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. -
May 4, 2013 volcano activity
KVERT reported no significant changes in eruptive/seismic beahvior at the five active Kamchatkan volcanoes: Tolbachik (basaltic fissure eruption - declining volcanic tremor), Sheveluch and Kizimen (lava flow/dome extrusion with occasional collapses/explosions - moderate seismicity), Bezymianny (lava flow/dome extrusion - weak seismicity), and Karymsky (occasional strombolian/vulcanian explosiosn - not seismically monitored due to equipment outtage). Gorely volcano continues to exhibit a moderate level of seismicity in-conjunction with strong hydrothermal activity within and around the crater lake there. Recent MODIS satellite imagery depicted multi-pixel thermal anomalies at both Tolbachik and Sheveluch volcanoes.
Numerous tiny seismic events (and small regional earthquakes) are taking place at/or near Korovin volcano (Aleutian arc) (station KOWE).
Two earthquakes occurred at Newberry volcano (Cascade Range) (station CPCO) yesterday morning. Since the events were only twelve seconds apart, their signatures resembled a regional earthquake (to me the first event appeared to be a P-wave and the second, larger, event resembled a typical S-wave arrival!), so I passed-over mentioning them in yesterday's report. The two events are interesting though, not only becasue of their close occurrence in time, but also because of the first being deeper than the second and also that the second earthquake (a magnitude M1.7) was the largest event recorded so far by the barely year old Newberry seismic network. Earthquakes were also recorded beneath the young Southern Oregon volcanoes west of Klamath Falls early today as well. The Oregon Cascades have been (unusually) seismically active the past month and perhaps it's no coincidence that a slow-slip event just ended (in April) along the subducted slab interface to the west (What I'm really saying is, I don't believe it's a coincidence!).
Still no seismic data from UCol pertaining to Colima volcano (Mexico). The Colima volcanocam has painted a tranquil scene at the volcano for most of the day. Activity is low at Popocatepetl volcano, with relatively small exhalations occurring an average of slightly more than once an hour today.
The Guatemalan volcanoes: Pacaya (station PCG), Fuego (station FG3), and Santa Maria (station STG3) show a fair amount of internal activity, but externally have displayed some self-control with limited gas and ash outbursts (at Fuego and Santiaguito) and minor strombolian explosions at Pacaya.
Volcanic earthquakes remain frequent at San Miguel (El Salvador) (station VSM).
Volcano-tectonic seismicity continues to be elevated at Nevado Del Ruiz volcano (Colombia) (station OLLZ). Gas and ash emission events are frequent today at Galeras volcano (station CUVZ). Tiny seismic events are visible on seismograms at Machin volcano again today (station CIMA).
Eruptive activity strengthened overnight at Tungurahua volcano (Ecuador) (station RETU), but has since waned. Co-eruptive seismicity is also high at Reventador volcano (station CONE). Small seismic events remain numerous at Cotopaxi volcano (CO1V). Recent MODIS satellite thermal imagery captured "hotspots" at Reventador and Sangay volcanoes, making a volcanic tri-fecta for Ecuador today!
Numerous tiny earthquakes punctuate continuous volcanic tremor at White Island volcano (New Zealand).
Recent OMI satellite imagery captured SO2-enriched plumes drifting from: Tolbachik, Popocatepetl, Turrialba (Costa Rica), Tungurahua, Nyiragongo (notable!), and Ambrym (Vanuatu) volcanoes today.