Ediacaran Águas Belas pluton, Northeastern Brazil: Evidence on age, emplacement and magma sources during Gondwana amalgamation

摘要: Abstract Ediacaran syenogranites from the Aguas Belas pluton, Borborema Province, Northeastern Brazil were investigated in this work. The studied granitoids show high SiO2, Fe# [FeO / (FeO + MgO)], total alkalis (K2O + Na2O) and BaO contents medium Sr low Nb contents. They gentle fractionated rare earth patterns with discrete Eu negative anomalies. Major trace element data point to chemical features of transitional high-K calc-alkaline alkaline post-collisional magmatism. Structural coupled geochronological suggest that NNE–SSW-trending sinistral movements at shear zones initiated ca. 590 Ma have activated E–W pre-existing structures current crustal level. synchronism these allowed dilation generate necessary space for emplacement pluton. U–Pb SHRIMP zircon a cluster ages around 588 ± 4 Ma which is interpreted as crystallization age. Some grain cores yielded within 2060–1860 Ma 1670–1570 Ma intervals. Oxygen isotope compositions grains distinct measured using techniques. Twenty three analyses same spots previously analyzed δ18O values ranging 5.79‰ 10.30‰ SMOW. This large range results variations both between (core–mantle/rim), result mixing components oxygen compositions. associated Paleoproterozoic Nd TDM model protolith involved mantle component (Paleoproterozoic lithospheric mantle), Mesoproterozoic igneous rocks. Interactions or Neoproterozoic supracrustal rocks, may occurred during intrusion. resulting magma evolved through biotite K-feldspar fractionation.