This (almost) daily post intends to follow up the activity changes of volcanoes all over the world.
This post is written by geologist Richard 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. -
June 28, 2012 volcano activity
Intense volcanic seismicity continues to rattle El Hierro today. Deformation monitors (GPS) are beginning to show inflation as well.
Interesting small repeating earthquakes at regular intervals are occurring at Galeras volcano (Colombia) today (station ANGV). Such earthquakes are observed on volcanoes from time to time, though more frequently at glaciated ones. Galeras is barren of glacial ice.
Activity at Nevado del Ruiz (Colombia) remains staid with low level tremor, but the volcano continues to emit tons of SO2 per day.
Tungurahua volcano (Ecuador) still exhibits unrest from an outburst yesterday (station RETU)
Small volcano-tectonic earthquakes affect Popocatepetl (Mexico) along with occasional volcanic tremor. Minor gas and ash eruptions are continuing daily.
In Alaska, a magnitude M2.0 shallow earthquake and a 13 km deep (low-frequency?) earthquake struck Iliamna volcano today. That volcano was placed in “Yellow” alert level by the U.S.G.S. Alaska Volcano Observatory early this year due to increased earthquake activity, heat and gas emission.
At nearby Spurr volcano, small earthquakes are becoming apparent on seismograms there. That volcano experienced a debris flow several days ago.
A single, scientifically interesting earthquake occurred yesterday at Newberry volcano (Oregon) earlier today. The earthquake appears to have occurred along a caldera ring fault and exhibits low-frequency characteristics, which can signify fluid movement. The lower frequency content can also be an artifact of the events shallow depth and the passage of seismic energy through soft sediments within and near the caldera. A new seismic network was installed at the volcano earlier this year and will probably record many similar events in coming years as part of the volcano’s “routine” background activity.
Infrared imagery from the Metop satellite showed a possible rising steam plume from the area of Siple volcano (Antarctica) on 20 June. The imagery, as interpreted by Mark Drapes, indicated that the volcano was about -22 degrees Celsius, about 6 degrees warmer that the surrounding landscape, and the base of the plume was about -55 degrees Celsius.