During Paleoproterozoic (1.98 to 1.78 Ga) anorogenic plutonism AMGC type designated by the event Uatuma covers a vast area of northern Amazonian craton. Locally, the event has received other names, such as Surumu, Iriri, Sobreiro and Colider, exposed in the states of Roraima (Group Surumu), Para (Group Iriri, Sobreiro) and Mato Grosso (Group Iriri and Intrusive Suite Colider). Surumu Group (1.98-1.96 Ga) and Colider Suite (1.78 Ga) have been the target of paleomagnetic studies, with very important results for the geodynamic evolution of the Amazonian Craton. In this project, we intend to continue paleomagnetic study of rocks of the Iriri and Sobreiro units with age of 1.88 Ga. The sampling conducted for paleomagnetic study will also be used to study the petrology of volcanic rocks formed in the late Paleoproterozoic. In addition to the characterization of the magnetic mineralogy and textures, we intend to make the chemical analysis of major mineral phases using the electron microprobe. We also aim to make the analysis of major elements and trace elements of whole rock for a group of representative samples. These analyzes will be performed during the "sandwich" doctorate at the University Paul Sabatier (Toulouse, France), under the supervision of Prof. Anne Nedelec (co-director). The data obtained in this project will allow us to characterize these volcanics geochemically to connect to their plutonic origin. In addition, we will test geodynamic models proposed for the craton, placing this unit in global paleogeographic reconstructions, and thus test the configurations proposed for the Columbia supercontinent, in addition to establish the apparent polar wander path for the Amazonian Craton between 1, 97 and 1.78 Ga. Four field sampling target areas are planned with the participation of geologists with experience in geological mapping of the respective areas.
News published in Agência FAPESP Newsletter about the scholarship: