Aspectos tect?′nicos do emplacement da borda leste do Complexo Gran?-tico Tr?as C?3rregos, Cerro Azul (PR)

摘要

During the neoproterozoic collisions related to the ending of Brazilian Cycle, several magmatic events took place in the southern??Ribeira Belt, producing large granitic intrusions held in different tectonic environments. The Tr?as C?3rregos granitic suit is??one of the most important magmatic records owing to its expressive and tectonic significance, with several plutons developed??in a complex evolution and polyphasic tectonic conditions involving variables during their emplacements. The structural pattern??and petrotectonic records of the border of granites and theirs country rocks suggests distinct stages to the emplacement of??different facies in the eastern border, were are recognize S?￡o Sebasti?￡o and Arrieiros a?? Cerro Azul granitic units ( s.l facies), intrude??in metavolcano-sedimentary rocks of Agua Clara formation. Those country rocks are associated to mesoproterozoic basins,??deformed and metamorphosed during the neoproterozoic history, with early thrust belts stages and to transcurrent shear??zones. For the study of the evolution of the Tr?as C?3rregos granitic suit and related wall rocks in an integrated approach, this??research was developed applying structural and petrotectonic analysis together with geophysical data interpretation. The early??stages of Apia?- terrane deformation were characterized by a thrust tectonic event, which one developed S 1 and S 2 foliations in??the metavolcanossedimentary rocks of ??gua Clara formation. The eastern portion of Tr?as C?3rregos Granitic Suit shows a low??dip angle magmatic foliation, even in the regions near by the limits with wall rocks, suggesting an active tectonics condition??during the emplacement. The metamorphic records also support this hypothesis, having been generated under pressure and??temperature conditions compatible with the overlap of the emplacement processes by the development thrust shear zones.??.