Motta, Rafael Gonçalves daAntunes, Ramon Junger Ferreira2020-02-132021-09-202020-02-132021-09-202019-12-13ANTUNES, Ramon Junger Ferreira. Mapeamento geológico e caracterização petrográfica da região de Serra das Flechas, município de Pedra Lavrada-PB. 2019. 85f. Trabalho de Conclusão de Curso ((Bacharelado em Geologia) - Departamento de Geologia, Universidade Federal do Rio Grande do Norte, Natal, 2019.https://repositorio.ufrn.br/handle/123456789/34370This work presents a geological and petrographic study of the Serra das Flechas region, located in the western part of the municipality of Pedra Lavrada, in the state of Paraíba. Given the potential for mineral resources and the consequent disposition for mineral exploration in the region, the geological mapping, at scale of 1: 30,000, together with the petrographic analysis of the observed lithotypes intend to contribute with new information and more detail. The study area is geotectonically located at north of the Borborema Province in the Rio Grande do Norte Domain and covers two tectonoestratigraphic terrains, which are separated by the Picuí-João Câmara Shear Zone: the Rio Piranhas-Seridó Domain, covering most of the area, to the east of the shear zone; and the São José do Campestre Domain to the west. At first, aerogeophysical data and remote sensing products, as well as a compilation of bibliographic data and previous maps assisted in the identification and characterization of lithostratigraphic units and main structures. This set of information, together with the data collected in the field stage allowed the elaboration of the geological map of the area. To the east of the shear zone, we mapped and identified orthognaisses and migmatites, which correspond to the paleoproterozoic basement, the Serrinha-Pedro Velho Complex. In the west, we interpreted the outcropping units as being the neoproterozoic metasupracrustal rocks of the Seridó Group, which we identified by the presence of schists, as well as marble, amphibolite and chalcosilicate rock lenses, that belong to the Jucurutu Formation. The predominant unit comprises the biotite garnet schists, with portions containing cordierite, sillimanite and andalusite, that belong to the Seridó Formation of the Seridó Group. These units are intruded by the peraluminous monzogranites of the Jardim do Seridó Suite, the sienogranites of the alkaline Caxexa Suite, and finally by the dykes and pegmatitic bodies that mark the end of the Ediacaran-Cambrian magmatism. We recognized three tectono-metamorphic events (D1/M1, D2/M2 e D3/M3) in which consist the geological evolution of the region. The first one (D1/M1) is only registered in the basement rocks, and is attributed to the gneissification and migmatisation of the paleoproterozoic granitoids, defining a high metamorphic degree at superior amphibolite facies. The D2/M2 event corresponds to a tangential tectonics, characterized by intrafolial folds and tight recumbents that affect both the basement and the metasediments of the Seridó Group, reaching the amphibolite facies. The last event (D3/M3), responsible for the current structural configuration of the area, occurred in transcurrent regime, accompanied by intense plutonism. The third event produced macrostructures such as the Picuí-João Câmara dextral shear zone and the moderate to strong dip axial plane folds with rotated flanks that form a large inverted anticline. The metamorphism (M3) associated with this event is characterized by high temperatures and low pressures, reaching the upper amphibolite facies at its metamorphic peak, while retrometamorphism reached the green schist facies. The last two events characterize a collisional context associated with a transcurrent regime, which point to the processes of collage and dispersion of terrains that is characteristic of the Brasiliano orogeny.Mapeamento geológicoPetrografiaMetamorfismoGeologic mappingPetrologyMetamorphismbachelorThesis