New geochemical, U–Pb SIMS geochronology and Lu–Hf isotopic data in zircon from Tandilia basement rocks, Río de la Plata craton, Argentina: Evidence of a sanukitoid precursor for some Paleoproterozoic granitoids

In this paper new geochemical, geochronological and isotopic Lu–Hf data from the Siempre Amigos Hills (SA), western Tandilia, Argentina, is presented. Outcrops in small area include representative lithologies of basement Río de la Plata craton (RPC) known as Tandilia Terrane. The geochemical characterize a heterogeneous Paleoproterozoic crust with similar U–Pb SIMS magmatic age (~2.1 Ga) represented by suite mafic (amphibolites, charnockitic granulites), intermediate felsic compositions (diorites, granodiorites granitic gneisses), well intrusive rocks (with Neoproterozoic ~652 Ma zircon). Geochemical features suggest processes differentiation igneous protolith associated ‘Camboriu orogeny’ Trans-Amazonian–Eburnean cycle. Some amphibolites may represent sanukitoid magmas to those formed at Archean-Proterozoic transition. This examines hypothesis precursor for RPC Rhyacian magmatism. potassic calc-alkaline character series, together negative Nb–Ta–Ti anomalies REE patterns, are compatible classical modern subduction-related magmas. Precise analyses zircons collected granodiorite gneiss indicate predominantly juvenile source (+εHf), minor crustal recycling (-εHf). An inheritance recorded single Neoarchaean zircon core (2771 ± 15 Ma), calculated maximum Hf TDM (2.8 Ga). Considering available region RPC, sustainable petrogenetic model proposed explain presence evidence magmatism which have occurred after 2.7 Ga, seems constitute series development arc Medium-to high-grade metamorphic conditions probably resulted subduction followed intrusion huge volumes configuration collage terranes, also consistent amalgamation various microcontinents formation Atlantica.