LAUSR

Abstract Two granitoid plutons (Piloezinhos and Curral de Cima) intruded along the Remigio - Pocinhos shear zone, eastern part of the Borborema Province. The Piloezinhos and Curral de Cima granites were dated at 566 ± 3 Ma and 618 ± 5 Ma respectively. The granitoids from both plutons have distinct initial 143 Nd/ 144 Nd ratios, expressed by eNd(t) values, i.e. the granitoids of Piloezinhos pluton have lower eNd(t) values (−15.47 to −15.81) and negative eHf (t = 570 Ma) values (−16.0 to −18.6), while the granitoids of the Curral de Cima pluton have eNd(t) values between −1.12 and −5.23. The granitoids of the Curral de Cima pluton are epidote bearing, magnesian calcalkaline I-type granitoids, crystallized under high fO 2 conditions. The granitoids of the Piloezinhos pluton are alkaline, low-fO 2 , ferroan, ilmenite-series, A2-type granite intrusions. The geochemical and isotopic signatures suggest that the origin of magma of the Curral de Cima granitoids involved mixing/mingling at depth between crustal and mantle magmas, associated to decompression (lateral escape) during the convergent stage of Brasiliano/Pan/African orogeny, which lead the asthenosphere melts to rise into the lower crust. The source of magma of the granitoids of the Piloezinhos pluton involved a strong crustal component with geochemical and isotopic signatures similar to the orthogneisses of the Serrinha-Pedro Velho Complex, and small mantle component. The emplacement of the Piloezinhos pluton is associated to an extensional space formed during high-T strike-slip shearing developed by the synchronic movement of the Matinhas sinistral shear zone and Remigio - Pocinhos dextral shear zone.