Volcanos

Roundup of Global Volcanic Activity

Stromboli (Eolian Islands, Italy): Lava continues to flow from the effusive vent under the NE crater and forms several active branches on the upper Sciara del Fuoco. When observed last evening, the most advanced flow fronts were at 500-550 m elevation. Near-constant glowing rockfalls detach from the lava flows, sometimes reaching the lower parts of the Sciara. Occasional ash emissions, sometimes with audible detonations occurred from the western vent at the summit craters.

Bardarbunga (Iceland): The eruption and seismic activity at the Holuhraun fissure continue with little variation. The Baardarbunga caldrta continues to subside at approx. 50 cm a day, accompanied by frequent earthquakes. Two magnitude 5.0 and 5.5 events yesterday were associated with a drop of the floor by approx. 60 cm alone! IMO wrote: "Seismic activity around Bárðarbunga, and volcanic activity at the eruption site at Holuhraun, has been comparable to recent days. Seismicity is low in the dyke intrusion; since the last report at 07:00 this morning around 15 earthquakes have been detected in the northern part of the dyke (less than 20 since midnight) and the strongest one was magnitude 1.1. About 25 earthquakes have been detected around the Bárðarbunga caldera rim during the last 12 hours (40 since midnight), the strongest event there was magnitude 5.5 at 10:22 on the southeastern rim (and since midnight a 5.0 earthquake on the northwestern rim at 03:51 must be included). Additionally, eight more earthquakes exceeded magnitude 3 since 07:00 (11 since midnight).

Copahue (Chile/Argentina): A new phase of ash emissions began on the evening of 4 Oct. The volcano started to emit near continuous ash plumes, interrupted by strong degassing phases, from the active El Agrio crater. Seismic activity according to SERNAGEOMIN has been low suggesting that the origin of the new eruptions is phreatic, i.e. driven by steam explosions rather than fresh magma rising to the surface. No incandescence has been observed, a further sign that the temperature is relatively low, typical for phreatic activity, and no thermal signal is visible on satellite data. Copahue volcano started a phase of unrest in late 2012 with seismic swarms and increased degassing. Its alert level was lowered back to Green in April 2013, but activity picked up shortly again, in May, and increased to the point that a magmatic eruption was considered a possibility. Volcanic alert level was raised to red, along with evacuations as precaution.