Laguna del Desierto incident Laguna del Desierto region, the tribunal set the "hito 62" (cornerstone 62) at the O'Higgins/San Martin Lake and draw the boundary from there to mount Fitz Roy on the Martínez de Rozas Range awarding Chile the complete valley of Laguna del Desierto. In 1946 an aerial reconnaissance of the United States Air Force, ordered by the Chilean government, revealed that the lake emptied to the Atlantic shores. Chile and Argentina have to redraw its maps. The initially organized labour support for 1963 elected Argentine President Arturo Illia turned to antagonism during 1964, as secret plans for Juan Domingo Perón's return
Laguna del Maule (volcano) have been compared to the ones of Tronador volcano; additional compositional similarity is found to other volcanoes close to Laguna del Maule such as Cerro Azul and Calabozos. Laguna del Maule stands out for the frequency of rhyolitic rocks, compared to volcanoes farther south in the chain. There are compositional trends in the region of the volcanic arc between 33°-42°, with more northerly volcanoes being more andesitic in composition while to the south basalts are more frequent. All the postglacial activity appears to originate from a shallow silicic magma chamber beneath the caldera, which acts as a trap for mafic