Southern Patagonian Ice Field in the area, among which are the Upsala (765 km), Viedma (978 km) and Perito Moreno (258 km) in the Los Glaciares National Park in Argentina, and the Pío XI Glacier or Bruggen Glacier (1,265 km, the largest in area and longest in the southern hemisphere outside of Antarctica), O'Higgins (820 km), Grey (270 km) and Tyndall (331 km) in Chile. The glaciers going to the west flow into the fjords of the Patagonian channels of the Pacific Ocean; those going to the East flow into the Patagonian lakes Viedma and Argentino, and eventually, through the rivers "de la Leona"
Patagonian Desert contributing to the gravel sediments covering parts of the Patagonian. The desert is quite windy as well, a result of the rain shadow effect and descending cool mountain air. This wind helps make the Patagonian one of the largest sources of dust over the South Atlantic Ocean. On the west the Patagonian grasslands portion of the Patagonian Desert are bounded by nothofagus forests of the Magellanic subpolar forests. Volcanic rocks covers more than 120,000 km of the Patagonian Desert, mainly in the "Somun Cura Massif" (i.e. North Patagonian Massif) and the "Deseado Massif". Some other volcanic areas include the Pali-Aike