Tungurahua Volcano (Ecuador): volcanic activity decreases
Thursday Sep 13, 2012 12:05 PM | BY: T
After the sharp increase in volcanic gas emissions (SO2) and abundant presence of seismic signals related to internal movement of fluids recorded earlier this month of September, activity from Tungurahua volcano has declined markedly since 4 September and presently has seismicity with moderate to low levels, and occasionally some small steam emissions. A drastic reduction in SO2 emission rates recently is one of the most significant observations.
Tungurahua Volcano with little surface activity in the crater. In the crater was observed the presence of a non-permanent and weak plume of steam and gas rising about 100 meters high and moving westward. There have been no reports of ash fall, or noise and explosion sounds. Image taken on the afternoon of September 11, 2012. Source: IGEPN
Also, the deformation measurements stopped to show a tendency of gradual inflation, suggesting build-up of internal pressure and are now oscillating between in- and deflation, suggesting a drop in internal pressure.
There have been no explosions nor ash falls in the last week. Furthermore, nearly 2 weeks have passed since the last recorded volcano-tectonic earthquakes were felt in the area. There is no new evidence to suggest the possibility of ascent of new magma pulses as interpreted in the report No. 5 from 30 August.
The intense degassing of the first 4 days of September may have been caused by the intrusion that ended at the end of August. The current observations and parameters indicate a steady decline in pressure and very little activity on the surface.
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Wednesday, Sep 12, 2012
The volcano remains relatively quiet, but direct observations are difficult to cloud cover. The seismic signal is low with some weak tremor pulses. [more]
Tuesday, Sep 11, 2012
Volcanic earthquakes and weak intermittent tremor occur at Tungurahua volcano. There were no recent explosions. [more]
Monday, Sep 10, 2012
While seismic activity remains moderate with some volcanic tremor present, there is currently only steaming from the volcano. [more]
Saturday, Sep 08, 2012
The volcano produces a constant steam plume, but there were no recent explosions or reports of ash emissions. The tremor is low at the moment. [more]
Thursday, Sep 06, 2012
IG reported that during 29 August-4 September visual observations of Tungurahua were often limited due to cloud cover. Moderate seismicity was detected during 29-30 August and a few earthquakes were felt by residents. On 30 August steam plumes with low ash content rose 500 m above the crater and drifted W. ... [more]