Chorrillo Formation

The Chorrillo Formation, also named as Chorillo Formation,[1] is a Maastrichtian geologic formation in southern Patagonia, Argentina. The formation is more than 50 metres (160 ft) thick and underlies the Calafate Formation and rests on top of the La Irene Formation.[2]

Chorrillo Formation Stratigraphic range: Maastrichtian PreꞒ Ꞓ O S D C P T J K Pg N
Type	Geological formation
Underlies	Calafate Formation
Overlies	La Irene Formation
Thickness	>50 m (160 ft)
Lithology
Primary	Claystone
Location
Location	Patagonia
Coordinates	49.9°S 72.5°W
Approximate paleocoordinates	51.8°S 62.2°W
Region	Santa Cruz Province
Country	Argentina
Extent	Southeast of Viedma Lake North of Argentino Lake Austral Basin
Type section
Named by	Arbe & Hechem
Year defined	1984
Chorrillo Formation (Argentina)

Fossils

Dinosaur remains are among the fossils that have been recovered from the formation.

Fossils recovered from the formation are:

• Dinosaurs

  • Isasicursor
  • Nullotitan
  • Kookne
  • Megaraptoridae indet.
  • Noasauridae indet.
  • Unenlagiidae indet.

  Anurans

  • Anura indet.
  • Calyptocephalellidae indet

  Fishes

  • Teleostei indet.
  • Vidalamiinae indet.

  Mammals

  • Magallanodon
  • Mammalia indet.

  Mosasaurs

  • Mosasauridae indet.

  Snakes

  • Rionegrophis
  • Serpentes indet.

  Turtles

  • Chelidae indet.

Other fossils recovered from the formation are:

Gastropods

• Pomacea sp.
• Pleuroceridae indet.
• Potamolithus sp.
• Physa sp.
• Stenophysa sp.
• Achatinidae indet.
• Holospira sp.
• Bulimulidae indet.

See also

• List of dinosaur-bearing rock formations

References

1. Río Leona at Fossilworks.org
2. Marenssi et al., 2003, p.406

Bibliography

• Marenssi, Sergio A.; Silvio Casadío, and Sergio N. Santillana. 2003. Estratigrafía y sedimentología de las unidades del Cretácico superior-Paleógeno aflorantes en la margen sureste del lago Viedma, provincia de Santa Cruz, Argentina. Revista de la Asociación Geológica Argentina 58. 403–416. Accessed 2018-08-30.
• 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
• Novas, F.; Agnolin, F.; Rozadilla, S.; Aranciaga-Rolando, A.; Brissón-Eli, F.; Motta, M.; Cerroni, M.; Ezcurra, M.; Martinelli, A.; D'Angelo, J.; Álvarez-Herrera, J.; Gentil, A.; Bogan, S.; Chimento, N.; García-Marsà, J.; Lo Coco, G.; Miquel, S.; Brito, F.; Vera, E.; Loinaze, V.; Fernandez, M.; Salgado, L. (2019). "Paleontological discoveries in the Chorrillo Formation (upper Campanian-lower Maastrichtian, Upper Cretaceous), Santa Cruz Province, Patagonia, Argentina". Revista del Museo Argentino de Ciencias Naturales. 21 (2): 217–293. Retrieved 2021-01-05.
• Chimento, N.; Agnolin, F.; Tsuihiji, T.; Manabe, M.; Novas, F. (2020). "New record of a Mesozoic gondwanatherian mammaliaform from Southern Patagonia". The Science of Nature. Retrieved 2021-01-05.

Further reading

• J. E. Powell. 2003. Revision of South American titanosaurid dinosaurs: palaeobiological, palaeobiogeographical and phylogenetic aspects. Records of the Queen Victoria Museum Launceston 111:1-173