Cerro Negro Formation, Argentina

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Cerro Negro Formation
Stratigraphic range: Ediacaran
<565  Ma
O
S
D
C
P
T
J
K
Pg
N
Type Formation
Unit of La Providencia Group
  Tandilia System
Underlies Balcarce Formation
Overlies Sierra Bayas Group
Thickness>150 m (490 ft)
Lithology
Primary Shale, sandstone
Other Marl
Location
Coordinates 37°12′04.3″S60°20′48.1″W / 37.201194°S 60.346694°W / -37.201194; -60.346694
Region Buenos Aires Province
CountryArgentina
Extent Río de la Plata Craton
Relief Map of Argentina.jpg
Gold pog.svg
Cerro Negro Formation, Argentina (Argentina)

The Cerro Negro Formation is a sedimentary formation of Ediacaran age in Buenos Aires Province, Argentina. The formation crops out along the Tandilia System, a chain of hills made up by of ancient rocks. Together with the formations of the underlying Sierra Bayas Group it is contains the oldest sedimentary formations in Argentina that have not been subject to significant metamorphism or deformation. In 2015 a complete revision of the formation was proposed. [1]

Contents

Fossil content

Soft-bodied discoidal specimens resembling Aspidella are described from the formation, that has been estimated as not older than 565 Ma. [2]

See also

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References

  1. Arrouy et al., 2015
  2. Arrouy, 2016

Bibliography