Age of granitoid magmatism in South Georgia and correlations to southern Patagonia and the northern Antarctic Peninsula

South Georgia forms one of the most isolated fragments of continental crust on Earth and lies in a remote location in the Southern Ocean. Its geology is dominated by Early Cretaceous back-arc turbidite successions that are in faulted contact with a late Palaeozoic – early Mesozoic accretionary complex. The accretionary complex includes fragments of a deformed accretionary prism and ophiolite that are intruded by a suite of granitoid plutons that are dated here. Granitoid magmatism has been identified from the Middle Jurassic (c. 163 Ma) and Late Cretaceous (c. 107 Ma, c. 86 Ma), which can be correlated with convergent margin magmatism from the southern (Fuegian) Andes and Cordillera Darwin of southern Patagonia, and the northern Antarctic Peninsula, with the Late Cretaceous magmatism restricted to the western parts of each area. These correlations support earlier findings that established a contiguous relationship between the southeast sector of South Georgia and southernmost Patagonia (south of the Magallanes fault zone) and the northern sector of Graham Land (Antarctic Peninsula).

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