Los Patos (also known as Tres Quebradas) is a mountain in the

Andes The Andes, Andes Mountains or Andean Mountains (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long, wide (widest between 18°S – 20°S ...

mountain range of

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the sout ...

. The peak is located on the international border of the Catamarca Province of

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

and the Atacama Region of

Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the east a ...

. It has a summit elevation of . Los Patos is a

volcano A volcano is a rupture in the Crust (geology), crust of a Planet#Planetary-mass objects, planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and volcanic gas, gases to escape from a magma chamber below the surface. On Ear ...

. Potassium-argon dating on

dacite Dacite () is a volcanic rock formed by rapid solidification of lava that is high in silica and low in alkali metal oxides. It has a fine-grained (aphanitic) to porphyritic texture and is intermediate in composition between andesite and rhyolite ...

taken from the northern flank showed an age of 4,550,000 ± 180,000 years ago. At that time, volcanic activity in the Maricunga Belt had just ended and was shifting towards the area of

Ojos del Salado Nevado Ojos del Salado is a dormant complex volcano in the Andes on the Argentina–Chile border. It is the highest volcano on Earth and the highest peak in Chile. The upper reaches of Ojos del Salado consist of several overlapping lava domes, ...

and

Nevado Tres Cruces Nevado Tres Cruces is a massif of volcanic origin in the Andes Mountains on the border of Argentina and Chile. It has two main summits, Tres Cruces Sur at and Tres Cruces Centro at and a third minor summit, Tres Cruces Norte . Tres Cruces Sur ...

. Another date obtained on the lower part of the volcano is 7,600,000 ± 600,000 years ago. The base of Nevado Tres Cruces rises immediately east of Los Patos. Los Patos is part of the Cordillera Sundt, a mountain chain containing

stratovolcanoes A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and peri ...

with

lava domes In volcanology, a lava dome is a circular mound-shaped protrusion resulting from the slow extrusion of viscous lava from a volcano. Dome-building eruptions are common, particularly in convergent plate boundary settings. Around 6% of erupti ...

and

lava flows Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or un ...

. The chain is constructed by dacite and smaller amounts of

andesite Andesite () is a volcanic rock of intermediate composition. In a general sense, it is the intermediate type between silica-poor basalt and silica-rich rhyolite. It is fine-grained (aphanitic) to porphyritic in texture, and is composed predo ...

. Other volcanoes in the chain include

Falso Azufre Falso Azufre is a complex volcano at the border of Argentina and Chile. Falso Azufre is elongated in east–west direction and contains craters and lava domes; most craters have diameters of with the exception of the main crater, which is wi ...

Monte Pissis Monte Pissis is an extinct volcano on the border of La Rioja and Catamarca provinces, Argentina, from the Chilean border. The mountain is the third-highest in the Western Hemisphere, and is located about north of Aconcagua. Monte Pissis is ...

and Mulas Muertas. So-called "Pircas Negras" lavas with compositions similar to

adakite Adakites are volcanic rocks of intermediate to felsic composition that have geochemical characteristics of magma originally thought to have formed by partial melting of altered basalt that is subducted below volcanic arcs. Most magmas derived ...

have been found on the northern flanks of Los Patos. They contain amphibole and

clinopyroxene The pyroxenes (commonly abbreviated to ''Px'') are a group of important rock-forming inosilicate minerals found in many igneous and metamorphic rocks. Pyroxenes have the general formula , where X represents calcium (Ca), sodium (Na), iron (Fe I ...

as the dominant minerals and some samples have been found at and .

References

External links

*
"Tres Quebradas, Argentina/Chile" on Peakbagger
Mountains of Argentina Mountains of Chile Volcanoes of Atacama Region Volcanoes of Catamarca Province Six-thousanders of the Andes Mountains of Atacama Region Mountains of Catamarca Province Stratovolcanoes of Argentina Stratovolcanoes of Chile Miocene stratovolcanoes Pliocene stratovolcanoes {{Catamarca-geo-stub

See also

References

External links