Bajo Barreal Formation
From Wikipedia, the free encyclopedia
| Bajo Barreal Formation | |
|---|---|
| Stratigraphic range: Mid Cenomanian-Late Turonian ~ | |
| Type | Geological formation |
| Unit of | Chubut Group |
| Underlies | Lago Colhué Huapí Formation |
| Overlies | Castillo Formation |
| Lithology | |
| Primary | Sandstone |
| Other | Claystone, mudstone, conglomerate, tuff |
| Location | |
| Coordinates | 45°18′S 69°36′W / 45.3°S 69.6°W |
| Approximate paleocoordinates | 51°36′S 46°42′W / 51.6°S 46.7°W |
| Region | Chubut, Santa Cruz |
| Country | Argentina |
| Extent | Golfo San Jorge Basin |
| Type section | |
| Named by | Teruggi & Rossetto |
| Year defined | 1963 |
  Bajo Barreal Formation (Argentina) | |
The Bajo Barreal Formation is a geological formation in the Golfo San Jorge Basin of Chubut and Santa Cruz, Argentina whose strata date back to the Middle Cenomanian to Late Turonian. The formation was first described by Teruggi & Rossetto in 1963.[1] The sandstones, claystones, mudstones, conglomerates and tuff were deposited in a fluvial environment.[2] The upper part of formation is laterally equivalent to the Yacimiento El Trébol and Meseta Espinosa Formation and the lower part to the Laguna Palacios, Cañadón Seco and Comodoro Rivadavia Formations. The Bajo Barreal Formation is a reservoir rock in the Golfo San Jorge Basin.[3]
Dinosaurs
Color key
|
Notes Uncertain or tentative taxa are in small text; |
Indeterminate abelisauroids and titanosaurs have been recovered from the formation.
Ornithopods
| Ornithopods reported from the Bajo Barreal Formation | |||||
|---|---|---|---|---|---|
| Genus | Species | Stratigraphic position | Material | Notes | Images |
| Notohypsilophodon[4] | N. comodorensis[4] | Lower | "Vertebrae, partial fore- and hindlimb"[5] | An elasmarian ornithopod. |  |
Sauropods
| Sauropods reported from the Bajo Barreal Formation | |||||
|---|---|---|---|---|---|
| Genus | Species | Stratigraphic position | Material | Notes | Images |
| Andesaurus[1] | A. sp.[1] | Lower | The most basal member of Titanosauria |  | |
| Campylodoniscus[4][6] | C. ameghinoi[4] | Lower | Maxilla with seven teeth.[7] |  | |
| Drusilasaura[8] | D. deseadensis | Upper | "four dorsal vertebrae, one sacral vertebra, six caudal vertebrae, left scapula, dorsal rib fragments, two haemapophyses and indeterminate fragments" | A titanosaur belonging to Lognkosauria |  |
| Epachthosaurus[4] | E. sciuttoi[4] | Lower | "Vertebrae [and] partial illium."[9] |  | |
| Katepensaurus | K. goicoecheai | Lower | Partial skeleton | A rebbachisaurid |  |
| Rebbachisauridae[10] | Indeterminate | Lower | Dorsal vertebra | Different from Katepensaurus. | |
| Sarmientosaurus[11] | S. musacchioi | Lower | A skull | A lithostrotian titanosaur with a skull similar to Brachiosaurus |  |
Theropods
| Theropods reported from the Bajo Barreal Formation | |||||
|---|---|---|---|---|---|
| Genus | Species | Stratigraphic position | Material | Notes | Images |
| Abelisauridae[1] | Indeterminate[1] | Lower | UNPSJB-PV247 A nearly complete left maxilla | Possibly distinct from Xenotarsosaurus. Estimated to be 6.21 metres (20.4 ft) long, larger than Xenotarsosaurus.[12] | |
| Abelisauridae[13] | Lower | partial skeleton | Different from all other comparable abelisaurids, but can't be compared with Xenotarsosaurus. | ||
| Aniksosaurus[4] | A. darwini[4] | Lower | A basal coelurosaur |  | |
| Megaraptoridae[14] | Indeterminate |
|
Two partial skeletons | ||
| Xenotarsosaurus[4] | X. bonapartei[4] | Lower | A vertebra and a nearly complete hind limb[15] | An abelisaur. |  |
- Other fossils