Escorial volcanCerro Escorial volcano is a small andesitic-dacitic stratovolcano in northern Chile on the border with Argentina. The volcano contains a 1 km wide well-preserved summit crater of possible Holocene age. There are young-looking lava flows mostly towards the Chilean side, but they are probably more than 300,000 years old.
A large sulfur mine active until around 1978, La Casualidad or Mina Julia, is located 4 km SW of the volcano in an area of extensive hydrothermal alteration. A present, the volcano has warm springs (frozen at the surface), mud vents, and fumaroles, suggesting that the volcano is still active.
Introduction:Cerro Escorial is the youngest volcanic center of the NW-SE-trending Corrida de Cori range that marks the Chile/Argentina border.
A prominent ignimbrite sheet was erupted ca. 460,000 years ago from Cerro Escorial during a large explosive eruption. The pyroclastic flows who deposited the ignimbrite were generated by eruption column collapse and deposited only on the lower flanks all around the volcano, reaching up to 10 km distance from the vent. The ignimbrite covers approximately 105 sq km, with a maximum thickness of 6 m, and has a maximum total volume of 0.6 cubic km. Except where it is overlain by a few younger lava lobes in the SW, it is well exposed and forms a prominent stratigraphic marker horizon.
Very youthful-looking lava flows extend westward 3-4 km over the ignimbrite deposit on the Chilean side, but they, too, are relatively old compared to their aspect (ca. 340-320,000 years).
Most of the lava flows from Escorial extend to the SW into Chile, but a few small lobes traveled NE on the Argentinian side of the volcano.
The most recent feature seems to be the summit crater itself. Sattered andesitic lava blocks up to 50 cm in diameter can be found near the summit, and are ballistic blocks ejected during the most recent, possibly Holocene, explosions from the crater.
- Smithsonian / GVP volcano information
- Richards, J. P. and Villeneuve, M. (2002) "Characteristics of late Cenozoic volcanism along the Archibarca lineament from Cerro Llullaillaco to Corrida de Cori, northwest Argentina", J. Volcanology and Geothermal Research, v. 116 (3-4), pp. 161-200
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