The Paleozoic Aquidauana Formation occurs in the northwest of the Paraná Basin and is generally correlated to the Itararé Group (Visean to Gzhelian–Asselian). Although it exhibits some glacial features, its red color makes it difficult to position it accurately within the basin's stratigraphic column. Paleomagnetic work has been carried out on 50 sites of the Aquidauana Formation comprising several lithotypes and extending on a nearly north-south strip covering about 5° in latitude. The magnetic mineralogy investigation identified hematite as the main remanence carrier, followed by magnetite. Thermal cleaning up to 700 °C revealed that both minerals carry the same magnetic components. Two independent groups of remanences were recognized, allowing the calculation of a paleomagnetic pole for Group A that matches other Moscovian poles for Western Gondwana and is slightly older than the Rio do Sul Formation of the Paraná Basin. The other paleomagnetic pole (Group B) plots close to the Permo-Triassic Araguainha pole, based on impact-melt rocks from the impact crater, suggesting remagnetization. • Paleomagnetic work on 50 sites of the Paleozoic Aquidauana Formation, northwest of the Paraná Basin, allowed the calculation of a paleomagnetic pole of Moscovian age. • This pole plots close to the Moscovian Rio do Sul Formation pole, the top of the Itararé Group, but its mixed polarity permits a differentiation from the only-reversed polarity of the Rio do Sul pole. • The paleomagnetic data allowed a definite positioning of the Aquidauana Formation within the Itararé Group, as its red layers are distinct from the other glacial formations of the Group.
Ernesto et al. (Sun,) studied this question.