Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10119919 | Journal of South American Earth Sciences | 2018 | 57 Pages |
Abstract
New U-Pb SHRIMP dating in zircon and titanite showed that the three large Paleoproterozoic A-type granite Suites and related granites from Carajás Province of the Amazon Craton (Brazil) were emplaced between 1880â¯Ma and 1857â¯Ma, with the main magmatic peak at 1880â¯Ma. Some particular ages not reported before have been identified: (i) ages of 1865â¯Ma to 1857â¯Ma in leucogranite facies of the Redenção and Bannach plutons, that are younger, were generated by independent magma pulses and are not cogenetic with the dominant â¼1880â¯Ma old granites of the respective plutons; (ii) an age of 1732â¯Â±â¯6â¯Ma obtained in the leucogranite facies of the Antônio Vicente pluton of the Velho Guilherme Suite that could represent a magmatic event in the Xingu Region not yet reported or, eventually, could correspond to an isolate hydrothermal event that allowed the growth of zircons. The more detailed geochronological data obtained in the Paleoproteozoic A-type granites of Carajás Province, added to the information available in the literature, demonstrate the relevance of the magmatic event at â¼1880â¯Ma and indicate that the emplacement of those granites was done in about â¼20 m.y. that means in a relatively short geological time. This 1880â¯Ma magmatic episode was also intense in other provinces of the Amazon Craton, where it is linked mostly to the formation of the Uatumã Silicic Large Igneous Province. This event was mostly extensional and isalso registered in several cratons worldwide demonstrating its relevance in the tectonic evolution of Proterozoic continents.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Earth and Planetary Sciences (General)
Authors
Mayara Fraeda Barbosa Teixeira, Roberto Dall'Agnol, João Orestes Schneider Santos, Davis Carvalho de Oliveira, Claudio Nery Lamarão, Neal J. McNaughton,