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The Wongwibinda Metamorphic Complex (WMC) of the southern New England Orogen exhibits small exposures of high-T–low-P metamorphic rocks that formed in an extensional accretionary orogen. A steep metamorphic field gradient provides the opportunity to compare virtually unmetamorphosed sedimentary rocks to high-grade metamorphic rocks (migmatite). The comparison of trace element and U-Pb-Hf-isotope composition of detrital zircon in rocks of variable metamorphic grade facilitated a better understanding of the processes that modify zircon during metamorphism and the identification of the protolith to the metamorphic rocks. The inferred protolith (Girrakool Beds) is dominantly well-bedded semi-pelitic to silicic mudstone with rare volcaniclastic sandstone interbeds. A comparison of the trace element and U-Pb-Hf-isotope composition of detrital zircon across the metamorphic sequence demonstrates that the Girrakool Beds are the protolith to all the metamorphic rocks within the Wongwibinda Metamorphic Complex. U-Pb geochronology of zircon grains separated from rocks and collected as alluvial grains in modern stream sediment identifies a maximum deposition age of c. 309 Ma. The majority of detrital zircon is c. 320–350 Ma with a peak at c. 330 Ma, and there are very few Proterozoic and Archean grains. The new zircon U-Pb geochronology supports petrographic evidence of a volcanic arc provenance for the Girrakool Beds. The trace element composition and