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.Casal et al., 2016, p.55 The sandstones, claystones, mudstones, conglomerates and tuff were deposited in a fluvial environment.Bajo Barreal Formation at Fossilworks.org 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.Sywan, 2001, p.131
Fossil content
Dinosaurs Indeterminate abelisauroids and titanosaurs have been recovered from the formation.
Ornithischia Ornithischians of the Bajo Barreal FormationGenusSpeciesLocationStratigraphic positionMaterialNotesImage Notohypsilophodon N. comodorensis Lower "Vertebrae, partial fore- and hindlimb""Table 18.1," in Weishampel, et al. (2004). Page 395. An elasmarian ornithopod
Sauropods Sauropods of the Bajo Barreal FormationGenusSpeciesLocationStratigraphic positionMaterialNotesImage Andesaurus A. sp. Lower A titanosaurian sauropod CampylodoniscusHaubold, H. & Kuhn, O., 1961, Lebensbilder und Evolution fossiler Saurier, Amphibien und Reptilien, Wittenberg : Ziemsen C. ameghinoi Lower Maxilla with seven teeth.Huene, F. von, 1929, "Los Saurisquios y Ornitisquios del Cretaceo Argentino", Anales del Museo de La Plata, 3(2): 82-83 A titanosaurian sauropod DrusilasauraCésar Navarrete, Gabriel Casal and Rubén Martínez (2011). "Drusilasaura deseadensis gen. et sp. nov., a new titanosaur (Dinosauria-Sauropoda), of the Bajo Barreal Formation, Upper Cretaceous of north of Santa Cruz, Argentina". Revista Brasileira de Paleontologia 14 (1): 1-14. . D. deseadensis Upper "four dorsal vertebrae, one sacral vertebra, six caudal vertebrae, left scapula, dorsal rib fragments, two haemapophyses and indeterminate fragments" A colossosaurian titanosaur Elaltitan E. lilloi Lower A partial skeleton A lithostrotian titanosaur Epachthosaurus E. sciuttoi Lower "Vertebrae [and] partial illium.""Table 13.1," in Weishampel, et al. (2004). Page 268. A titanosaurian sauropod Katepensaurus K. goicoecheai Lower Partial skeleton A rebbachisaurid Rebbachisauridae Indet. Indeterminate Lower Dorsal vertebra Different from Katepensaurus. SarmientosaurusMartínez et al., 2016 S. musacchioi Lower A skull A diamantinasaurian sauropod
Theropods Theropods of the Bajo Barreal FormationGenusSpeciesLocationStratigraphic positionMaterialNotesImage Abelisauridae Indet. Indeterminate Lower UNPSJB-PV247 A nearly complete left maxilla Possibly distinct from Xenotarsosaurus. Estimated to be long, larger than Xenotarsosaurus. Abelisauridae Indet. Indeterminate Lower partial skeleton Different from all other comparable abelisaurids, but can't be compared with Xenotarsosaurus. Aniksosaurus"63.2 Provincia de Chubut, Argentina; 2. Bajo Barreal Formation," in Weishampel, et al. (2004). Page 602. A. darwini Lower A basal coelurosaur Megaraptoridae Indet. Indeterminate Upper part of lower Lowermost part of upper Two partial skeletons Xenotarsosaurus X. bonapartei Lower A vertebra and a nearly complete hind limb"Table 3.1," in Weishampel, et al. (2004). Page 49. A brachyrostran abelisaurid
Other fossils Other fossils found in the formation include:Casal, 2016, p.58Estancia Laguna Palacios "2005 Quarry" at Fossilworks.org6 km north of Estancia "Ocho Hermanos" at Fossilworks.org
Bonapartemys bajobarrealis Prochelidella argentinae Anura indet. Chelonia indet. Crocodylia indet. Pterosauria indet.
See also List of dinosaur-bearing rock formations Mata Amarilla Formation, contemporaneous formation of the Austral Basin Lisandro Formation, contemporaneous formation of the Neuquén Basin
References
Bibliography
Further reading G. Casal and L. Ibiricu. 2010. Materiales asignables a Epachthosaurus Powell, 1990 (Sauropoda: Titanosauria), de la Formación Bajo Barreal, Cretácico Superior, Chubut, Argentina [Materials assignable to Epachthosaurus Powell, 1990 (Sauropoda: Titanosauria), from the Bajo Barreal Formation, Upper Cretaceous, Chubut, Argentina]. Revista Brasileira de Paleontologia 13(3):247-256 L. M. Ibiricu, G. A. Casal, R. D. Martinez, M. C. Lamanna, M. Luna and L. Salgado. 2013. Katepensaurus goicoecheai, gen. et sp. nov., a Late Cretaceous rebbachisaurid (Sauropoda, Diplodocoidea) from central Patagonia, Argentina. Journal of Vertebrate Paleontology 33(6):1351-1366 L. M. Ibiricu, G. A. Casal, M. C. Lamanna, R. D. Martínez, J. D. Harris and K. J. Lacovara. 2012. The southernmost records of Rebbachisauridae (Sauropoda: Diplodocoidea), from early Late Cretaceous deposits in central Patagonia. Cretaceous Research 34:220-232 R. D. Martínez, F. E. Novas, and A. Ambrosio. 2004. Abelisaurid remains (Theropoda, Ceratosauria) from southern Patagonia. Actas I del Congreso Ltinoamericano de Paleontología de Vertebrados. Ameghiniana 41(4):577-585 R. D. Martínez and F. E. Novas. 1997. Un nuevo tetanuro (Dinosauria: Theropoda) de la Formación Bajo Barreal (Cretácico Superior), Patagonia [A new tetanuran (Dinosauria: Theropoda) from the Bajo Barreal Formation (Upper Cretaceous), Patagonia]. Ameghiniana 34(4):538 R. D. Martínez, A. Maure, M. Oliva and M. Luna. 1993. Un maxilar de Theropoda (Abelisauria) de la Formación Bajo Barreal, Cretacico Tardio, Chubut, Argentina [A theropod (Abelisauria) maxilla from the Bajo Barreal Formation, Late Cretaceous, Chubut, Argentina]. Ameghiniana 30(1):109-110 J. C. Sciutto and R. D. Martínez. 1994. Un nuevo yacimiento fosilífero de la Formación Bajo Barreal (Cretacico Tardio) y su fauna de saurópodos [A new fossiliferous locality in the Bajo Barreal Formation (Late Cretaceous) and its sauropod fauna]. Naturalia Patagonica, Ciencias de la Tierra 2:27-47