Deformation mechanisms, mineral chemistry and zircon U-Pb geochronological constraints in the south Patos shear zone: implications for the crustal evolution of the Borborema Province, NE Brazil
Abstract The southern boundary of the Patos Shear Zone (PSZ) is characterized by mylonites resulting from the deformation of Paleoproterozoic basement gneisses, Neoproterozoic metavolcanic and metasedimentary rocks, granitic and granodioritic intrusions. Among the latter, the Santa Terezinha and Cat...
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| Format: | Article |
| Language: | English |
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Sociedade Brasileira de Geologia
2022-01-01
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| Series: | Brazilian Journal of Geology |
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| Online Access: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S2317-48892021000400306&lng=en&tlng=en |
| _version_ | 1818942490735017984 |
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| author | Carolina Peixoto de Souza Luis Gustavo Ferreira Viegas Lauro Cézar Montefalco de Lira Santos |
| author_facet | Carolina Peixoto de Souza Luis Gustavo Ferreira Viegas Lauro Cézar Montefalco de Lira Santos |
| author_sort | Carolina Peixoto de Souza |
| collection | DOAJ |
| description | Abstract The southern boundary of the Patos Shear Zone (PSZ) is characterized by mylonites resulting from the deformation of Paleoproterozoic basement gneisses, Neoproterozoic metavolcanic and metasedimentary rocks, granitic and granodioritic intrusions. Among the latter, the Santa Terezinha and Catingueira plutons show stretched shapes in agreement with the the shear zone’s regional trend. Recrystallized quartz grains in these plutons accommodate deformation by dislocation creep. The host banded gneisses show similar deformation structures to the plutons. Quartz crystallographic fabrics mainly record the activity of basal and prism slip planes with local contribution of rhomb planes, whilst feldspar clasts show evidence of intracrystalline deformation in the larger porphyroclasts. These characteristics suggest that shearing occurred at lower-amphibolite facies conditions. U-Pb zircon data for the Santa Terezinha pluton yields an age of 625 ± 7 Ma, which, coupled with the pluton elongated shape and microstructure, suggests that its emplacement was pre-kinematic in relation to the Patos shear zone. Post-emplacement elongation of the granite body occurred along the strike-slip trend. Such structural and geochronological constraints highlight the close association between magma emplacement and shear zone deformation during distinct stages of the Brasiliano-Pan-African orogeny in the Borborema Province. |
| first_indexed | 2024-12-20T07:12:16Z |
| format | Article |
| id | doaj.art-300cedbc409e4bd7bfb173a9cd2db2d5 |
| institution | Directory Open Access Journal |
| issn | 2317-4692 |
| language | English |
| last_indexed | 2024-12-20T07:12:16Z |
| publishDate | 2022-01-01 |
| publisher | Sociedade Brasileira de Geologia |
| record_format | Article |
| series | Brazilian Journal of Geology |
| spelling | doaj.art-300cedbc409e4bd7bfb173a9cd2db2d52022-12-21T19:48:52ZengSociedade Brasileira de GeologiaBrazilian Journal of Geology2317-46922022-01-0151410.1590/2317-4889202120210048Deformation mechanisms, mineral chemistry and zircon U-Pb geochronological constraints in the south Patos shear zone: implications for the crustal evolution of the Borborema Province, NE BrazilCarolina Peixoto de Souzahttps://orcid.org/0000-0001-7186-2693Luis Gustavo Ferreira Viegashttps://orcid.org/0000-0002-9945-6256Lauro Cézar Montefalco de Lira Santoshttps://orcid.org/0000-0001-6098-1873Abstract The southern boundary of the Patos Shear Zone (PSZ) is characterized by mylonites resulting from the deformation of Paleoproterozoic basement gneisses, Neoproterozoic metavolcanic and metasedimentary rocks, granitic and granodioritic intrusions. Among the latter, the Santa Terezinha and Catingueira plutons show stretched shapes in agreement with the the shear zone’s regional trend. Recrystallized quartz grains in these plutons accommodate deformation by dislocation creep. The host banded gneisses show similar deformation structures to the plutons. Quartz crystallographic fabrics mainly record the activity of basal and prism slip planes with local contribution of rhomb planes, whilst feldspar clasts show evidence of intracrystalline deformation in the larger porphyroclasts. These characteristics suggest that shearing occurred at lower-amphibolite facies conditions. U-Pb zircon data for the Santa Terezinha pluton yields an age of 625 ± 7 Ma, which, coupled with the pluton elongated shape and microstructure, suggests that its emplacement was pre-kinematic in relation to the Patos shear zone. Post-emplacement elongation of the granite body occurred along the strike-slip trend. Such structural and geochronological constraints highlight the close association between magma emplacement and shear zone deformation during distinct stages of the Brasiliano-Pan-African orogeny in the Borborema Province.http://www.scielo.br/scielo.php?script=sci_arttext&pid=S2317-48892021000400306&lng=en&tlng=enPatos shear zonegranitic magmatismmicrostructuresgeochronologydeformation mechanisms |
| spellingShingle | Carolina Peixoto de Souza Luis Gustavo Ferreira Viegas Lauro Cézar Montefalco de Lira Santos Deformation mechanisms, mineral chemistry and zircon U-Pb geochronological constraints in the south Patos shear zone: implications for the crustal evolution of the Borborema Province, NE Brazil Brazilian Journal of Geology Patos shear zone granitic magmatism microstructures geochronology deformation mechanisms |
| title | Deformation mechanisms, mineral chemistry and zircon U-Pb geochronological constraints in the south Patos shear zone: implications for the crustal evolution of the Borborema Province, NE Brazil |
| title_full | Deformation mechanisms, mineral chemistry and zircon U-Pb geochronological constraints in the south Patos shear zone: implications for the crustal evolution of the Borborema Province, NE Brazil |
| title_fullStr | Deformation mechanisms, mineral chemistry and zircon U-Pb geochronological constraints in the south Patos shear zone: implications for the crustal evolution of the Borborema Province, NE Brazil |
| title_full_unstemmed | Deformation mechanisms, mineral chemistry and zircon U-Pb geochronological constraints in the south Patos shear zone: implications for the crustal evolution of the Borborema Province, NE Brazil |
| title_short | Deformation mechanisms, mineral chemistry and zircon U-Pb geochronological constraints in the south Patos shear zone: implications for the crustal evolution of the Borborema Province, NE Brazil |
| title_sort | deformation mechanisms mineral chemistry and zircon u pb geochronological constraints in the south patos shear zone implications for the crustal evolution of the borborema province ne brazil |
| topic | Patos shear zone granitic magmatism microstructures geochronology deformation mechanisms |
| url | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S2317-48892021000400306&lng=en&tlng=en |
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