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(Reference retrieved automatically from SciELO through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Late Ediacaran lateral-escape tectonics as recorded by the Patos shear zone (Borborema Province, NE Brazil)

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Carlos José Archanjo [1] ; Maria Helena Bezerra Maia de Hollanda [2] ; Luis Gustavo Ferreira Viegas [3]
Total Authors: 3
[1] Universidade de São Paulo. Instituto de Geociências - Brasil
[2] Universidade de São Paulo. Instituto de Geociências - Brasil
[3] Universidade de Brasília. Instituto de Geociências - Brasil
Total Affiliations: 3
Document type: Journal article
Source: BRAZILIAN JOURNAL OF GEOLOGY; v. 51, n. 2, p. -, 2021.
Web of Science Citations: 3

Abstract Lateral escape tectonics mediated by strike-slip fault zones are an efficient mechanism of rock deformation in the continental crust of collision zones. The Borborema shear zone system, which shows dimensions comparable to the Cenozoic extrusion of Indochina, defines a lateral escape setting of the Brasilano orogeny in Northeastern Brazil. In this paper, the timing of high-grade metamorphism and compositions of the terranes involved in the shear deformation were investigated. The Patos shear corridor deforms the Siderian to Neoarchean rocks of the Granjeiro Complex that, in turn, form the basement of Seridó-Lavras da Mangabeira metapelites. U-Pb zircon ages and Sm-Nd whole-rock isotopic compositions indicate that the 2.80 – 2.35 Ga basement sequences mainly include juvenile material, whereas zircons from synkinematic migmatites indicate that the partial melting occurred in the Late Ediacaran (ca. 565 Ma). Cooling rates provided by 40Ar/39Ar range from 12 to 17°C/Ma, indicating a differential shear zone exhumation, in agreement with a transpressive setting. The presence of allochthonous Siderian sequences dismembered along the shear zone suggests that the Seridó-Granjeiro corridor defines a major tectonic boundary connected to the collisional front defined by the convergence of São Francisco-Congo and Amazonian cratons. (AU)

FAPESP's process: 14/01114-2 - Strain localization at the frictional-viscous transition in the middle crust: examples from the Pernambuco shear zone (Borborema Province, NE Brazil)
Grantee:Luís Gustavo Ferreira Viegas
Support type: Scholarships abroad - Research Internship - Post-doctor