Volcano forecasts and Campi Flegrei

There are a few volcanoes that I do not feel comfortable writing about, and those are volcanoes that are far too close to large human settlements. The reason is obvious, it is far too likely that I will write about an event that will kill a lot of people. There are two ways to increase…

Images of Mount Fuji

In this land of many volcanoes, one mountain stands out. Few people will have heard of Ontake or Sakurajima – but everyone knows about Mount Fuji. It is the tallest of Japan’s volcanoes, 3776 meters high, with a summit crater which is 500 meter across. The smooth cone shows how young the surface is: this…

Greip, Gjálp’s Mysterious Sister

Mythology and Name In Norse mythology, there were two tempestuous giantesses, Gjálp and her sister Greip. They were the daughters of Geirröd, a giant who really didn’t like Thor… maybe it was hammer envy? Surprise surprise, Loki was involved as well, up to his usual tricks of winding people up and leaving joke-shop items lying around…

The winter of Huaynaputina

The mountain isn’t there. In its place, an explorer will find a double crater in the ground, several kilometers across, with thick ash on one side and an open side into a majestic river valley on the other. The debris is evidence of a violent past but it gives little hint of what was there…

Is that a volcano?

Someone once said that Iceland is one big volcano. Obviously, this is not true. In fact, it is not even one big volcanic system. Parts of Iceland are mainly powered by the Icelandic mantleplume, with just a bit of power coming from the spreading of the Mid Atlantic Ridge (MAR). Then there is a group…

Theistareykjarbunga – Iceland’s Slumbering Giant

Carl / Originally published December 2011 This is a re-post of an article by Carl, written long before (in impatient volcaholic time-scales) fellow giant Bárðarbunga’s eruption. The Five Large Volcanoes of Iceland Iceland holds five volcanoes that in historical time have had eruptions transcending the 10 cubic kilometer mark during post-glacial times. The most obvious are of…

Super interested in supervolcanoes?

A few days ago, I wrote that we are currently living in a volcanic low period. The last significant eruption happened on the 8th of August in 1991 and the culprit was Cerro Hudson. It was a medium sized VEI-5 eruption expelling roughly 4.5 cubic kilometres of ejecta. After that there has been a 26-year…

olcano? Erm... I don't see a volcano? Toba caldera wall seen from Samosir Island, a resurgent dome near the middle of the caldera. (Photo, Sebastian Hubarat, Tobaexplorer)

When Is a Caldera a Caldera?

Léon Prunelle / Originally published September 30, 2014 This is a re-post of an article by Henrik, written during the Bardarbunga eruption when the caldera had started its collapse. It does not take long for a newcomer to volcano-watching, if we are to call our hobby that, to come across the term “caldera”, cauldron. The term is…

The Dead Zone 2: The Sound of Silence

Although I’m more of an unseen hand (Volcanonati?) behind the scenes at VolcanoCafe and the VC Facebook group, I wanted to step out the shadows and give the Dead Zone article some new light. It’s an area I’ve always been fascinated with and it was this very area, along with its fissure eruptions, that first…

Deep magmatic roots of Katla…

For every person that is interested in volcanoes and complex geology, Iceland is probably something special. A unique place where the MAR intersects a mantle plume, or vice-versa. A beautiful island filled with powerful volcanoes and other complex volcanic and hydrothermal features. All in one nice little spot. Of the entire Icelandic volcanic lot, the most…