The Carajás Province has been the target of several studies that seek to understand its current configuration. The purpose of this work is no different, and aims at the individualization of TTG affinity granitoids, initially inserted in the geological context of the Xingu Complex, based on the elaboration of a semi-detail scale geological map of an area located in the north of the Tucumã and Ourilândia cities, in the center-west portion of the province. The data obtained during geological mapping, combined with petrographic studies and modal analysis data, allowed identifying the occurrence of three types of granitoids: ±amphibole-biotite-tonalite, biotite-trondhjemite and biotite-granodiorite. The structural aspects of the outcropping area of these granitoids coincide with the regional trend, which is predominantly NE-SW with inflections towards E-W, as a result of the installation of shear zones in the Itacaiúnas Belt. The magmatic epidote is a very frequent accessory mineral in these rocks, especially in the amphibole-bearing tonalite variety, followed by zircon, allanite and opaque minerals. These granitoids still preserve the original hypidiomorphic granular texture and some deformational aspects that indicate that these rocks reached deformation temperatures above 600°C, such as bulging features (BLG) until the reduction of the grain boundary area (GBAR). In general, such granitoids show compositional and textural affinities with other important lithologies already studied in the province: Arco Verde, Mariazinha, São Carlos and Caracol tonalites, Mogno and Água Fria trondhjemites, and the TTGs from Água Azul do Norte. In addition, geochronological data available in the literature indicate that the studied rocks represent the TTG magmatism that occurred between 2.97 and 3.0 Ga, and that their evidence of migmatization (metamorphism of the amphibolite facies) suggest that this portion of the province represents the westward extension of what had been defined for the Sapucaia Terrain.
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