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 into the logs, thus fossilizing the trees and creating one of the world's best preserved petrified forests in the desert's center. The Patagonian is mainly composed of gravel plains and plateaus with sandstone canyons and clay shapes dotting the landscape, sculpted by the desert wind. The region encompassing the desert, however, has many diverse features. Ephemeral rivers, lakes, and drainage deposits from the Andes' spring melt form annually, hosting a variety of waterfowl and aquatic grasses. A variety of glacial, fluvial, and volcanic deposits are also found in the region and have significantly affected the desert's climate over time, especially