Puncoviscana Formation

Puncoviscana Formation Stratigraphic range: Ediacaran–Cambrian
Type	Formation
Underlies	Mesón Group
Lithology
Primary	Shale, sandstone, conglomerate, limestone, slate, schist
Location
Country	Argentina, Bolivia

Puncoviscana Formation (Spanish: Formación Puncoviscana) is a formation of sedimentary and metasedimentary rocks Late Ediacaran and Lower Cambrian age 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.

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. Other hypotheses revolved 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.

The formation includes rocks such as shales, sandstones, conglomerates, limestones, slates and schists. Stratigraphically, the upper boundary of the Puncoviscana Formation is the Tilcarian unconformity, which is overlain by Cambrian and Ordovician sedimentary rocks of the Mesón Group that extend across the Argentine Northwest and Bolivia.