The basement rocks in the south segment of the Araguaia Belt, due to the scarcity of geochronological information, were firstly considered as of Archean age. This interpretation began to be reviewed after the geochronological investigations were carried out during the last decade, which showed an important contribution of geological processes of the Paleoproterozoic in the formation of those basement rocks. In this work an isotopic study was carried out on the basement sequences of the southern segments of the Araguaia Belt and its results were based on the single zircon Pb-evaporation technique (Pb-Pb in zircon) and the Sm-Nd (whole rock) systematic. These techniques were used in order to improve and reconstruct the geological evolution of this crustal segment where Rio do Coco Group, Rio dos Mangues Complex, and Serrote Granite occur, as well as Monte Santo Suite that also appear in this context. The geological processes identified for the region took place from the Archean through the Neoproterozoic Era. The first evidences from the archean source were obtained in some restricted orthoderivated bodies in the east sector of the mapped area in which the TDM ages varied between 3.25 and 2.78 Ga. In a clear way, the Archean occurs in the northwest portion of the studied area being represented by a metabasic rock belonged to the Rio do Coco Group (greenstone belt sequence), with 2.618 ± 14 Ma. This age is interpreted as the age of the extrusion of the volcanic protolith. They would represent the two crustal preterit segments found in the region. During the Paleoproterozoic the Rio dos Mangues Complex was constituted, representing the most expressive unit of the basement. Ortogneisses of the Rio dos Mangues Complex were dated and their Pb-Pb in zircon ages varied between 2.054 ± 4 Ma and 2.086 ± 16 Ma. They were formed from a mantelic and juvenile source, with a small crustal contribution and their TDM ages are between 2.35 e 2.21 Ga. The geological processes that marked this period, involved crustal shortening with the participation of collision and thrusting that induced partial fusion of some parts of the thickened crust. The results were the generation of some igneous bodies (1.85 and 1.82 Ga) and of the Serrote Granite (1.86 Ga). Although the emplacement of the Serrote Granite took place at the end of the Paleoproterozoic, it was developed from older sources (2.50 e 2.43 Ga) than those of the Rio dos Mangues Complex. So, The continental crust established, with rocks from different ages and sources may be projected to the east, far from the studied area, inside the context of the architecture from the Atlantic Super Continent, formed definitively at the end of the Paleoproterozoic. At the end of a period without tectonic registers (end of Mesoproterozoic) a new phase took place in the region marked by tafrogenetic processes as the appearing of alkaline and basic magmatism as well as depositional basins that show an extensive context along the whole area. One of these basins received the sediments that originated the Araguaia Belt Supracrustals, which, during its evaluative process, reach the proto-rifte stage. Far from here, at the north portion of Goiás Massif, this rifting process seemed to permit the constitution of an oceanic domain, that, by evolution and recycling, may have be formed the rocks of the Magmatic Arc of Goiás. At the worked area, this arc terrain could be only be predicted by the appearing of one tonalitic gneiss with the age of 840 Ma and TDM model ages of 1.83 Ga. The effects of this tafrogenetic processes, from which the most important evidences are sienitic gneisses, found at Monte Santo Suit, with 1.051 ± 17 Ma, are related to the fission processes in the whole world which made the break up of the Rodinia Super Continent possible. The protolith of this suit were also been formed during the Mesoproterozoic as they can be seen in the TDM model age between 1.49 e 1.70 Ga. Finally, passing to the Neoproterozoic, through the inversion in the geodinamic conditions, processes of horizontal shortening again took place in the region, with the participation of crustal thickening as well as distinct volumetric and spatial fusions that may have generated the Matança and Santa Luzia Granites. The last one found inside the domain of Araguaia Belt. The Araguaia Belt was built from this tectonic motion, and has registers of past structural formations, also present in the older litostructural groups. The mass tectonic transport in the Amazonian Craton way might have occurred, resulting in the actual architecture found nowadays in the form of imbricated slices.
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