phreatic explosion

The steaming vent area at Taal in the Philippines in September 1965, when the volcano produced a VEI 4 eruption. The Philippine Institute of Volcanology and Seismology (PHIVOLCS) has raised the alert status at Taal to Level 2 (of 4) and officials in the Philippines are getting ready if the volcano does come back to life for the first time since 1977. Taal is a mere 48 km (30 miles) from Manila - the capital of the Philippines and home to over 21,000,000 people in the metro area of the city. This location made Taal one of the UN/IAVCEI Decade Volcanoes as a large eruption from the volcano…
Mayon in the Philippines, taken in 2007 There has been a lot of waiting over the summer to see if Mayon in the Philippines was going to begin a new eruption sequence. This morning, the volcano had its first "eruption" since August 2008, producing a very small (~700 m / 2000 foot) ash-and-gas column that drifted to the southwest. PHIVOLCS reports that the plume had very minimal ash, but it is still worth noting. No new evacuations were called, but the 6-km "danger zone" and 7-8-km "extended danger zone" are still in effect. Mayon is one of the most active volcanoes in the Philippines, erupting…
Mayon erupting in August 2004. The increasing unrest at Mayon in the Philippines has prompted National Disaster Coordinating Council (NDCC) to recommend the evacuation of over 75,000 people from around the volcano. This, however, will only happen if the activity at the volcano continues to increase. The volcano currently sits at Alert Level 2 (increasing unrest) and if it were to increase to Level 3 (increased tendency towards eruption), then the evacuations of the first ~1,800 families closest to the volcano would begin. Only if the volcano reached Alert Level 4 (hazardous eruption imminent…
This week's edition of Wednesday Whatzits could have been called "Miércoles Materia" as all the updates are for South American volcano. Enjoy! Tungurahua in Ecuador (Note: all links in spanish) INGEOMINAS in Colombia is reporting that Nevado del Huila experienced 343 earthquakes over the past week, suggesting that something is brewing at the volcano. This has been accompanied by gas emissions and ash from the fractured dome. The Volcano Observatory in Popayán mentions that more than half of the earthquakes are related to magma moving into the system. Huila remains at Level III (Yellow)…
Canlaon volcano, Philippines Geothermal energy is one of those sources of energy that might be able to solve a lot of the planet's energy problems - heck, the Earth has a lot of heat it is trying to get rid of, so taking that heat and turning into energy seems like an easy (and clean?) way to stop using fossil fuels and the like. Of course, like any supposed panacea, it has its problems. However, one aspect that gets people are riled is whether drilling into areas of active magmatism might actually cause volcanism. Just in the last few weeks, a controversy was sparked in the Philippines when…
Image courtesy of KVERT, taken by L. Kotenko on Marhc 18, 2009. To me, one volcanic arc about which I wish I knew more is the Kuril-Kamchatka arc. I'm well aware of how active it is, with giants composite volcanoes like Bezymianny, Koryak, Klyuchevskoi and many, many others. This arc of volcanoes, although in a sparsely populated part of the world, is important to monitor due to its proximity of air travel lanes to Asia. So, any time I find out a volcano in this area - usually one that I was previously unfamiliar - erupted, I am excited. Today's example: Ebeko. Never heard of it. Yet, it is…
Image from AVO Hut webcam for Redoubt After an exciting few days ... well, OK ... after an exciting few hours on Sunday, AVO has decided to lower the alert level at Redoubt in Alaska to Yellow/Advisory. The alert level was lowered last week after seismicity at the volcano returned to normal after weeks of rumbling (at Orange/Watch status), but then we are all caught by surprise when a phreatic explosion occurred (and AVO returned the volcano to Orange). However, this didn't lead to a new period of heightened seismicity, so back to Yellow we go (even with elevated gas emissions and a nice…
Now that Redoubt has decided that Yellow/Advisory is not to its likely and has returned to an Orange/Watch status, I'll continue bringing new updates of the volcano has events unfold. And nothing much has unfolded since the phreatic explosion that occurred on Sunday. The current state of the volcano, according to AVO, is minor seismic unrest and that is about it. They do offer some more details of the events on Sunday: An AVO overflight Sunday witnessed activity from 11:30 AM until about 3:00 PM and was able to document ash emission from a new vent, just south of the 1990 lava dome and west…