The geology of Uruguay combines areas of Precambrian-aged shield units with a region of volcanic rock erupted during the Cretaceous and copious sedimentary facies the oldest of which date from the Devonian.
[3] The later orogenic event is the result of the accretion of blocks and terranes in the aftermath of the breakup of Rodinia when São Francisco and Río de la Plata cratons formed one plate in the west of the Adamastor Ocean.
[3] West of Sarandí del Yí Shear Zone the Río de la Plata Craton is intruded by the Late Paleoproterozoic Florida dyke swarm.
Sedimentary rocks of Lower Devonian age are found in the central part of Uruguay being exposed as a narrow east-west to northeast oriented band.
[8] During the early rifting stages of the South Atlantic the area of southern Paraná Basin suffered a gentle uplifting that deviated sediments into the Tacuarembó region of Uruguay.