Dave Schumaker at Geology News has uploaded a fascinating time-lapse video from the USGS showing the growth of the lava dome at Mount St Helens between November 2004 and February 2008. The Cascades Volcano Observatory noted in a 21 February 2008 update that growth of the lava dome paused in late January 2008, and no growth has taken place since.

Given the dome-building process now under way at Chaitén, this video is a topical find. Unscientific musing: the St Helens dome looks quite sinister at times, although not as downright wicked-looking as the one at Kelut (image comes from here).

Geology News >> Video of Mount St. Helens Lava Dome Growth

Information
Smithsonian Institution Global Volcanism Program - summary information for Mount St Helens (1201-05-)
CVO Mount St. Helens - current activity information page from the USGS Cascades Volcano Observatory

The Volcanism Blog owes many grateful thanks to Werner Keller of the Villarrica and Llaima Volcanoes Visual Observation Project (POVI) in Chile for this picture of the Chaitén volcano lava dome, taken on 3 May 2008, the second day of the current eruption.

Above: the picture, taken from the south of the volcano, shows the currently active vent releasing its plume of ash and gas. The vent is located on the southern flank of the lava dome that occupies the 3.5-kilometre-wide caldera. The image, provided by Werner Keller, is copyright ONEMI.

The images below, taken from Google Earth and depicting the situation before the eruption, show the general situation of the volcano and the surrounding area. North is to the top in both images.

Above: close-up of the Chaitén caldera (from Google Earth). The currently erupting vent is on the lower, southern side of the lava dome, a little south-west of south, which also happens to be where the caldera rim is breached by a river.

Above: Chaitén town is a mere 10 kilometres from the volcano, and the river valley running between the two offers an ideal path for lava flows or pyroclastic surges to follow. The yellow line on the left is the coastline. On the right (i.e. to the east) is the massive volcano Minchinmávida, which was the first suspect when the eruption was reported last week.

 For all our Chaitén coverage: Chaitén << The Volcanism Blog

Information
Global Volcanism Program: Chaitén - summary information for Chaitén (1508-41)
ONEMI, Oficina Nacional de Emergencia - Chilean government emergencies office (Spanish)
SERNAGEOMIN - volcanology information from the Servicio Nacional de Geología y Minería, Chile (Spanish)

Apologies for the lack of recent postings: illness has intervened. There’s only the one of me, and when I’m sick things don’t get done. Fortunately things have been quiet, volcanically speaking, lately.

Back to normal by next week.

You may be interested to know that there is a new and already thriving group devoted to volcanoes on Facebook. The Volcanonet group was established on 17 December 2007 by Giovanni Leone of Lancaster University and is open to all volcano enthusiasts, wherever they are, to exchange ‘comments, ideas, views and even scientific research. Anyone is free to post links with interesting pictures, to add related photos, to show new findings or simply gorgeous views’. As of 1 January 2008 the group has over 500 members.

To join this group you have to join Facebook first by visiting their homepage and setting up a profile, which is free and relatively straightforward. Once you have set up your profile enter ‘volcanonet’ in the search box to access the group.