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The Goochland terrane in the central Piedmont Province of Virginia contains two documented units of Mesoproterozoic age, the State Farm Gneiss (ca. 1023–1046 Ma) and the Montpelier Anorthosite (ca. 1045 Ma). The heterogeneous Maidens gneiss, the most extensive unit in the terrane, has previously been assumed to be Mesoproterozoic. This inferred age was based primarily on the presence of locally preserved granulite-facies assemblages (particularly in metapelites), with granulite conditions assumed to reflect metamorphism accompanying the Grenville orogeny. However, we report new U-Pb zircon results for meta-igneous varieties of Maidens gneiss that indicate Paleozoic (Devonian) crystallization ages. Whole-rock major- and trace-element compositions of these and additional samples suggest intermediate igneous protoliths of high-K, calc-alkaline affinity. Our age determinations clearly demonstrate that the protoliths for these samples were not Mesoproterozoic, and could not have been affected by Grenvillian metamorphism. As an alternative, we suggest that the protoliths were plutonic igneous rocks, reflecting deep-seated emplacement of magmas approximately coincident with high-grade metamorphism in associated rocks during the Acadian orogeny. Whether our age results can be applied to the entirety of the Maidens gneiss is uncertain, but if so, a large portion of the Goochland terrane as currently defined is not Mesoproterozoic.

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