Puncoviscana Formation | |
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Stratigraphic range: Ediacaran–Cambrian ~ | |
Type | Formation |
Underlies | Mesón Group |
Lithology | |
Primary | Shale, sandstone, conglomerate, limestone, slate, schist |
Location | |
Location | Between Río de la Plata-Pampia Craton & Arequipa Massif |
Coordinates | 24°00′S 64°00′W / 24.0°S 64.0°W |
Region | Catamarca, Jujuy, La Rioja, Salta & Tucumán Provinces Tarija Department |
Country | Argentina Bolivia |
Extent | Cordillera Oriental |
Type section | |
Named for | Puncoviscana |
Named by | Turner |
Year defined | 1960 |
Puncoviscana Formation (Spanish: Formación Puncoviscana) is a formation of sedimentary and metasedimentary rocks Late Ediacaran and Lower Cambrian age, estimated at between 700 and 535 Ma, that crop out in the Argentine Northwest. Most of the formation lies in Jujuy, Salta and Tucumán Province albeit some authors extend the formation further south to the Sierras Pampeanas near Córdoba.[1]
There are various tectonic interpretations on the origin and type of sedimentary basin that accumulated Puncoviscana Formations sediments. An early interpretation was that the sediments originated from a passive marginal basin of the ancient continent Gondwana. Others suggested an intra-cratonic rift or aulacogen basin between Río de la Plata-Pampia Craton and Arequipa Massif. Yet other hypotheses revolve around the idea that the Puncoviscana Formation is related to a terrane called Pampia that accreted to Gondwana causing the closure of a sea in the way.[1]