Lecho Formation

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Lecho Formation
Stratigraphic range: Early Maastrichtian
~70–68  Ma
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Type Geological formation
Unit of Salta Group
Underlies Yacoraite Formation
Overlies Los Blanquitos Formation
Lithology
Primary Sandstone
Location
Coordinates 26°06′S65°24′W / 26.1°S 65.4°W / -26.1; -65.4
Approximate paleocoordinates 28°36′S52°00′W / 28.6°S 52.0°W / -28.6; -52.0
Region Jujuy, Salta
CountryArgentina
Extent Salta Basin
Relief Map of Argentina.jpg
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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.

Contents

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

Aves and Dinosaurs from the Lecho Formation
GenusSpeciesLocationStratigraphic positionMaterialNotesImages
Elbretornis E. bonapartei Scapula, partial coracoid, humerus, partial radius, partial ulna [2] Enantiornithes
Enantiornis [3] E. leali [3] "Postcranial elements" [4] Enantiornithes
Lectavis [3] L. bretincola [3] "Tarsometatarsus and tibiotarsus" [4] Enantiornithes
Lectavis bretincola reconstruction by Lauren Helton.jpg
Martinavis M. minorPartial humerus [2] Enantiornithes
M. saltariensisHumerus [2]
M. vinceiHumeri [2]
M. whetstoneiPartial humerus [2]
Noasaurus [3] N. leali [3] Isolated elements from the head and foot, as well as a verebral arch. [5] A putative oviraptorosaurian cervical vertebra [6] is likely to belong to this taxon. [7] Noasaurid abelisaurs
Noasaurus leali skeletal diagram.png
Saltasaurus [3] S. loricatus [3] "Partial skeletons of at least [six] individuals, including jaws and armor." [8] Saltasaurid titanosaurs
Saltasaurus dinosaur.png
Soroavisaurus [3] S. australis [3] "Tarsometatarsus and phalanges." [9] Avisaurid enantiornithes
Yungavolucris [3] Y. brevipedalis [3] "Tarsometatarsi" [9] Enantiornithes

See also

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References

  1. Weishampel et al., 2004, "Dinosaur distribution (Late Cretaceous, South America)." pp. 600-604
  2. 1 2 3 4 5 Walker & Dyke, 2009
  3. 1 2 3 4 5 6 7 8 9 10 11 12 "63.7 Provincia de Salta, Argentina; 3. Lower Kirtland Formation," in Weishampel et al., 2004, p.603
  4. 1 2 "Table 11.1," in Weishampel et al., 2004, p.213
  5. "Table 3.1," in Weishampel et al., 2004, p.49
  6. Frankfurt & Chiappe, 1999
  7. Agnolin & Martinelli, 2007
  8. "Table 13.1," in Weishampel et al., 2004, p.270
  9. 1 2 "Table 11.1," in Weishampel et al., 2004, p.214

Bibliography