Sierra Bayas Group

Sierra Bayas Group
Stratigraphic range: Neoproterozoic
Type Stratigraphic group
Underlies Cerro Negro Formation
Balcarce Formation
Overlies Buenos Aires Complex
Lithology
Primary Limestone, shale (inc. argillite), quartzite, dolomite, quartz-arkose
Other Diamictite
Location
Region Buenos Aires Province
Country Argentina

Sierra Bayas Group is a sedimentary group of Neoproterozoic age in Buenos Aires Province, Argentina. The group crops out in the central and northwestern parts of the Tandilia System, a chain of hills made up by of ancient rocks. Together with the nearby Cerro Negro Formation and it is contains the oldest sedimentary formations in Argentina that have not been subject to significant metamorphism or deformation.[1] It was formerly grouped together with Cerro Negro Fromation and the Ordivician Balcarce Formation into La Tinta Group.[2] Sierra Bayas Group and the former La Tinta Group have equivalents in Southern Africa, in La Tinta Group in particular is considered equivalent to the Nama Group found in Namibia and South Africa.[1][2] From top to bottom Sierra Bayas Group is subdivided Loma Negra, Olavarría, Cerro Largo, Colombo and Villa Mónica formations.[1] Sierra Bayas Group has a thickness of 175 meters[2] and the age its rocks range from Tonian[3] to Ediacaran.[4]

See also

References

  1. 1 2 3 Arrouy, M. Julia; Poiré, Daniel G.; Gómez Peral, Lucía E.; Canalicchio, José María (2015). "Sedimentología y estratigrafía del Grupo La Providencia (nom. nov.): cubierta superior neoproterozoica, Sistema de Tandilia, Argentina". Latin American Journal of Sedimentology and Basin Analysis (in Spanish). 22 (2).
  2. 1 2 3 Bossi, Jorge; Cingolani, Carlos (2009). "Extension and general evolution of the Río de la Plata Craton" (PDF). Developments in Precambrian Geology. Elsevier.
  3. ↑ Kawashita, K.; Varela, R.; Cingolani, C.; Soliani Jr., E.; Linares, E.; Valencio, S.A.; Ramos, A.V.; Do Campo, M. (1999). Geochronology and chemostratigraphy of "La Tinta" Neoproterozoic sedimentary rocks, Buenos Aires Province, Argentina (PDF). II South American Symposium on Isotope Geology, Brazil. pp. 403–407.
  4. ↑ Pazos, P.J.; Rapalini, A. (2011). "The controversial stratigraphy of the glacial deposits in the Tandilia System, Argentina" (PDF). Geological Society, London. pp. 565–569. Missing or empty |title= (help)


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