Near the southern tip of South America, a trio of volcanoes lines up perpendicular to the Andes Mountains. The most active is the westernmost, Volcán Villarrica, pictured in this photo-like image from the Advanced Land Imager on NASA’s Earth Observing-1 (EO-1) satellite on May 15, 2010.
The 2,582-meter (9,357-foot) stratovolcano is mantled by a 30-square-kilometer (10-square-mile) glacier field, most of it amassed south and east of the summit in a basin made by a caldera depression. To the east and northeast, the glacier is covered by ash and other volcanic debris, giving it a rumpled, brown look.
The western slopes are streaked with innumerable gray-brown gullies, the paths of lava and mudflows (lahars). Beyond the reach of ash and debris deposits, the volcano is surrounded by forests; the area is a national park. The biggest recent eruption was in the early 1970s; lava flows melted glaciers and generated lahars that spread at speeds of 30–40 kilometers per hour (20-30 mph) toward Lago Villarrica (visible to the northwest in large image) and southwest toward Lago Calafquéen (lower left).
NASA Earth Observatory image by Jesse Allen and Robert Simmon, using EO-1 ALI data provided courtesy of the NASA EO-1 team. Caption by Rebecca Lindsey.
Rivera, A., Corripio, J. G., Brock, B., Clavero, J., & Wendt, J. (2008). Monitoring ice-capped active Volcán Villarrica, southern Chile, using terrestrial photography combined with automatic weather stations and global positioning systems. Journal of Glaciology, 54(188), 920Ã¢â¬â930.
Brüggen Glacier in southern Chile is the largest western outflow from the Southern Patagonian Ice Field and, unlike most glaciers worldwide, advanced significantly since 1945. From 1945 to 1976, Brüggen surged 5 km across the Eyre Fjord, reaching the western shore by 1962 and cutting off Lake Greve from the sea.