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Lecho Formation

Coordinates: 26°06′S 65°24′W / 26.1°S 65.4°W / -26.1; -65.4
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Lecho Formation
Stratigraphic range: Early Maastrichtian
~70–68 Ma
TypeGeological formation
Unit ofSalta Group
UnderliesYacoraite Formation
OverliesLos Blanquitos Formation
Lithology
PrimarySandstone
Location
Coordinates26°06′S 65°24′W / 26.1°S 65.4°W / -26.1; -65.4
Approximate paleocoordinates28°36′S 52°00′W / 28.6°S 52.0°W / -28.6; -52.0
RegionJujuy, Salta
CountryArgentina
ExtentSalta Basin
Lecho Formation is located in Argentina
Lecho Formation
Lecho Formation (Argentina)

The Lecho Formation is a geological formation in the Salta Basin of the provinces Jujuy and Salta of northwestern Argentina. Its strata date back to the Early Maastrichtian, and is a unit of the Salta Group. The fine-grained bioturbated sandstones of the formation were deposited in a fluvial to lacustrine coastal plain environment.

Dinosaur remains are among the fossils that have been recovered from the formation.[1]

According to Frankfurt and Chiappe (1999), the Lecho Formation is composed of reddish sandstones. The Lecho is part of the Upper/Late Cretaceous Balbuena Subgroup (Salta Group), which is a near-border stratigraphic unit of the Andean sedimentary basin. Fossils from this formation include the titanosaur Saltasaurus along with a variety of avian and non-avian theropods.

Fossil content

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Dinosaurs

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Dinosaurs from the Lecho Formation
Genus Species Location Material Notes Images
Abelisauridae[2] Indeterminate El Brete Isolated teeth. May represent more than one species of abelisaurid
Elbretornis[3] E. bonapartei El Brete Scapula, partial coracoid, humerus, partial radius, partial ulna An enantiornithine bird
Enantiornis[3][4] E. leali El Brete Postcranial elements An enantiornithine bird
Euenantiornithes indet.[3] Indeterminate El Brete Partial right lower jaw An enantiornithine bird
Lectavis[5] L. bretincola El Brete Tarsometatarsus and tibiotarsus An enantiornithine bird
Martinavis[3] M. minor El Brete Partial humerus An enantiornithine bird
M. saltariensis El Brete Humerus
M. vincei El Brete Humeri
M. whetstonei El Brete Partial humerus
Noasaurus[2] N. leali El Brete Isolated elements from the head and foot, as well as a verebral arch. A Noasaurid abelisaur
Saltasaurus[6] S. loricatus El Brete "Partial skeletons of at least [six] individuals, including jaws and armor."[7] A saltasaurid titanosaur
Soroavisaurus[5] S. australis El Brete Tarsometatarsus and phalanges. An enantiornithine bird
Yungavolucris[5] Y. brevipedalis El Brete Tarsometatarsi An enantiornithine bird

See also

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References

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  1. ^ Weishampel et al., 2004, "Dinosaur distribution (Late Cretaceous, South America)." pp. 600-604
  2. ^ a b Hendrickx, Christophe; Cerroni, Mauricio A; Agnolín, Federico L; Catalano, Santiago; Ribeiro, Cátia F; Delcourt, Rafael (2024-12-01). "Osteology, relationship, and feeding ecology of the theropod dinosaur Noasaurus leali, from the Late Cretaceous of North-Western Argentina". Zoological Journal of the Linnean Society. 202 (4). doi:10.1093/zoolinnean/zlae150. ISSN 0024-4082.
  3. ^ a b c d Cyril A. Walker; Gareth J. Dyke (2009). "Euenantiornithine birds from the Late Cretaceous of El Brete (Argentina)" (PDF). Irish Journal of Earth Sciences. 27: 15–62. doi:10.3318/IJES.2010.27.15. S2CID 129573066. Archived from the original (PDF) on 2012-03-20.
  4. ^ Walker, C. A. (1981). "New subclass of birds from the Cretaceous of South America". Nature. 292 (5818): 51–53. doi:10.1038/292051a0. ISSN 0028-0836.
  5. ^ a b c Chiappe, Luis (1993). "Enantiornithine (Aves) tarsometatarsi from the Cretaceous Lecho Formation of northwestern Argentina". American Museum Novitates (3083): 1–27. S2CID 39613970.
  6. ^ Zurriaguz, Virginia; Powell, Jaime (2015-05-01). "New contributions to the presacral osteology of Saltasaurus loricatus (Sauropoda, Titanosauria) from the Upper Cretaceous of northern Argentina". Cretaceous Research. 54: 283–300. doi:10.1016/j.cretres.2014.12.012. ISSN 0195-6671.
  7. ^ "Table 13.1," in Weishampel et al., 2004, p.270

Bibliography

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