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Pocho volcanic field

Coordinates: 31°50′S 65°20′W / 31.833°S 65.333°W / -31.833; -65.333[1]
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31°50′S 65°20′W / 31.833°S 65.333°W / -31.833; -65.333[1]

Pocho volcanic field is a volcanic field in Argentina.[2] It is associated with a crustal lineament known as the Ojo de Agua Lineament.[3]

It is located in the Sierras de Cordoba mountain chain.[4] It formed during the late Miocene, when a progressive shallowing of the subducting Nazca Plate caused volcanic activity to retreat 500 kilometres (310 mi) from the main Andes into the land behind the mountain chain.[2] This did result in a typical shallow slab chemistry of the Pocho rocks.[4] Volcanic activity at Pocho is dated about 4.7 +- 0.3 million years ago[5] and took place over two cycles.[6] Seismic activity in the area may indicate the presence of a residual magma chamber however,[7] which would also explain anomalous crustal seismic velocities in the area.[8]

References

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  1. ^ Coira, B.; Kay, S. Mahlburg; Viramonte, J. (1993-08-01). "Upper Cenozoic Magmatic Evolution of the Argentine Puna—a Model for Changing Subduction Geometry". International Geology Review. 35 (8): 697. doi:10.1080/00206819309465552. ISSN 0020-6814.
  2. ^ a b Stern, Charles R. (2004-12-01). "Active Andean volcanism: its geologic and tectonic setting". Revista Geológica de Chile. 31 (2): 161–206. doi:10.4067/S0716-02082004000200001. ISSN 0716-0208.
  3. ^ Caro Montero, Ana; Martino, Roberto D.; Guereschi, Alina B. (January 2018). "Anomalously deep earthquakes related to the Ojo de Agua Lineament and its tectonic significance, Sierras Pampeanas of Córdoba, Central Argentina". Geodesy and Geodynamics. 9 (1): 90. doi:10.1016/j.geog.2017.10.001. hdl:11336/88737.
  4. ^ a b Jones, Rosemary E.; Kirstein, Linda A.; Kasemann, Simone A.; Litvak, Vanesa D.; Poma, Stella; Alonso, Ricardo N.; Hinton, Richard (2016-10-01). "The role of changing geodynamics in the progressive contamination of Late Cretaceous to Late Miocene arc magmas in the southern Central Andes". Lithos. 262: 169–191. doi:10.1016/j.lithos.2016.07.002. hdl:20.500.11820/93c1babf-4765-49fb-aa71-73c9410bb9e6.
  5. ^ Ramos, Victor A.; Folguera, Andrés (2009-01-01). "Andean flat-slab subduction through time". Geological Society, London, Special Publications. 327 (1): 31–54. CiteSeerX 10.1.1.1002.5325. doi:10.1144/SP327.3. ISSN 0305-8719. S2CID 43604314.
  6. ^ Caro Montero, Ana; Martino, Roberto D.; Guereschi, Alina B. (January 2018). "Anomalously deep earthquakes related to the Ojo de Agua Lineament and its tectonic significance, Sierras Pampeanas of Córdoba, Central Argentina". Geodesy and Geodynamics. 9 (1): 78–82. doi:10.1016/j.geog.2017.10.001. hdl:11336/88737.
  7. ^ Caro Montero, Ana; Martino, Roberto D.; Guereschi, Alina B. (January 2018). "Anomalously deep earthquakes related to the Ojo de Agua Lineament and its tectonic significance, Sierras Pampeanas of Córdoba, Central Argentina". Geodesy and Geodynamics. 9 (1): 90. doi:10.1016/j.geog.2017.10.001. hdl:11336/88737.
  8. ^ Ammirati, Jean-Baptiste; Venerdini, Agostina; Alcacer, Juan Manuel; Alvarado, Patricia; Miranda, Silvia; Gilbert, Hersh (August 2018). "New insights on regional tectonics and basement composition beneath the eastern Sierras Pampeanas (Argentine back-arc region) from seismological and gravity data". Tectonophysics. 740–741: 42–52. doi:10.1016/j.tecto.2018.05.015. hdl:11336/86785. S2CID 133702507.
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