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 1, 2013 volcano activity
KVERT reports no notable changes in activity at any of the Kamchatkan volcanoes today. Volcanic tremor remains high, though reduced in amplitude from previous weeks, at Plosky Tolbachik. Moderate seismicity accompanies lava extrusion at Sheveluch and Kizimen volcanoes. Low seismicity accompanies occasional explosive (Strombolian to Vulcanian) activity at Karymsky. Loud volcanic tremor eminating from Tolbachik masks seismicity that is likely taking place in-conjunction with lava extrusion at Bezymianny volcano and Strombolian activity at the summit of Kliuchevskoi volcano. Gorely volcano continues to exhibit moderate hydrothermal tremor and volcanic earthquakes in-conjunction with strong degassing.
After almost one month after having its aviation color code dropped from "yellow" to "green", along with as its alert level dropped from "advisory" to "normal", Iliamna volcano (Alaska Range) (station INE) is back at it with a fairly strong episode of earthquakes today. So far, the largest event recorded during the current pulse of seismicity measures a sizeable M3.1 with two other events in the M2.5-M3.0 bracket. Small local earthquakes continue to affect Tanaga (Aleutian arc) (station TASE) and Mount Spurr (Alaska Range) (station CKT) volcanoes.
Small earthquakes continue at and around Mammoth Mountain volcano (CA) (station MMS) today.
Small explosions, rockfalls and occasional volcanic earthquakes continue at Colima volcano (Mexico), following Tuesday's relatively large explosion. The explosion effectively removed the lava dome which had slowly accumulated within (and overtopped in places!) the volcano's summit crater since the late 1990's.
Fresh lava is being extruded within the newly blasted-out crater, accompanied by harmonic tremor visible on today's Colima seismogram. Exhalations of gas and some ash continue to occur at an average of once per hour at Popocatpetl volcano. The Popocatepetl seismogram also shows low-level volcanic tremor today.
Seismic data for the Guatemalan volcanoes was not updated again today. MODIS satellite thermal imagery shows a multi-pixel "hotspot" at Fuego volcano. Whether this larger thermal anomaly reflects increased lava extrusion at the volcano or decreased cloud cover in relation to previous satellite transits is not clear. The Santiaguito (Santa Maria volcano) volcanocam offers an especially clear view of the dome complex today. Alas, the volcano is only steaming at low levels.
Volcanic tremor increased, becoming continuous at San Cristobal volcano (Nicaragua) (station CRIN) overnight. Volcanic tremor is also unsteady at nearby Masaya volcano (station MASN).
Occasional volcanic earthquakes continue to "pop-up" within continuous low-level volcanic tremor at San Miguel volcano (El Salvador) (station VSM).
Numerous small volcanic earthquakes afflict Nevado Del Ruiz volcano (Colombia) (station OLLZ) again today. Episodes of low-magnitude volcanic tremor have diminished at the Ruiz. Numerous small volcano-tectonic events which, judging by their P-S intervals, eminate from the deep (12-15 km depth), southeast "nest" of seismicity, emergent at Machin volcano (station CIMA) over the past several years. Numerous small earthquakes also affect Galeras volcano (station ANGV).
Numerous volcanic earthquakes and continuous low-level volcanic tremor rumble within Tungurahua volcano (Ecuador) (station RETU) again today. EPN personnel flew around Reventador volcano yesterday to document changes at the volcano. They reported numerous new lava flows extend down the flanks of the cone (and continue to be erupted), as well as continued explosive activity at the summit. Over 20 new lava flows have been emitted at the volcano since it violently awakenend in 2002. High levels of volcanic tremor, and both volcanic and explosion earthquakes testify to the continuing high levels of activity at the volcano (station CONE).
SERNAGEOMIN reports continued reduced activity at Copahue volcano (Chile-Argentina border), with low-level volcanic tremor and small degassing-related events occurring beneath the cone. No volcano-tectonic earthquakes (which typically accompany inflation of the edifice) were recorded during the past 24 hours.
Another round of hybrid earthquakes is affecting White Island volcano (New Zealand), along with continuous, "loud" volcanic tremor. An early morning volcanocam shot from the crater floor shows increased steaming at the volcano today. Seismicity remains low at nearby volcanoes Tongariro and Ruapehu.
Recent satellite imagery shows "hotspots" at Tolbachik (multi-pixel), Popocatepetl (single pixel), Fuego (multi-pixel), and Etna (Italy) (single pixel) where Strombolian activity resumed at the Bocca Nuova this past week. OMI SO2 sensors detected SO2-enriched plumes of various sizes drifting from Tolbachik, Popocatepetl, Nevado Del Ruiz, Copahue, Etna, Ruang and Merapi (Java), Langila (New Britain), as well as from one or more of several active Sangihe arc vents.