Geochemistry and Geochronology of Early Paleozoic Intrusive Rocks in the Terra Nova Bay Area, Northern Victoria Land, Antarctica

The Terra Nova Intrusive Complex (TNIC) in northern Victoria Land, Antarctica, results from widespread magmatism during the Early Paleozoic Ross Orogeny. According to field relationships, geochemistry, and geochronology data, part of TNIC comprises Browning Unit (BIU), which is associated with an arc crustal melting including migmatization Wilson Metamorphic Complex, later Campbell (CIU), attributed mantle processes. Zircon U-Pb ages suggest Late Neoproterozoic Cambrian protolith metamorphism (502 ± 15 Ma) WMC, formation (~500 BIU, Ordovician (~480–470 CIU. Sr-Nd isotopic characteristics BIU indicate predominant component (εNd(t) = −8.7 −8.9), whereas those CIU reflect both 1.8 1.6) −4.0 −7.5) compositions. These that occurring at ~500–470 Ma originated partial mantle–mafic crust components mixing felsic components. By integrating previous studies, considered be formed by a combination mafic melting, assimilation, magma