This week I once again found myself (or hid myself, actually) in the “ring of fire” where volcanoes grow in abundance. But even along that ring of tectonic subduction along the margins of the Pacific Plate, it seems certain regions produce volcanoes of exceptional vitality, height, or intrinsic volcanic beauty. Chile is one such place, having 77 named volcanic edifices listed on Global Volcanism Program’s site. But of all those volcanoes, one seems to be almost universally agreed upon by those who know volcanoes as being among the world’s most beautiful volcanoes. She is also one of Chile’s most active….and it was only a matter of time before I was found at Volcán Villarrica.
Villarrica is a 2.847 m tall and strikingly symmetrical basaltic to basaltic-andesite stratovolcano that lies at the western end of a group of three large volcanoes on an older fault that runs perpendicular to the Liquiñe-Ofqui Fault which aligns with the Northern Patagonian Andes.
Villarrica’s ancestral volcano was constructed during the Middle Pleistocene starting around 100,000 years ago.. The eruption of the Licán Ignimbrite around 14,000 years ago produced the 6.5 X 4.2 km eliptical outer caldera surrounding the present-day volcano. In 1810 BCE (give or take 200 years), the VEI 5 eruption of the Pucón Ignimbrite produced the smaller 2 km caldera in the northwest corner of the Pleistocene caldera; the former of which is mostly filled by the modern volcano. Ignimbrites, being the deposits of pyroclastic flows or surges, are somewhat unusual from a mafic volcano such as Villarrica. Her modern eruptive style tends toward strombolian or effusive.
Villarrica’s upper flanks stay snow-covered year-round and are home to 40 square kilometers of glaciers. The volume of the glaciers shrank by 25% between 1961 and 2003, most likely due to ash from eruptions. The darker ash absorbs solar radiation, warming and melting the ice below, however if the ash deposites over a glacier are thicker than 5 cm, the incredible insulating properties of the volcanic material actually help protect and preserve the ice below. It is ironic that a volcano can actually be beneficial to a glacier. Still, the presence of so much snow and ice means that Villarrica is prone to deadly lahars.
Villarrica also belongs to a very exclusive list of volcanoes having active lava lakes, though Villarrica’s is only intermittent. The small lake, perhaps 5 m wide, first appeared in the early 1980s. The summit crater is frequently active and a glow can often be seen at night reflecting in the clouds or volcanic steam above. It is believed the constant degassing of the lava at the lake causes the lava to become more viscous and therefore more explosive.
Villarrica shares its name given to it by the conquering Spanish with a nearby lake and town, but before then, it was called Rucapillán, a name in the language of the indigenous Mapuche people which means “house of Pillán”. A Pillan is one or a group of respected male spirits of the Mapuche mythology, believed to be for the most part benevolent but also known to deal out punishment in the form of natural disasters or plagues. A human who leads a righteous and lawful life can ascend to become a Pillan. Though some reside in a spiritual world of pure goodness, other Pillan make their homes on Earth inside volcanoes. It is my personal opinion that the latter would be sufficient motivation for better behaviour in this mortal realm…but I would have a lot to make up for first.
I suppose if I ever ascended, it would be less like the image above though, and more like this video below.
The viewer will note that despite the alerts and evacuation, the spectators seem to be enjoying the show. 🙂
Also, if you want to see what Villarrica is up to right now, there are three webcams to choose from
Thanks to Jesper I have been found once again…for better or for worse. Also, I hope I have resolved the issue at this blog with replies and notifications. A theme-upgrade seems to have fixed most of the issues I was having with admin functions and reviewing replies, though there still seems to be some lag between WordPress and my email inbox. I will be adding my secondary email address (firstname.lastname@example.org) to the sidebar in case anybody needs to send feedback about unanswered replies or page-loading issues. Minor updates to this blog’s appearance will likely happen throughout next week, but I hope VVVc #88 will still happen on a regular schedule (with maybe a tad of lateness) this coming Monday. You know how it goes…new adventure..new volcano…so be there or be square!