaiman iquitosensis, Mourasuchus atopus, Paleosuchus sp., Podocnemis sp., Gavialoidea indet. | |
| Fishes | cf. Hydrolycus sp., Leporinus sp., Potamotrygon sp., Pristis sp., Anostomidae indet. | |
| Insects | Macroteleia yaguarum, Sycorax peruensis |
References
- ^ Wesselingh et al., 2006
- ^ Sala Gismondi et al., 2006
- ^ a b c CTA-45 at Fossilworks.org
- ^ IQ114 at Fossilworks.org
- ^ Amazonian amber at Fossilworks.org
Bibliography
Further reading
- Template:Cite LSA
- Marcos C.Bissaro-Júnior, Leonardo Kerber, James L.Crowley, Ana M.Ribeiro, Renato P.Ghilardi, Edson Guilherme, Francisco R.Negri, Jonas P.Souza Filho, Annie S.Hsiou: "Detrital zircon U–Pb geochronology constrains the age of Brazilian Neogene deposits from Western Amazonia." Palaeogeography, Palaeoclimatology, Palaeoecology Volume 516, 15 February 2019, Pages 64–70 doi: 10.1016/j.palaeo.2018.11.032
Categories:
- Geologic formations of South America
- Geologic formations of Brazil
- Geologic formations of Colombia
- Geologic formations of Ecuador
- Geologic formations of Peru
- Miocene Series of South America
- Huayquerian
- Chasicoan
- Mayoan
- Laventan
- Friasian
- Colloncuran
- Santacrucian
- Colhuehuapian
- Neogene Brazil
- Neogene Colombia
- Neogene Ecuador
- Neogene Peru
- Fossiliferous stratigraphic units of South America
- Paleontology in Brazil
- Paleontology in Colombia
- Paleontology in Ecuador
- Paleontology in Peru
- Siltstone formations
- Mudstone formations
- Coal formations
- Lacustrine deposits