Cerro Negro Formation

Cerro Negro Formation Stratigraphic range: Ediacaran
Type	Formation
Underlies	Balcarce Formation
Overlies	Sierra Bayas Group
Lithology
Primary	Shale, sandstone
Other	Marl
Location
Region	Buenos Aires Province
Country	Argentina

Cerro Negro Group 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.

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