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Part of the pegmatite dykes of the Pampean Pegmatite Province formed during the orogeny. These dykes are thought to be derived from S-type granite.
The eastern magmatic belt of the Pampean orogeny is interpreted as the remains of a volcanic arc associated with an east-dipping subduction while the western one is thought to represent a younger volcanic arc that developed on what was once the accretionary prism of the orogen.
There have been differing views among geologists on the tectonic and paleogeographic position of the Puncoviscana Basin in relation to the events of the Pampean orogeny. The Pampean orogeny is believed by some geologists to be associated with the accretion of a "Pampia" to the Río de la Plata Craton, resulting from the closure of a sea that existed in-between. This sea would have been the Puncoviscana Basin. Víctor Ramos proposes instead that the Puncoviscana Basin was a foreland basin located west of a "Pampia block" that collided with Río de la Plata Craton. Contrasting to this view Aceñolaza and Toselli claim instead that the Puncoviscana Basin originated from an aulacogen splitting Arequipa-Antofalla Craton from Río de la Plata and Amazonian craton. Following this interpretation the aulacogen would have closed during the Pampean orogeny.
Tectonic interpretation
The Pampean orogeny can be considered part of the larger Terra Australis orogeny or of the Brasiliano orogeny. The Pampean orogeny developed at a similar time as the Paraguai Belt of the Brasiliano Orogeny, but in difference to the Paraguay Belt that ended up in the interior of Gondwana the Pampean Orogen remained at a continental margin. The orogen eventually ceased activity and was succeeded by the Famatinian orogeny further west.
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