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. -
March 13, 2013 volcano activity
KVERT reports no significant changes in eruptive behavior of the six active Kamchatkan volcanoes: Tolbachik, Kliuchevskoi, Bezymianny, Sheveluch, Kizimen and Karymsky. Amplitude of volcanic tremor has diminished overnight at Tolbachik after being slightly elevated through this past weekend. Seismicity is sustained at a moderate level at Gorely volcano in-conjunction with strong hydrothermal activity occurring within and around the volcano's crater lake.
Small, shallow earthquakes continue to be frequent at Iliamna volcano (Alaska Range) (station INE).
Small earthquakes, a few strong enough to be located, also continue at Mount Hood volcano (OR) (station TDH).
A few deep (10 km - 20 km depth) low-frequency earthquakes (indicative of magma movement) have occurred the past week near (immediately west of) Lassen Peak volcano (CA). These type of events are not unusual at Lassen Peak, but they are scientifically interesting.
A few deep low-frequency events (beneath the west flank of Mammoth Mountain volcano) contribute to the scattered earthquake activity along the southern boundary of Long Valley Caldera (CA) (station MRD) during the past 24 hours.
Volcanic earthquakes, explosions and rockfalls have become very frequent at Colima volcano (Mexico) in the past few days. Exhalations of gas, occasionally mixed with volcanic ash, now occur an average of just less than once per hour at Popocatepetl volcano. A few volcanic earthquakes are visible (within low-level volcanic tremor) on the current Popo seismogram. Wind "noise" affects the early part of the record.
Pacaya volcano (Guatemala) continues to emit fine non-juvenile volcanic ash during short, enhanced degassing events now occurring within MacKenney Crater. Occasional moderate strombolian explosions continue at Fuego volcano, deposting fine volcanic ash as far as 10 km from the volcano's summit. Three moderate vulcanic explosions occurred through this morning at Santiaguito Dome Complex (Santa Maria volcano). Rockfalls and occasional small pyroclastic flows also occur from the fronts of four active lava flows descending the Caliente dome. Two points of continuous incandescence were observed overnight on opposite sides of the dome (east and west). Fine volcanic ash drifting from Santiaguito was deposited on Faro and La Florida villages during the past 24 hours. No seismic data were available from INSIVUMEH again today.
The tempo of volcanic earthquakes has increased overnight at San Cristobal volcano (Nicaragua) (station CRIN). Another episode (explosion?) of strong harmonic tremor struck Concepcion (station CONN) in the past 24 hours. Pulses of elevated volcanic tremor continue at the volcano, but volcanic earthquakes (normally frequent at the volcano) have virtually disappeared from seismic records the past two days. Small volcano-tectoninc events are apparent on the most recent (incomplete due to equipment malfunction) Concepcion seismogram. Volcano-tectonic earthquakes remain frequent at Telica volcano (station TELN), occurring in mini-crises on a daily basis this past week.
Stronger volcanic earthquakes, while continuing, appear to be lessening in rate of occurrence at San Miguel volcano (El Salvador) (station VSM) the past two days. Electronic telemetry interference affects the record.
After being elevated and sustained since Friday, volcanic tremor at Nevado Del Ruiz volcano (Colombia) (station OLLZ) has returned to "background" level. An volcano-tectonic earthquake swarm (of over 260 events) appears to be winding-down at Galeras volcano (station CUVZ). Small (ash?) emission event signals are also apparent on recent Galeras seismograms.
Co-eruptive seismicity is declining at Tungurahua volcano (Ecuador) (station RETU) and unstable at Reventador volcano (station CONE). Small earthquakes have increased slightly the past few days at Cotopaxi volcano (station CO1V).
IGP reports that seismicity remains elevated at Sabancaya volcano (Peru). In-particular, long-period (volcanic) seismicity increased between the end of February and the first week of March 2013. Numbers of long-period earthquakes at the volcano have declined over the past week. The most recent report on activity at Sabancaya is available on the Instituto Geofisico del Peru website. It includes a recent seismogram and a photo of continuing fumarolic activity at the volcano's summit.
The level of volcanic tremor at White Island volcano now resembles that occurring at the volcano before the recent period of unrest began last year. As such, I will not report on White Island volcano from now-on unless there is a significant change in the level of volcanic activity there.
Recent OMI satellite data show a significant SO2-enriched plume drifting from Nevado Del Ruiz volcano. A similar-sized plume is visible drifting from Nyiragongo volcano (DRC). MODIS satellite thermal was not updated again today.