Magallanes Basin
The Magallanes Basin or Austral Basin is a major sedimentary basin in southern Patagonia. The basin covers a surface of about 170.000–200.000 km2 and has a NNW-SSE oriented shape. The basin bounds to the west with the Andes mountains and is separated from the Malvinas Basin to the east by the Río Chico-Dungeness High. The basin evolved from being an extensional back-arc basin in the Mesozoic to being a compressional foreland basin in the Cenozoic. Rocks within it derive from the Jurassic Period and includes the Cerro Toro formation.
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