| Autor: |
Vargas Pilla Dias, João Rodrigo, Charão Marques, Juliana, Bertolini, Gabriel, Carlos Frantz, José, Friedrich, Betina, da Silva Paim, Jhenifer Caroline, Sobrinho da Silveira, Carlos José, Alves Queiroz, Waldemir José |
| Předmět: |
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| Zdroj: |
Brazilian Journal of Geology; 2022, Vol. 52 Issue 1, p1-14, 14p |
| Abstrakt: |
The Cr-rich Jacurici Complex is located at the limit between the Serrinha Block and the Salvador-Curaçá Belt, Northeastern São Francisco Craton. In order to better understand the age span of magmatism and tectonism, we have studied a basement high-grade charnockite orthogneiss, a metanorite of the Complex and a crosscuting undeformed quartz-feldspar pegmatite. For the orthogneiss, SHRIMP U-Pb ages of zircon cores and overgrowth rims yielded, 2966 ± 9 Ma for crystallization and 2091 ± 10 Ma for metamorphism, respectively. Zircons from the metanorite show internal textures consistent with high grade metamorphism. The U-Pb LA-ICP-MS age determination provided a 2099 ± 6 Ma metamorphic age for the Jacurici Complex, indicating it was already emplaced during amalgamation around 2.1 Ga. Zircons from the undeformed quartz-feldspar pegmatite provided a LA-ICP-MS U-Pb age of 2083 ± 11Ma, marking the end of the N-S transcurrence. The magmatic Jacurici Complex age remains undefined, but is equal to, or older than, 2.1 Ga. Therefore, possible correlations with other mafic-ultramafic intrusions, such as the Cu-rich Caraíba Complex, should be reassessed. Our results indicate that the N-S transcurrence ended earlier in the Jacurici Complex region than in the northwestern area of the Salvador-Curaçá belt. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
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