Cerro Torta is a

dacitic 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 ...

lava dome 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 eruptions on ...

in Argentina. Approximately high, it covers an area of with of rocks. Cerro Torta is about 430,000 years old and is part of a recent volcanic series together with Cueros de Purulla and

Cerro Blanco Cerro Blanco is a hill and historical landmark in the city of Santiago, Chile. This geographic feature rises above the surrounding terrain and covers a surface area of . It is bordered by Recoleta Avenue on the east, Santos Dumont Avenue on ...

. A

seismic swarm In seismology, an earthquake swarm is a sequence of seismic events occurring in a local area within a relatively short period. The time span used to define a swarm varies, but may be days, months, or years. Such an energy release is different f ...

recorded on the 23 January 2009 at Cerro Torta most likely reflects underground movement of

magma Magma () is the molten or semi-molten natural material from which all igneous rocks are formed. Magma is found beneath the surface of the Earth, and evidence of magmatism has also been discovered on other terrestrial planets and some natural sa ...

, but a source in tectonic

faulting In geology, a fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust result from the action of plate tectonic ...

close to the dome is also possible. There are also underground anomalies in

seismic tomography Seismic tomography or seismotomography is a technique for imaging the subsurface of the Earth with seismic waves produced by earthquakes or explosions. P-, S-, and surface waves can be used for tomographic models of different resolutions based on ...

images. The dome lies in the

Central Volcanic Zone The Andean Volcanic Belt is a major volcanic belt along the Andean cordillera in Argentina, Bolivia, Chile, Colombia, Ecuador, and Peru. It is formed as a result of subduction of the Nazca Plate and Antarctic Plate underneath the South Americ ...

of the Andes, in the

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, ...

region. It is surrounded by

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

and

Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58Quaternary The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS). It follows the Neogene Period and spans from 2.58 million years ...

volcanoes in the area such as

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 ...

west-southwest and El Peinado north. Peinado and several

mafic A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks include ...

monogenetic volcano A monogenetic volcanic field is a type of volcanic field consisting of a group of small monogenetic volcanoes, each of which erupts only once, as opposed to polygenetic volcanoes, which erupt repeatedly over a period of time. The small monogenetic ...

es form an alignment with Cerro Torta.

San Francisco Pass The San Francisco Pass is a pass over the Andes mountains which connects Argentina and Chile. The highest point of this pass is at AMSL. Location The pass is located at and connects the Argentine province of Catamarca with the Atacama Re ...

is nearby.

References

Sources

* * * * * {{refend Pleistocene lava domes Volcanoes of Argentina