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) early Quaternary volcanic centres, are also found around the field. Northeast of Laguna del Maule is the high Cerro Campanario, a mafic stratovolcano which was active 150,000–160,000 years ago. Nevado de Longavi volcano is located west of Laguna del Maule. The local volcanoes are in a segment of the crust where the Wadati-Benioff zone is deep. Also west of Laguna del Maule lies the Tatara-San Pedro and Rio Colorado caldera; they may be part of a volcano alignment with Laguna del Maule. More distant are the Calabozos caldera and a late Pleistocene system with domes and flows south of Cerro