Aguilera est un volcan dacitique dans les Andes chiliennes plus au sud et situé à l'ouest du lac Argentine et NE de Peel Fjiord. Son histoire géologique est mal connus, mais il y Aguilera doit avoir eu une grosse éruption explosive inférieur à environ 3600 ans, qui a laissé une couche de tephra éminents. Aguilera appartient à la Zone volcanique de Australandean du sud de la Patagonie.

Explosive eruption of Aguilera volcano 3600 years ago

A large explosive eruption occurred at Aguilera volcano about 3600 years ago and is recognized by the "A1" tephra layer. The eruption was Plinian in size and erupted ca. 4-9 cubic km of magma. The A1 white tephra layer is deposited in thick sections along the shores of Lago Argentino. It is absent on Tierra del Fuego, but has a very wide distribution north of the Strait of Magellan. At 80 km distance, the airfall tephra layer is still over 10 cm thick and more than 5 cm thick in 130 km distance east of the volcano. This suggests that the wind was blowing from the SW at the time of the eruption and the plume drifted NE.

The pumice of the A1 tephra contains the mineral biotite as phenocrysts, which has not been found in other lavas of Aguilera.



Sources:

- Smithsonian / GVP Aguilera volcano information

- Charles R. Stern (2008) "Holocene tephrochronology record of large explosive eruptions in the southernmost Patagonian Andes", Bull. Volc., Volume 70, Number 4, pp. 435-454