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. -
February 27, 2013 volcano activity
The Instituto Geofisico del Peru reports a strong volcano-tectonic earthquake swarm struck Sabancaya volcano between 22 and 23 February. The swarm consisted of 560 volcano-tectonic (rock fracture), 20 long-period (fluid flow), and 48 hybrid (mixed rock fracture and fluid flow) events. The swarm was accompanied by increased fumarolic activity at Sabancaya's summit. IGP scientists estimate 2.7 million cubic meters of magma were injected beneath the volcano during the swarm. IGP has an excellent webpage devoted to the activity (though not updated with new information since the swarm) from which a few diagrams are included here.
The Peruvian Civil Defense has called an orange alert for the volcano. Iy will be monitored 24 hours a day and will call the population to evacuate as soon as it is necessary. We have 2 video's below, 1 in Spanish (a longer one with some comment of the Civil Defense spokesman) and 1 English one from Reuters.
We will of course keep an eye on what happens in Peru and will Update this article if necessary. Certainly : To Be Continued ...
KVERT reports no significant changes in eruptive behavior at the six active Kamchatkan volcanoes during the past 24 hours. Seismicity has increased slightly (from weak to moderate level) at both Sheveluch and Karymsky volcanoes. Recent MODIS satellite thermal imagery reveals a multi-pixel "hotspot" at Tolbachik volcano again today.
Small local earthquakes continue at Mammoth Mountain volcano (CA) (station MRD). Most of the seismicity occurred in a burst yesterday morning. Diagrams illustrating event locations were updated later yesterday. A time-vs-depth diagram shows a "channeling" pattern (likely from vertical movement of fluids along fractures) between 3 km and 7 km depth beneath the edifice. A few deep low-frequency events (12 km - 20 km depth) continue beneath Mammoth mountain as well.
Frequent explosions continue at Colima volcano (Mexico). Exhalations (mainly of gas) now occur at an average rate of about two times an hour at Popocatepetl volcano. The Popo seismogram shows low-level volcanic tremor, exhalation signals, and small local and regional earthquakes.
INSIVUMEH reports that small strombolian explosions continue at Pacaya volcano. Seismograms recorded at the volcano (station PCG) now show only very low-level tremor. Moderate-sized strombolian explosions deposit fine ash as far as 10 km from Fuego volcano (explosions are reported to heard up to 7 km away from Fuego). Fuego seismograms (station FG3) indeed show the volcano to be more "animated" than we've seen recently. Vulcanian explosions lift ash as high as 3300 meters at the Santiaguito Dome Complex (Santa Maria volcano). Today ashfall from Santiaguito affects the Palajunoj region. Increased lava extrusion is generating samll pyrocalstic flows from the snout of a lava flow descending the dome. Recent MODIS satellite thermal imagery shows a bright "hotspot" associated with the renewed lava extrusion.
Tiny local earthquakes rattle Nevado Del Ruiz (station OLLZ) and nearby Machin (station CIMA) volcanoes again today.
Volcanic tremor and small earthquakes have increased slightly at White Island volcano (New Zealand) overnight. This morning's volcanocam view of the White Island crater floor shows strong steaming from the vent.
Recent OMI satellite imagery shows an enhanced SO2 plumes issuing from Nevado Del Ruiz, Poas (?) (Costa Rica), and Etna (Italy) volcanoes, with relatively weak plumes drifting from Popocatepetl, Nyiragongo (DRC), and Ambrym (Vanuatu) volcanoes. MODIS satellite thermal imagery also detected a "hotspot" at Popocatepetl volcano.