Pre-Pampean metasedimentary rocks from the Argentinian Puna: Evidence for the Ediacaran margin of Gondwana or the Arequipa-Antofalla-Western Pampeanas block

The most likely interpretation is that these successions predate the Pampean orogeny and deposition of the Cambrian Puncoviscana Formation. Consequently, the rocks could either have been deposited within the (passive) margin of the Arequipa-Antofalla-Western Pampeanas terrane (western Gondwana) or MARA block; or are unusual, reworked sedimentary rocks related to the active continental margin of the Pampean orogen.