Volcano activity of July 15, 2012 - Karymsky, Katla, Popocatepetl, Fuego, Santa Maria, Pacaya, El Hierro, Cumbal, Galeras and Sotara

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. -

July 15, 2012 volcano activity

Interesting volcanic activity all over the place today!

Popocatepetl volcano, webcam image

In the Atlantic: Jon Frimann (Iceland Earthquake and Volcanoes Blog) reports a glacial outburst flood from Myrdalsjokull (the glacier covering Katla volcano). Katla has been experiencing its usual summer spat of seismic activity (an earthquake swarm occurred at the volcano just one week ago today), believed to be caused by hydraulic changes (glacial unloading and cold water input due to summer melting) within the underlying hydrothermal system. The outburst flood suggests some hot water has reached the surface beneath the icecap.

El Hierro (Spain) continues to wind-down from the past month's seismic crisis, although a magnitude M3.0 event occurred there late yesterday.

In the North Pacific: A slightly inhanced SO2 plume is situated over Karymsky volcano (Kamchatka Peninsula). Karymsky has experienced explosive (vulcanian) outbursts on a regular (daily) basis since at least the 1970's (the current eruptive period at the volcano began approximately 500 years ago!). The most recent KVERT report on the volcano notes diminished seismicity at the volcano over the past week.

In Mexico: Activity at Popocatepetl (our Featured Volcano) has also diminished to an average of one exhalation (of gas and some ash) per hour for the past 10 hours (in-concert with diminished seismic activity at the volcano).

In Guatemala: A recent NOAA satellite pass shows slightly enhanced SO2 over three volcanoes (Santa Maria, Fuego and Pacaya) we have watched. Rising tremor at Fuego suggests we should be on the lookout for another outburst (this week sometime?) similar to those which have struck from time to time the volcano this past year. Tremor also appears to be enhanced the past few days at Pacaya, so keep watching here to see how activity at this very active volcano progresses.
Santa Maria (station STG3) Fuego (station FG3) and Pacaya (station PCG)

In Colombia: While tremor at Nevado Del Ruiz volcano has dropped to very low levels (compare a current seismogram (station OLLE) with that of one month ago (station BISN)), SO2 continues to stream from its vent. SO2 is indicative of high temperature (active) magma at shallow depth. Very small earthquakes, visible on seismograms yesterday at Cumbal volcano have disappeared on today's records (station MEVN). A burst of larger amplitude low-frequency (caused by fluid movement) earthquakes occurred overnight at Sotara volcano. Activity appears to have diminished again there (station SOSO).