U–Pb geochronology and Lu–Hf zircon isotopy of the Santinho Granitic Association: A remnant of the early magmatic stages of the Florianópolis Batholith, Santa Catarina, Brazil

摘要: Abstract One of the main characteristics orogenic systems formed during assembly southwestern Gondwana in Late Neoproterozoic is widespread granitic magmatism. The Florianopolis Batholith South Brazil an excellent example this process, as it part a ca. 1400 km long intrusive association that key unit reconstruction paleogeography on both sides Atlantic. Santinho Granitic Association Island Santa Catarina exceptionally well-exposed section exhibiting complex lithological variety includes orthogneisses intruded by multiple generations leucogranite injections and associated with mafic magmatic enclaves. We present detailed geochronological study based field petrographic characterizations, which U–Pb LA-ICP-MS geochronology zircon, titanite monazite, well Lu–Hf isotopy zircon. Single-spot ages individual hand samples are determine process mostly extends between 640 600 Ma, average crystallization 625 605 Ma accordance relationships. Overlapping support coexistence different magma batches contrasting compositions reflect heterogeneous source rocks predominance old continental crust, indicated negative eHf values (−1.08 to −23.18) Hf TDM model 2.95 1.57 Ga. strong crustal affinity signatures enclaves suggests petrogenesis recycling older phases, instead representing direct mixing coeval mantellic new data, together deformational history recorded association, suggest represents early stages magmatism pre-to syn-collisional setting, preserved surrounding intrusions mega-xenolith.