Patagonian Ice Sheet Ice Sheet resulted in a dramatic release of freshwater to the adjacent ocean, decreasing its salinity and altering its circulation, resulting in significant ecological changes both locally and remotely. Patagonian Ice Sheet The Patagonian Ice Sheet was a large elongated and narrow ice sheet centered in the southern Andes that existed during the Llanquihue glaciation. The ice sheet covered all of Chile south of Puerto Montt plus the western fringes of Argentine Patagonia. The ice sheet extended beyond the crest of the Andes into Argentina, but because of the dryness of the climate it did not reach beyond present-day lakes
North Patagonian Massif North Patagonian Massif The North Patagonian Massif or Somún Cura Massif (Spanish: "Macizo Norpatagónico", "Macizo Nordpatagónico" or "Macizo de Somún Cura") is a massif in northern Patagonia located in the Argentine provinces of Río Negro and Chubut. The massif is a plateau surrounded by sedimentary basins. The North Patagonian Massif covers an area of approximately . The massif rises above the surrounding topography reaching a maximum of above sea level. Compared to neighboring areas, the North Patagonian Massif has thicker continental crust. The massif consists of a basement formed by Cambro-Ordovician rocks, overlain by the Middle Silurian Sierra Grande Formation.