| Texto completo | |
| Autor(es): |
Avila, Carlos F.
;
Archanjo, Carlos J.
;
Viegas, Gustavo
;
Filho, Antomat A. Macedo
;
Hollanda, Maria Helena B. M.
Número total de Autores: 5
|
| Tipo de documento: | Artigo Científico |
| Fonte: | TECTONOPHYSICS; v. 912, p. 20-pg., 2025-07-25. |
| Resumo | |
Networks of interacting transcurrent shear zones are a hallmark feature of mid-to late-stage orogenic deformation and often drive significant displacement. In one of the largest of such systems on Earth, the Neoproterozoic Borborema Province of NE Brazil, shear zones with opposing shear senses are common but still poorly constrained in terms of relative chronology and total offset. High-resolution multispectral Sentinel 2 imagery from the vicinity of the junction of the left-lateral Taperoa<acute accent> and right-lateral Patos shear zones was processed to generate accurate and large-scale structural maps. Selective Principal Component Analysis was evaluated using simulated principal component scores of selected reference mineral spectra. False color Crosta composites yielded reliable lithological contrasts for extraction of lineaments and mapping of lithological units which are displaced by the Taperoa<acute accent> shear zone by 52 km. U-Pb ages obtained from the Lagoa do Meio (608 +/- 5 Ma) and Itapetim (617 +/- 5 Ma) plutons and their mapped continuous spatial connection along the shear zone core show their protracted crystallization history (potentially spanning more than 10 Myr) in a pre-transcurrent setting, due to their displacement of 52 km. Together with structural profiles of other key units, such as the 590 Ma alkaline granites and the c. 980 Ma host-regional metabasic units, these observations constitute kinematic evidence that the Taperoa<acute accent> shear zone was initiated after 590 Ma and grew in an intra-terrane setting. With this timing, it was potentially synchronous with early shearing of the Patos shear zone, thus constituting with it a dextral closing zipper. (AU) | |
| Processo FAPESP: | 22/03365-9 - Investigação geoquímica e geocronológica de enxames de diques gigantes associados a fragmentação do Gondwana Ocidental: elementos-chave para correlações geodinâmicas entre grandes províncias ígneas na América do Sul |
| Beneficiário: | Antomat Avelino de Macêdo Filho |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |