Is something up at Shishaldin?

Shishaldin volcano in Alaska.

Yesterday I mentioned in the SI/USGS Weekly Report update that things appear to be afoot at Shishaldin in the Aleutians. Well, I checked the Shishaldin webicorder today and indeed, [SPECULATION] something seems suspect. Now, the increasing signal might be wholly unrelated to any magmatic activity, but it is interesting to see an increase in the seismicity after the increase in the intensity of thermal anomaly at the summit crater.

AVO’s latest statement (from yesterday) seems to think that nothing too much is up:

Cloudy conditions prevented views of Shishaldin today but it is likely that the thermal anomaly persists at the summit crater. Seismic, deformation, and gas emission data do not show anything abnormal at the volcano, and there is currently no indication that an eruption will occur. AVO will continue to carefully monitor activity at Shishaldin.

Shashaldin, located on Unimak Island, is possibly one of the most picturesque volcanoes on the planet. It is beautifully symmetrical and when covered with snow (as it is most of the time), it is a “textbook stratocone”. The volcano tends to produce explosive (strombolian) basaltic eruptions with some lava flows. Shashaldin may have had a small eruption in 2008, but the last confirmed eruption was in 2004, when a VEI 2 eruption produced explosions and some ash fall. In 1999, the volcano had a VEI 3 eruption that also produced lahars. Shilshaldin has been very active since the mid-1800s, so a new eruption at the volcano would definitely not be surprising.