Yacoraite Formation

Yacoraite Formation
Stratigraphic range: Maastrichtian-Danian
Type	Geological formation
Unit of	Salta Group
Sub-units	Amblayo, Güemes, Alemanía & Juramento Members
Underlies	Mealla, Olmedo & Tunal Formations
Overlies	Lecho Formation
Lithology
Primary	Sandstone
Other	Limestone
Location
Coordinates	23.5°S 65.4°W / -23.5; -65.4
Approximate paleocoordinates	26.1°S 51.9°W / -26.1; -51.9
Region	Jujuy & Salta Provinces
Country	Argentina
Extent	Salta Basin
Type section
Named for	Yacoraite village, Tilcara Department
Yacoraite Formation (Argentina)

The Yacoraite Formation is a largely Mesozoic geologic formation. The deposits of this formation mainly date from the Maastrichtian of the Upper Cretaceous, but the Cretaceous–Paleogene boundary (K–T boundary) runs right through this formation near its top, and the uppermost parts are consequently from the Danian (Lower Paleocene). It was probably deposited around the intertidal zone, as the sedimentary rocks of this formation alternate according to sea level changes between deposits of muddy beaches and of shallow ocean.

Fossil content

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

Well-preserved dinosaur footprints assigned to Hadrosaurichnus australis have been found in this formation, as were fossil eggs, stromatolites and the Mesozoic palynomorph Aquilapollenites. 

Other fossils recovered from the formation are:

• Pucapristis branisi
• Gasteroclupea branisai
• Coelodus toncoensis
• Dolichochampsa minima

Ichnofossils

• Hadrosaurichnus australis
• Salfitichnus mentoor
• Taponichnus donottoi
• Telosichnus saltensis
• Yacoraitichnus avis

See also

• List of dinosaur-bearing rock formations
  • List of stratigraphic units with indeterminate dinosaur fossils

References

Bibliography

• Leonardi, Giuseppe (1994), Annotated Atlas of South America Tetrapod Footprints (Devonian to Holocene) with an appendix on Mexico and Central America, Ministerio de Minas e Energia - Companhia de Pesquisa de Recursos Minerais, Geological Service of Brazil, pp. 1–248, retrieved 2019-03-25
• Marquillas, Rosa; del Papa, Cecilia; Sabino, Ignacio; Heredia, Jorge (2003), "Prospección del límite K/T en la cuenca del Noroeste, Argentina - The K/T boundary prospecting in the Northwest Basin, Argentina", Revista de la Asociación Geológica Argentina, 58: 271–274, retrieved 2019-03-25
• Weishampel, David B.; Dodson, Peter; Osmólska, Halszka (2004), The Dinosauria, 2nd edition, Berkeley: University of California Press, pp. 880 p, ISBN 0-520-24209-2, retrieved 2019-02-21