The northwestern Borborema Province is known, by the geological point of view, for the diversity of granitic bodies by magmatism, chronology and significance of magmatic events in the regional context, producing magmatic-metamorphic terrains of high complexity, representing advanced stages generation of magmas during deformational processes. In this context, the Brasiliano event is very important because of its regional domain that affected all the Borborema Province and its development relative to global geotectonic changes that involve continental collages, orogens formation, closing of oceans, as a series of pulses magmatic that extended throughout the event, forming large migmatitic-granitic suites, marking various episodes of deformation and injections of magma. From the progress of knowledge of the northwestern state of Ceará with the data presented and the most recent research as chemical and geochronological analyzes in known granitic bodies, seeks to better understand these magmatic events, their timing and context in the formation of rock units that make up the current framework of the northwestern Borborema Province. In this sense, the Granito do Pajé is an example that needed a review/confirmation of data by geochronological methods more accurated which were also used for a comparative study with other granites best known in this region. Previous geochronological studies performed by Rb-Sr method in whole rock, obtained age of 537 ± 21 Ma for the Granito do Pajé. As is known, the Rb-Sr method has limitations in its use when seeking lithogenic events in complex areas and has been most commonly used for dating the last thermal event, due to lack of precision caused by various factors that give unsatisfactory results or dubious value in terms of age of crystallization of the rock. This work in the form of TCC aimed the determination of the age of the Granito do Pajé using techniques and methods precise dating, such as the method Pb-Pb, besides petrographic analyses, enhancing its characteristics, and a study of their contact relations with the basement rocks. Furthermore, isotopic analyzes were performed by Sm-Nd method to discuss the sources of generation of this granite. The age of crystallization obtained by the method Pb-Pb in zircon was 528.9 ± 3.7 Ma, demonstrating that the crystallization of the Granito do Pajé happened at the end of the Neoproterozoic, beginning of the Paleozoic, and may be included in Meruoca Intrusive Suite, thus giving it the same kind of context tectonic crustal generation and positioning of the main representatives
granites of this magmatic event as Meruoca, Mucambo and Serra da Barriga. The Sm-Nd method was performed on two samples of the Granito do Pajé and the results for the sample 2011/PAJÉ-03 gives model age of 1.99 Ga and value of εNd (530 Ma) = –11,90. For the sample 2011/PAJÉ-02 the model age was 1.79 Ga with value of εNd (530 Ma) = – 9,11. Negative values suggest crustal contribution in these granitic magma generator and model age indicates the age of the igneous protolith which gave rise to these rocks.
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