Huayquerías Formation

The Huayquerías Formation (Spanish: Formación Huayquerías) is a Late Miocene fossiliferous geological formation of the Frontal Cordillera and Cuyo Basin of Argentina. The formation crops out in the central Mendoza Province.

Huayquerías Formation
Stratigraphic range: Messinian-Zanclean
(defined as Huayquerian)
~6.5–5 Ma
TypeGeological formation
UnderliesTunuyán Formation
ThicknessUp to 126 m (413 ft)
Lithology
PrimaryMudstone
OtherSandstone, tuff
Location
Coordinates33°48′S 69°00′W / 33.8°S 69.0°W / -33.8; -69.0
Approximate paleocoordinates34°00′N 66°54′W / 34.0°N 66.9°W / 34.0; -66.9
RegionMendoza Province
CountryArgentina
ExtentFrontal Cordillera & Cuyo Basin
Type section
Named byKraglievitch
Year defined1934
RegionMendoza Province
CountryArgentina
Huayquerías Formation is located in Argentina
Huayquerías Formation
Huayquerías Formation (Argentina)

The formation, with a maximum thickness of 126 metres (413 ft), comprises reddish mudstones with thin beds of tuffs and sandstones, deposited in a fluvial, environment. The tuff in the formation is dated to 5.84 ± 0.41 Ma, placing it in the Huayquerian SALMA, the age named after the formation by Kraglievitch in 1934.

The formation has provided fossils of the procyonid Cyonasua pascuali and the litoptern Huayqueriana cristata, named after the formation.

Description edit

The Huayqueriás Formation, present in the Frontal Cordillera and the neighboring Cuyo Basin, was described in 1934 by Kraglievitch as the basis for the Huayquerian South American land mammal age. The name Huayquerías means "badlands".[1] The formation comprises reddish mudstones with mudcracks, paleoburrows and ichnofossils of vertebrates. Thin sandstone layers of up to 12 centimetres (4.7 in) thick exist in the formation. An ashfall bed exists at 83 metres (272 ft) below the contact with the slightly angular unconformably[2] overlying Tunuyán Formation in a total section of 126 metres (413 ft).[3] The tuff has been dated using 40K/40Ar analysis to 5.84 ± 0.41 Ma.[4]

Paleontological significance edit

The Huayquerías Formation has been used to define the Huayquerian South American land mammal age, ranging from 9.0 to 6.8 Ma. However, later analysis of the ashfall bed in the formation, provided a much younger age of 5.84 ± 0.41 Ma, extending the temporal range of the Huayquerian SALMAans until near the Miocene-Pliocene limit. The Huayqueriás Formation has provided fossils of Cyonasua pascuali,[5] and the litoptern Huayqueriana cristata, the latter of which, named after the formation.[1]

See also edit

References edit

  1. ^ a b Forasiepi et al., 2016, p.1
  2. ^ Yrigoyen, 1993
  3. ^ Garrido et al, 2017, p.51
  4. ^ Marshall et al., 1986
  5. ^ Linares, 1981, p.118

Bibliography edit

Geology
Paleontology