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This work represents a synthesis of current geological knowledge of the Boa Vista city, Roraima state, Brazil. The methodology was based on literature review and data obtained from field surveys by researchers from geology course at the Federal University of Roraima. The main objective is to provide updated information to society about the geology and mineral resources of the municipality, aimed at dissemination of geological knowledge, assisting in the public policies planning, and action of rational occupation of the physical environment. [ABSTRACT FROM AUTHOR]

Abstract: Metagranitoid rocks, mylonites, leucogneisses and granulites occur in the Central Guyana Domain (CGD) near the Uatumã-Anauá Domain (UAD) boundary, southeastern Roraima (Brazil). These rocks are oriented along NE–SW and E–W trends and dip to NW and N, respectively. Single-zircon Pb evaporation results yielded 1724±14Ma and 1889±3Ma for a syn-kinematic foliated hornblende–biotite monzogranite and a granodioritic mylonite, respectively. These results point to a new tectonic event (Itã Event) in the area in addition to the 1.94–1.93Ga (late- to post-Transamazonian) and the 1.35–0.98Ga (K’Mudku) thermal tectonic events. This new event may be related, at least locally, with the evolution of the Columbia Supercontinent. In addition, the Itã Fault System is younger than 1.89Ga (granodioritic mylonite age), contrasting with the Barauana high-grade lineament and 1.94Ga polydeformed rocks, pointing to the needs of a major revision of lithostratigraphic column currently proposed for the CGD as well as the CGD and UAD boundary. [Copyright &y& Elsevier]