Nevado Ojos del Salado

Nevado Ojos del Salado
Name	Nevado Ojos del Salado
Elevation m	6893
Prominence m	3155
Range	Andes
Location	Argentina–Chile border
First ascent	1937

Nevado Ojos del Salado is a stratovolcano in the Andes on the Argentina–Chile border and is widely recognized as the highest active volcano on Earth and the second-highest mountain in the Western Hemisphere. It rises within the Atacama Desert region and dominates landscapes tied to the Puna de Atacama, Altiplano, and nearby features such as the San Pedro de Atacama area. Ojos del Salado has significance across multiple scientific fields, connecting to studies led from institutions like the Smithsonian Institution, Universidad de Chile, Universidad Nacional de San Juan, and observatories such as the ALMA Observatory and Cerro Tololo Inter-American Observatory.

Geography and Location

The mountain is situated in the Cuatros Candelaria sector of the Copiapó Province in Atacama Region, Chile, and the Copiapó Department of San Juan Province in Argentina, lying near provincial seats including Copiapó and San Juan City. Surrounding terrain includes the Laguna Verde (Atacama), Laguna Brava, the Salar de Maricunga, and neighboring peaks like Monte Pissis, Nevado Tres Cruces, Llullaillaco, and Pissis. The volcano is part of the Central Volcanic Zone and the Andean orogeny corridor that extends toward the Bolivian Altiplano and the Toconao basin. Major transport nodes providing access are linked to Calama, Chile Route 23, Ruta Nacional 149 (Argentina), and provincial roads connecting to Antofagasta and San Juan Province.

Geology and Volcanology

Ojos del Salado is a composite stratovolcano formed during the Neogene and Quaternary periods, with constructional deposits overlain by lavas and pyroclastics tied to activity recorded in regional surveys by the Servicio Nacional de Geología y Minería (SERNAGEOMIN), Servicio Geológico Minero Argentino (SEGEMAR), and the United States Geological Survey. Its magmatic history links to subduction along the Nazca Plate beneath the South American Plate and volcanic arcs including the Central Volcanic Zone. The edifice contains dacitic to andesitic lava flows and domes, with geochemical signatures compared to other Andean volcanoes like Llullaillaco, Lascar, Tucunire, and Irazu Volcano. Geological mapping has identified sector collapses, ashfall layers correlated to deposits in the Atacama Basin, and hydrothermal alteration reminiscent of systems at El Tatio, Salar de Atacama, and El Loa Province. Research by teams affiliated with Universidad de Buenos Aires, CONICET, and Instituto de Investigaciones Geológicas has used radiometric dating to constrain eruptive episodes, while petrological studies reference investigators such as F. G. C. Pereira and groups publishing in journals like Journal of Volcanology and Geothermal Research.

Climate and Glaciation

The mountain exists in an extreme high-elevation cold desert climate influenced by the Humboldt Current, South Pacific High, and continental subtropical anticyclone systems. Precipitation is minimal across the Atacama Desert rain shadow and is episodic, associated with phenomena including El Niño–Southern Oscillation and Pacific teleconnections monitored by the National Oceanic and Atmospheric Administration and European Centre for Medium-Range Weather Forecasts. Glacial remnants and perennial snowfields have been documented and compared with modern studies of tropical and subtropical glaciers such as those on Aconcagua, Huascarán, and Chimborazo. Cryospheric research teams from University of Innsbruck, Universidad de Magallanes, and University of Bern have applied remote sensing from satellites like Landsat, Sentinel-2, and ASTER to assess mass balance, while climate reconstructions reference ice core and palaeoenvironmental work connected to Paleoclimate studies and institutions such as IPCC modeling groups.

Human History and Cultural Significance

Indigenous presence in the region includes historical links to Diaguita, Atacameño (Likan Antai), and Quechua communities who traversed the Puna and high Andean corridors near ceremonial sites like those on Llullaillaco and altars akin to those documented at Inca trail networks. Spanish colonial exploration and mining linked the area to the Viceroyalty of Peru and later Argentine War of Independence era resource extraction centered on Copiapó and Potosí-era connections. Modern cultural interest ties to national identity in Chile and Argentina, with heritage authorities such as Consejo de Monumentos Nacionales (Chile) and Instituto Nacional de Antropología y Pensamiento Latinoamericano engaging in protection of archaeological finds. The volcano features in mountaineering chronicles by figures like René Kelle, Harold William Tilman, and regional guides catalogued by organizations including the American Alpine Club and Federación Argentina de Ski y Andinismo.

Mountaineering and Access

First recorded ascents occurred in the 20th century with documented climbs in 1937; subsequent routes developed from bases at high-altitude refuges and local staging points near Copiapó and Fiambalá. Common approaches use roads from Ruta 23 (Chile), Ruta 60-CH, and Ruta Nacional 149 (Argentina), with logistical support from outfitters operating in San Pedro de Atacama, Calama, Antofagasta, Catamarca Province, and La Rioja Province. Climbing history references ascents by international alpinists and expeditions organized through clubs such as the Alpine Club (UK), Club Andino de Chile, Club Andino Argentino, and commercial operators certified by national mountaineering federations. High-altitude physiology studies on acclimatization and hypoxia have been conducted by groups at University of Colorado Boulder, Harvard Medical School, and Instituto Nacional de Medicina Aeronáutica to inform safe ascent practices. Rescue and emergency response involve coordination with agencies like Policía de Investigaciones de Chile and Gendarmería de la Provincia de San Juan for cross-border incidents.

Flora and Fauna

Vegetation is sparse, reflecting high-elevation puna and altiplano biomes with plant assemblages related to genera recorded in the High Andes flora inventories compiled by CONAF and botanical teams from Missouri Botanical Garden, National Botanic Garden of Wales, and Royal Botanic Gardens, Kew. Species of cushion plants, Azorella relatives, and high Andean grasses inhabit lower slopes near wetlands such as those in the Salar de Maricunga, while fauna includes records of vicuña, guanaco, Andean condor, Andean fox (culpeo), and migratory waterbirds observed at highland lagoons. Biodiversity assessments conducted by WWF and regional conservation NGOs reference pressures from mining interests tied to corporations operating in the Atacama Region and collaborate with agencies including Ministerio del Medio Ambiente (Chile) and Administración de Parques Nacionales (Argentina) for habitat protection.

Category:Volcanoes of Chile Category:Volcanoes of Argentina Category:Andean_volcanoes