This (almost) daily post intends to follow up the activity changes of volcanoes all over the world.
This post is written by geologist Rodger Wilson who specializes in Volcano seismicity and Armand Vervaeck. Please feel free to tell us about new or changed activity if we haven't written about it. -
April 28, 2013 volcano activity
We start our daily overview with another great video from yesterday's Etna (Sicily, Italy) Paroxysm (short powerful eruption)
KVERT reported no significant changes in eruptive/seismic at the five active Kamchatkan volcanoes: Tolbachik, Sheveluch, Bezymianny, Kizimen, and Karymsky. Seismicity at Gorely volcano, which presently exhibits a high level of hydrothermal activity, remains at a moderate level.
Small shallow earthquakes continue in varying daily numbers at Iliamna volcano (Alaska Range) (station INE).
Several small earthquakes occurred at/near Mount Rainier (Cascade Range) (WA) (station RCS) and Mount Saint Helens (station VALT) today.
Seismic data from Colima volcano (Mexico) continue to be unavailable. The Colima volcanocam showed no obvious surface activity when viewed a few hours ago. Exhalations occurred at an average rate of nearly two events per hour at Popocatepetl volcano overnight. An exceptionally large outburst took place at the volcano earlier today and launched an ash-laden plume to over a kilometer in height above the cone. The Popo seismogram continues to show mainly low-level volcanic tremor occurring within/beneath the cone.
Volcanic tremor is high at Pacaya volcano (Guatemala) (station PCG) at this time, but surface activity has been relatively low. Small strombolian explosions, incandescent rockfalls from the snout of the newly extruded lava flow, and nearly continuous "locomotive sounds" characterize activity at Fuego volcano (station FG3) today. Small vulcanian explosions have recently increased from the Caliente dome at the Santiaguito Dome Complex (Santa Maria volcano ) (station STG3), some are visible on today's Santiaguito seismogram.
Volcanic tremor remains slightly elevated at San Cristobal volcano (Nicaragua) (station CRIN). Magnitudes of seismic events at Telica volcano (station TELN) have increased overnight, but their rate of occurrence has been only slightly above the "normal" high background level observed at the volcano. Volcanic tremor at Masaya volcano (station MASN) remains unstable, but has generally declined in amplitude over the past few days.
Higher-than-normal magnitude volcanic earthquakes continue at San Miguel volcano (El Salvador) (station VSM).
Local earthquakes and hydrothermal "noise" continue at Poas volcano (Costa Rica) (station POA2) today.
Seismicity remains unstable at Nevado Del Ruiz volcano (Colombia) (station OLLZ). Small earthquakes affect Sotara (station SOSO) and Cumbal (station MEVZ) volcanoes, and pulses of gas (and ash) emission tremor have recently appeared on seismograms at Galeras volcano (station CUVZ).
Eruptive activity has re-commenced at Tungurahua volcano (Ecuador) (station RETU) less than two days after we noted an increase in seismicity (see yesterday's report) at the volcano. Small earthquakes continue, though with reduced amplitudes today, at Cotopaxi volcano (station CO1V). Co-eruptive(?) seismicity has increased at Reventador volcano (station CONE) since yesterday.
Volcanic tremor continues its slow decline at White Island volcano (New Zealand), but surface hydrothermal activity remains strong there.
OMI satellite data have not been updated during the past few days (another victim of "The Sequester"?). Volcanic "hotspots" were identified in MODIS satellite images of Tolbachik, Fuego, Etna and Stromboli (Italy), and Batu Tara (eastern Java) volcanoes.