By now it should be no secret that I am a sucker for big calderas and lava domes. This week’s volcano has a bit of both, and is among good company down in Ecuador, where it shares the mainland and Galapagos Islands with 34 other volcanic systems. But one only has to venture a little bit west of Ecuador’s capital city of Quito to visit one of the most active volcanoes of the country, a pair of volcanic peaks that are part of a broad volcanic massif called Guagua Pichincha.
The two peaks are separately called Guagua Pichincha and Rucu Pichincha. “Guagua” (sometimes spelled “wawa” in the Kichwa language of the indigenous people of that area means “baby”, and likewise “rucu” means “old person”. The older caldera is thought to have ceased activity around 200,000 years ago, but remains well preserved. The younger Guagua Pinchacha is actually a steep sided 6 km wide caldera that is breached to the west. The event that led to the caldera collapse occurred around 50,000 years ago, though according to this research, the slope failure happened later, around 23,000 years ago. A stratovolcano called Toaza now rises inside the collapsed caldera, but the most recent activity has originated within the caldera just north of Toaza where a lava dome named Cristal, some fumaroles, and a small active crater lie.
Guagua Pichincha’s eruptive history is mostly minor phreatic eruptions with the occasional growth and destruction of a lava dome. Its largest historically recorded eruption happened in 1660, a plinian event lasting only 12 hours, but depositing ash as far as 300 km away. The city of Quito recieved 30 cm of ashfall, but was fortunate the the topography of old Rucu Pichincha interceded and kept the pyroclastic flows well away from the city.As a historical note, there was a battle fought on the slopes of Pichincha volcano on 24 May 1822 as part of the Spanish American war for independence. The victory against the colonial army loyal to Spain eventually led to Ecuador’s independence.
These days, the Pichincha volcanoes are a popular hiking destination. A favourite attraction is the Quito TelefériQo, a cable car that carries sightseers a distance of 2,237 m in eight minutes, climbing a breathtaking 828 m up the lower flanks of Rucu Pichincha. From there, hikers can summit the older volcano on foot.
Here’s a (somewhat long) video of the trip up Rucu
Congratulations Aficientifico for finding me first, with Glenn coming up second. Next week I hope to challenge both of you and see if I can extend a virtual volcano vacation beyond three or four days. Tune in Monday around 23:00 NYC-time when I begin a new adventure at a new volcano.