Cerro Barcino Formation
The Cerro Barcino Formation (also known as the Gorro Frigio Formation) is a geological formation in South America whose strata span the Early Cretaceous. The top age for the formation has been estimated to be Albian.[1] Earlier estimates placed the formation until the Campanian.[2]
Cerro Barcino Formation Stratigraphic range: Hauterivian-Albian ~130–100 Ma | |
---|---|
Type | Geological formation |
Unit of | Chubut Group |
Sub-units | Puesto Manuel Arce Bayo Overo Las Plumas Cerro Castaño La Paloma |
Underlies | La Colonia, Paso del Sapo & Lefipán Formations |
Overlies | Los Adobes Formation |
Lithology | |
Primary | Mudstone, sandstone |
Other | Conglomerate, tuff |
Location | |
Coordinates | 43.8°S 68.6°W |
Approximate paleocoordinates | 44.7°S 35.1°W |
Region | Chubut Province |
Country | ![]() |
Extent | Cañadón Asfalto Basin |
Type section | |
Named for | Cerro Barcino |
![]() ![]() Cerro Barcino Formation (Argentina) |
The formation was deposited in the Cañadón Asfalto Basin, a rift basin that started forming in the earliest Jurassic.[3] Dinosaur remains are among the fossils that have been recovered from the formation.[4]
The Cerro Barcino Formation is the second-youngest unit of the Chubut Group, which also includes the older Los Adobes Formation. Both formations cover a vast area in Chubut Province, Argentina. The two formations are distinguished by geological features suggesting a distinct change in climate, from a wetter, flood plain environment in the Los Adobes to a much more arid, desert-like environment in the Cerro Barcino.[2]
The Cerro Barcino Formation is subdivided into several subunits (members).[2] From oldest to youngest:
- La Paloma
- Characterized by arid plains interspersed with sand dunes
- Cerro Castaño
- A return to more humid, flood-plain conditions
- Las Plumas
- Bayo Overo
- Puesto Manuel Arce
The final three members were estimated to range from Albian to Campanian age (112 to 83 million years ago), while the La Paloma dates to the latest Hauterivian (130 Ma).[2]
Fossil content
Indeterminate abelisaurid remains.[4] Possible indeterminate carcharodontosaurid remains.[4] Indeterminate Titanosauria remains.[4] Also, an unnamed titanosauriform.[4]
Crurotarsans
Crocodylomorphs | ||||||
---|---|---|---|---|---|---|
Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
Barcinosuchus | B. gradilis | Near El Escorial village, Chubut Province | Cerro Castaño Member | "Skull, mandible, and postcranial remains." | A peirosaurid. The first crocodyliform from the Chubut Group[5] | |
Dinosaurs
Dinosaurs | |||||
---|---|---|---|---|---|
Genus | Species | Member | Material | Notes | Images |
Chubutisaurus | C. insignis | Bayo Overo | "[Two] partial skeletons including most limb elements and caudal vertebrae."[6] | A titanosaur[4] | ![]() |
Genyodectes | G. serus | Cerro Castaño[7] | "Premaxillae, partial dentaries"[8] | A possible ceratosaurid | ![]() |
Patagotitan | P. mayorum | ![]() | |||
Tyrannotitan | T. chubutensis | Cerro Castaño | A carcharodontosaurid[9] | ![]() | |
"Megalosaurus" | "Megalosaurus" inexpectatus | Indeterminate remains originally described as a species of Megalosaurus[4] | |||
See also
- List of dinosaur-bearing rock formations
- La Amarga Formation, contemporaneous fossiliferous formation of the Neuquén Basin
- Lohan Cura Formation, contemporaneous fossiliferous formation of the Neuquén Basin
- Río Belgrano Formation, contemporaneous fossiliferous formation of the Austral Basin
References
- Figari et al., 2015, p.153
- Rauhut et al., 2003
- Figari et al., 2015, p.142
- Weishampel et al., 2004, pp.563-570
- Leardi & Pol, 2009
- "Table 13.1," in Weishampel et al., 2004, p.268
- Rauhut, 2004
- "Table 3.1," in Weishampel et al., 2004, p.50
- Novas et al., 2005
Bibliography
- Figari, Eduardo G.; Roberto A. Scasso; Rubén N. Cúneo, and Ignacio Escapa. 2015. Estratigrafía y evolución geológica de la Cuenca de Cañadón Asfalto, Provincia del Chubut, Argentina. Latin American Journal of Sedimentology and Basin Analysis 22. 135–169. Accessed 2018-09-10.
- Leardi, Juan Martín, and Diego Pol. 2009. The first crocodyliform from the Chubut Group (Chubut Province, Argentina) and its phylogenetic position within basal Mesoeucrocodylia. Cretaceous Research 30. 1376–1386. Accessed 2019-04-06.doi:10.1016/j.cretres.2009.08.002
- Novas, F.E.; S. De Valais; P. Vickers-Rich, and T. Rich. 2005. A large Cretaceous theropod from Patagonia, Argentina, and the evolution of carcharodontosaurids. Naturwissenschaften 92. 226–230. Accessed 2019-04-06.doi:10.1007/s00114-005-0623-3PMID 15834691Bibcode: 2005NW.....92..226N
- Rauhut, O.W.M. 2004. Provenance and anatomy of Genyodectes serus, a large-toothed ceratosaur (Dinosauria: Theropoda) from Patagonia. Journal of Vertebrate Paleontology 24. 894–902. Accessed 2019-04-06.
- Rauhut, O.W.M.; G. Cladera; P. Vickers-Rich, and T.H. Rich. 2003. Dinosaur remains from the Lower Cretaceous of the Chubut Group, Argentina. Cretaceous Research 24. 487–497. Accessed 2019-04-06.doi:10.1016/S0195-6671(03)00067-3
- Weishampel, David B.; Peter Dodson, and Halszka Osmólska (eds.). 2004. The Dinosauria, 2nd edition, 1–880. Berkeley: University of California Press. Accessed 2019-02-21.ISBN 0-520-24209-2