Geochronological constraints on the evolution of the southern Dom Feliciano Belt (Uruguay)

New U-Pb sensitive high-resolution ion microprobe, K-Ar and Ar-Ar data from the southernmost Dom Feliciano Belt allow the identification of four major events. Orthogneisses front the Punia del Este Terrane indicate a magmatic episode at c. 770 Ma and high-grade metamorphism at 641 +/- 17 Ma. Granitoid emplacement at 627 +/- 23 Ma was roughly coeval with peak metamorphism. Volcaniclastic rocks of the Las Ventanas Formation dated at 573 +/- 11 Ma can be correlated with the peripheral foreland basin (571 +/- 8 Ma). Transpression and coeval high-K calc-alkaline magmatism is recorded in the Maldonado granite dated at 564 +/- 7 Ma. The following events are postulated: (1) magmatism at 850-750 Ma related to rifting (2) metamorphism and granite emplacement at 650-600 Ma; (3) molasse sequences and foreland basins at c. 573 Ma: (4) late magmatism at 580-560 Ma associated with transpression. The data indicate that (1) the Punta del Este Terrane could be a portion of the Coastal Terrane of the Kaoko Belt, (2) granitoid emplacement at 650-600 Ma in the Punta del Este and Nico Perez terranes favours westward subduction, and (3) widespread post-collisional synkinematic magmatism occurred in the Dom Feliciano and Kaoko belts between 580 and 550 Ma.