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′S69°36′W / 45.3°S 69.6°W |
Approximate paleocoordinates | 51°36′S46°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 |
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]
Indeterminate abelisauroids and titanosaurs have been recovered from the formation
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 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 reported from the Bajo Barreal Formation | |||||
---|---|---|---|---|---|
Genus | Species | Stratigraphic position | Material | Notes | Images |
Abelisauridae [1] | Indeterminate [1] | Lower | 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 found in the formation include: [16] [17] [18]
Argyrosaurus is a genus of titanosaurian sauropod dinosaur that lived about 70 million years ago, during the Late Cretaceous Period of what is now Argentina.
Aeolosaurus is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous Period of what is now South America. Like most sauropods, it would have been a quadrupedal herbivore with a long neck and tail. Aeolosaurus is well known for a titanosaur, as it is represented by the remains of several individuals belonging to at least two species. However, like most titanosaurs, no remains of the skull are known. The holotype of Aeolosaurus rionegrinus consists of a series of seven tail vertebrae, as well as parts of both forelimbs and the right hindlimb. It was discovered in the Angostura Colorada Formation in Argentina, which dates from the Campanian stage of the Late Cretaceous, about 83 to 74 million years ago. The species A. maximus was transferred over to the new genus Arrudatitan in 2021.
Xenotarsosaurus is a genus of abelisaurid theropod dinosaur that lived during the Late Cretaceous of Argentina.
Notohypsilophodon is a genus of ornithopod dinosaur from the Late Cretaceous of Argentina. It was described as the only "hypsilophodont" known from South America, although this assessment is not universally supported, and Gasparinisaura is now believed to have been a basal euornithopod as well.
Secernosaurus is a genus of herbivorous dinosaur. Secernosaurus was a hadrosaur, a "duck-billed" dinosaur which lived during the Late Cretaceous.
Aniksosaurus is a genus of avetheropod dinosaur from what is now Chubut Province, Argentina. It lived during the Cenomanian to Turonian of the Cretaceous period, between 96-91 million years ago. The type species, Aniksosaurus darwini, was formally described from the Bajo Barreal Formation of the Golfo San Jorge Basin by Rubén Dario Martínez and Fernando Emilio Novas in 2006; the name was first coined in 1995 and reported in the literature in 1997. The specific epithet honors Charles Darwin who visited Patagonia in 1832/1833 during the Voyage of the Beagle.
The Candeleros Formation is a geologic formation that crops out in the Río Negro, Neuquén, and Mendoza provinces of northern Patagonia, Argentina. It is the oldest formation in the Neuquén Group and belongs to the Rio Limay Subgroup. Formerly that subgroup was treated as a formation, and the Candeleros Formation was known as the Candeleros Member.
Epachthosaurus was a genus of titanosaurian sauropod dinosaur from the Late Cretaceous. It was a basal lithostrotian titanosaur. Its fossils have been found in Central and Northern Patagonia in South America.
The Plottier Formation is a geologic formation that outcrops in the Argentine Patagonian provinces of Río Negro and Neuquén. It is the younger of two formations belonging to the Río Neuquén Subgroup within the Neuquén Group of the Neuquén Basin, with the oldest rocks dating from the late Coniacian and its youngest maybe from the very start of the Santonian. Formerly, that subgroup was treated as a formation, and the Plottier Formation was known as the Plottier Member.
Rinconsaurus is a genus of titanosaur sauropod dinosaur from the Late Cretaceous in what is now Argentina. The type species, Rinconsaurus caudamirus, was described by Calvo and Riga in 2003, and is based on three partial skeletons.
The Anacleto Formation is a geologic formation with outcrops in the Argentine Patagonian provinces of Mendoza, Río Negro, and Neuquén. It is the youngest formation within the Neuquén Group and belongs to the Río Colorado Subgroup. Formerly that subgroup was treated as a formation, and the Anacleto Formation was known as the Anacleto Member.
The Camarillas Formation is a geological formation in the Teruel Province of Aragón, Spain whose strata date back to the Early Cretaceous. The sandstones, mudstones and conglomerates of the formation, that due to syn-sedimentary faulting varies greatly in thickness from 300 to 800 metres, were deposited in fluvial, deltaic and lacustrine environments.
Lognkosauria is a clade of giant long-necked sauropod dinosaurs within the clade Titanosauria. It includes some of the largest and heaviest dinosaurs known. They lived in South America and likely Asia during the Late Cretaceous period.
Drusilasaura is an extinct genus of possible lognkosaurian titanosaur sauropod dinosaur which lived during the late Cretaceous of Santa Cruz Province of southern Patagonia, Argentina.
Aeolosaurini is an extinct clade of titanosaurian dinosaurs known from the Cretaceous period of Argentina and Brazil. Rodrigo M. Santucci and Antonio C. de Arruda-Campos (2011) in their cladistic analysis found Aeolosaurus, Gondwanatitan, Maxakalisaurus, Panamericansaurus and Rinconsaurus to be aeolosaurids.
Katepensaurus is an extinct genus of rebbachisaurid sauropod dinosaur known from the Late Cretaceous of south-central Chubut Province of central Patagonia, Argentina. It contains a single species, Katepensaurus goicoecheai.
Sarmientosaurus is a genus of titanosaurian sauropod dinosaur belonging to the Titanosauria. It lived in what is now South America, specifically Argentina, during the Upper Cretaceous Period about 95 million years ago. The type species is Sarmientosaurus musacchioi.
The Lago Colhué Huapí Formation is a Late Cretaceous geologic formation of the Chubut Group in the Golfo San Jorge Basin in Patagonia, Argentina. The formation, named after Lake Colhué Huapí, is overlain by the Salamanca Formation of the Río Chico Group and in some areas by the Laguna Palacios Formation.
Colhuehuapisuchus is an extinct genus of peirosaurid notosuchian known from the Late Cretaceous Lago Colhué Huapí Formation in Argentina. It contains a single species, Colhuehuapisuchus lunai. It is known from a single anterior end of a lower mandible. Its name comes from the formation its holotype was found, the Lago Colhué Huapí Formation along with the suffix -suchus, from Greek, which is often used as the suffix for crocodilians.