Cerro Barcino Formation

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Cerro Barcino Formation
Stratigraphic range: HauterivianCampanian
Type Geological formation
Unit of Chubut Group
Sub-units Puesto Manuel Arce
Bayo Overo
Las Plumas
Cerro Castaño
La Paloma
Underlies La Colonia Formation, Paso de Sapo Formation, Lefipan Formation
Overlies Los Adobes Formation
Location
Region Chubut Province
Country  Argentina

The Cerro Barcino Formation (also known as the Gorro Frigio Formation) is a geological formation in South America whose strata span the mid-late Cretaceous period. Dinosaur remains are among the fossils that have been recovered from the formation.[1]

The Cerro Barcino Formation is the upper 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 are likely Albian to Campanian in age (112 to 83 million years ago), while the La Paloma may date to the latest Hauterivian (130ma).[2]

Fauna[edit]

Indeterminate abelisaurid remains.[1] Possible indeterminate carcharodontosaurid remains.[1] Indeterminate Titanosauria remains.[1] Also, an unnamed titanosauriform.[1]

Crurotarsans[edit]

Color key
Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.
Crocodylomorphs of the Adamantina Formation
Genus Species Location Stratigraphic position Material Notes Images

Barcinosuchus[3]

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.

Dinosaurs[edit]

Dinosaurs of the Cerro Barcino Formation
Genus Species Presence Material Notes Images

Chubutisaurus

Chubutisaurus insignis

Present in the Bayo Overo Member.[citation needed]

"[Two] partial skeletons including most limb elements and caudal vertebrae."[4]

A titanosaur.[1]

Genyodectes

Genyodectes serus

Present in the Cerro Castaño Member.[5]

"Premaxillae, partial dentaries."[6]

A possible ceratosaurid.

"Megalosaurus"

"Megalosaurus" inexpectatus

Indeterminate remains originally described as a species of Megalosaurus.[1]

Patagotitan

Patagotitan mayorum

Tyrannotitan

Tyrannotitan chubutensis

Present in the Cerro Castaño Member.

A carcharodontosaurid.[7]

See also[edit]

References[edit]

  1. ^ a b c d e f g Weishampel, David B; et al. (2004). "Dinosaur distribution (Early Cretaceous, South America)." In: Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. Pp. 563-570. ISBN 0-520-24209-2.
  2. ^ a b c Rauhut, O.W.M., Cladera, G., Vickers-Rich, P. and Rich, T.H. (2003). "Dinosaur remains from the Lower Cretaceous of the Chubut Group, Argentina." Cretaceous Research, 24(5): 487-497. doi:10.1016/S0195-6671(03)00067-3
  3. ^ Juan Martín Leardi and Diego Pol (2009). "The first crocodyliform from the Chubut Group (Chubut Province, Argentina) and its phylogenetic position within basal Mesoeucrocodylia". Cretaceous Research. 30 (6): 1376–1386. doi:10.1016/j.cretres.2009.08.002. 
  4. ^ "Table 13.1," in Weishampel, et al. (2004). Page 268.
  5. ^ Rauhut, O.W.M. (2004). Provenance and anatomy of Genyodectes serus, a large-toothed ceratosaur (Dinosauria: Theropoda) from Patagonia. Journal of Vertebrate Paleontology 24(4):894-902.
  6. ^ "Table 3.1," in Weishampel, et al. (2004). Page 50.
  7. ^ Novas, F. E.; S. de Valais; P. Vickers-Rich; T. Rich (2005). "A large Cretaceous theropod from Patagonia, Argentina, and the evolution of carcharodontosaurids". Naturwissenschaften. 92 (5): 226–230. Bibcode:2005NW.....92..226N. doi:10.1007/s00114-005-0623-3. PMID 15834691.