TY - DATA T1 - Anatectic reworking and differentiation of continental crust along the active margin of Gondwana: a zircon Hf–O perspective from West Antarctica PY - 2016/06/21 AU - Chris Yakymchuk AU - Christine S. Siddoway AU - C. Mark Fanning AU - Rory Mcfadden AU - Fawna J. Korhonen AU - Michael Brown UR - https://geolsoc.figshare.com/articles/dataset/Anatectic_reworking_and_differentiation_of_continental_crust_along_the_active_margin_of_Gondwana_a_zircon_Hf_O_perspective___from_West_Antarctica/3453362 DO - 10.6084/m9.figshare.3453362.v1 L4 - https://ndownloader.figshare.com/files/5422475 L4 - https://ndownloader.figshare.com/files/5422478 KW - crustal reworking v KW - Gondwana KW - crustal growth KW - source KW - Palaeozoic turbidite sequence KW - Hf KW - West Antarctica KW - crustal differentiation events KW - zircon KW - Devonian KW - granite KW - Geology N2 - The Fosdick migmatite–granite complex of West Antarctica preserves evidence of two crustal differentiation events along a segment of the former active margin of Gondwana, one in the Devonian–Carboniferous and another in the Cretaceous. The Hf–O isotope composition of zircons from Devonian–Carboniferous granites is explained by mixing of material from two crustal sources represented by the high-grade metamorphosed equivalents of a Lower Palaeozoic turbidite sequence and a Devonian calc-alkaline plutonic suite, consistent with an interpretation that the Devonian–Carboniferous granites record crustal reworking without input from a more juvenile source. The Hf–O isotope composition of zircons from Cretaceous granites reflects those same two sources, together with a contribution from a more juvenile source that is most evident in the detachment-hosted, youngest granites. The relatively non-radiogenic εHf isotope characteristics of zircons from the Fosdick complex granites are similar those from the Permo-Triassic granites from the Antarctic Peninsula. However, the Fosdick complex granites contrast with coeval granites in other localities along and across the former active margin of Gondwana, including the Tasmanides of Australia and the Western Province of New Zealand, where the wider range of more radiogenic εHf values of zircon suggests that crustal growth through the addition of juvenile material plays a larger role in granite genesis. These new results highlight prominent arc-parallel and arc-normal variations in the mechanisms and timing of crustal reworking v. crustal growth along the former active margin of Gondwana. ER -