Eruption Update for June 19, 2012: Nevado del Ruiz and Popocatépetl

By Erik Klemetti
June 19, 2012 |

A comparison of the summit region of Nevado del Ruiz seen in April 2010 and June 2012. Image courtesy of NASA and INGEOMINAS.

I thought I'd post a brief update on the action at two Latin American volcanoes as a break from working on this lovely NSF proposal.

Nevado del Ruiz, Colombia

Quite a few reports have come out of Colombia talking of the continued ash emissions from Ruiz. However, the activity is mostly on the same level as it has been for the last few weeks – plumes that reach a few kilometers and dust the region in ash. A source from INGEOMINAS says that as of a week ago, no juvenile material has been found in the ash, so all the activity is likely to be phreatic (steam-driven) as magma rises under the volcano (but doesn't reach the surface). The latest update from the Volcano Observatory in Manizales reports that small earthquakes at depths of 3-5 km and volcanic tremor continue, although the steam and ash plume is only a few hundred meters today. INGEOMINAS also posted a few comparison images of the crater of Ruiz, showing it in April 2010 and June 2012. You can clearly see how much ash has already been deposited at the summit of the volcano – and in another image, how directional the ash fall has been, with the northwestern side of the volcano covered in grey and and the southeastern side still almost pure white.

Hundreds of people who live along some of the river draining from the volcano have also been evacuated as a precaution and the alert level remains at Orange (suggesting an eruption in "days to weeks".) Even with this relatively low level of activity at Ruiz, the economic impact of the activity is being felt already – the airports in the region (Manizales, Pereira and Armenia) have been closed for almost three weeks with hundreds of cancelled flights, causing some fears that companies at the airport will start to close due to the lost business. Remember, you can check out the webcams for Ruiz to see what's up.

Popocatépetl, Mexico

Webcam image of potential small lahars in drainages on the side of Popocatépetl in Mexico. Image capture courtesy of Eruptions reader Barbbeier and CENAPRED.

The rumblings at Popocatépetl continue as well. It is funny, if you look at the news coverage of the activity, you'd think it was all about "exhalacion" counting – almost every article is something like "the volcano has [fill in number] explosions in the last 24 hours" and if the number of small explosions goes up or down a little, it somehow signifies something important. The latest report has "only" 17 explosions, lower than the 50-80 from earlier this month. Unfortunately for the news media, it isn't that easy – these explosions will wax and wane as the system heats up, but merely counting them isn't likely to be a precise predictor of the future of the activity. A few eagle-eyed Eruptions readers did notice some small mudflows on the upper slopes of Popocatepetl (see above) on the CENAPRED webcams, an important hazard to note for people living near the volcano. The ash might be a nuisance, but lahars could be deadly if people are not warned and evacuated.