A long-lived active margin revealed by zircon U–Pb–Hf data from the Rio Apa Terrane (Brazil): New insights into the Paleoproterozoic evolution of the Amazonian Craton

Abstract

We present the first regional in-situ zircon U–Pb–Hf isotopic data from metaigneous and metasedimentary rocks from the Paleo- to Mesoproterozoic Rio Apa Terrane (RAT), a crustal fragment outcropping in the central-western Brazil and north-eastern Paraguay. These new ages and Hf isotopic data delineate three magmatic events, which record the construction of the temporally and isotopically distinct Western and Eastern Terranes of the RAT. The Western Terrane comprises the 2100–1940 Ma Porto Murtinho Complex and the 1900–1840 Ma Amoguijá Belt, which both define a crustal reworking array in εHfT-time space evolving from a precursor source with Hf TDM age of ca. 2700 Ma. The 1800–1720 Ma Caracol ..