Reca Project


The Roraima province in Brazil is part of the Guiana Shield (GS), in the Maroni-Itacaiúnas province, that is mainly formed by Paleoproterozoic rocks formed during the Trans-Amazonian orogeny that resulted from convergence between the Archean nuclei of the Amazonian Craton and the West African Craton, 2.2 to 1.9 Ga ago. The GS western side, where is located the study area, exposes Paleoproterozoic sedimentary sequences, magmatic suites and tectono-metamorphic series. The study area morphology is characterized by the presence of high elevation surface, above 2 km.
Lateritic duricrust blocks come from high altitudes ranging from 835 to 950 m a.s.l in Sierra Lilas, Santo Rosa and Uiramuta sites, for the purpose of mineralogical and geochronological dating.
Credit : J.-Y. Roig