Mapeamento geológico de uma área localizada em parte dos municípios de Jardim de Piranhas e Timbaúba dos Batistas/RN

Abstract

To the southeast of the urban area of Jardim de Piranhas / RN, an area covering part of the territory of Jardim de Piranhas and Timbaúba dos Batistas, in the region of Seridó Potiguar, was mapped. This region has significant potential for mineral exploration. The geological characterization at the site identified as main rocks: orthogneisses (banded and migmatized), paragnaisses and amphibolites of the Caicó Complex; and orthogneisses augen from the Poço da Cruz Suite. Less frequently, there are Neoproterozoic granitoids, tectono-hydrothermal quartzites, marbles and lenses of calcisilitic rocks. The last three lithotypes are from hydrothermalism in the shear zone. The outcrop analysis defines four deformational events (D1, D2, D3 and D4) and their respective metamorphic episodes (M1, M2 and M3). The first three deformational events are ductile in character, while the fourth and last are brittle. Only the D1/M1 event reached only the rocks of the Caicó Complex. In the third event, intrusions of Neoproterozoic granitoids occur and shear zones with preferential trend NE-SW are generated, as well as a vertical foliation called S3, which can evolve to milonitic surfaces along these zones. The percolation of hydrothermal fluids during shear favors mineral substitutions, generating, from gneisses and granitoids, protomylonitic, mylonitic, calcisilitic and tectonic quartzite rocks. Based on all the information obtained, a map was created on a 1:30,000 scale through which a review of the previous available data and characterization of structures is carried out.