Tungurahua volcano news & eruption updates:
Tungurahua volcano, Ecuador: activity remains at a high level
Monday Dec 17, 2012 09:58 AM | BY: T
Explosion with pyroclastic flows down at 05:53 (local time) on 16 December. Source M. Yepez (IGEPN)
Current seismic recording (PAT1 station)
Following the first explosion on Friday, the volcano has entered a second violent phase of activity on Sunday. Numerous explosions have occurred in the morning of Sunday with ash rising up to 8 km above the crater. Small pyroclastic flows have descended the flanks and partly heavy ash fall has been affecting nearby areas. Combined with rainfall the fresh ash deposits have a dangerous potential to generate lahars in drainages surrounding the volcano.
Seismic spectrum from PAT1 station
Inflation of the volcano since 9 Dec confirms that a new magmatic intrusion has been taking place. Seismic and ash emission activity decreased during Sunday afternoon, but seismic activity remains at fluctuation moderate to high levels. New explosions and ash emissions could follow.
This is an abbreviated translation of the latest IG report from yesterday evening:
Sunday at 05h20 (local time), an explosion generated a 2 km tall ash column and was followed by 3 blasts, at 05h48, 05h53 and 06h02 (local time), generating an ash column that reached 7 km above the crater.
Lightning was observed inside the eruptioin column.
The explosion of 05h52 (local time) generated a strong gun-shot sound and shock wave that broke the windows of the church in Cusua.
Until 07h35 (local time) seismic activity was low and there were no emissions. This calm period ended with an explosion that generated a constant ash column that has been sustained until the end of this newsletter.
At 10h07 and 10h57 (local time) there were 2 small explosions.
During the first explosions (about 6 in the morning) and from 10h07 (local time) in the morning pyroclastic flows were generated that descended to the middle of the cone, through the streams of Achupashal, Mapayacu and Choglontús. With the explosion of 10h57 (local time) pyroclastic flows occurred which were restricted to the top of the volcano.
Associated with that activity there have been reports of falling gravel and small rock fragments in the sectors of CUSU, Cotaló, Pondoa, Runtún and Pillate. Thick ashfall affected the Banos sectors, Vascún, Agoyán and Ulba. Medium and fine ashfall occurred in the sectors of Palitahua, Choglontús, Manzano, Capil, Guadalupe Cevallos, Tisaleo, Ambato, Patate, Píllaro, Pelileo, Salcedo, and Pujilí Latacunga. During the afternoon today, slight ashfall was reported in areas located east of the volcano, as Green River, Black River, Palora, Mera, Arosemena Tola and Puyo.
Emission column heights during the morning and evening varied between 2 and 3 km above the crater and were drifting to the NW and NE.
The size of the explosions are classified as small to large, with the largest explosions recorded at 05h53 (local time) and the explosion of 6h02 ( local time). Periods of tremor with greater energy release and amplitude were recorded from 06h03 to 06h08 (local time), 07h34 to 07h37 (local time), 10h28 to 10h03 (local time), 10h14 to 12h30 (local time), 13h00 to 13h50 ( local time), 14h30 to 14h58 (local time). All explosions were accompanied by heavy cannon-shot noises and constant rumbling of moderate to high intensity.
Additionally, the deformation network indicates continuous inflation from December 9.
Based on the above, it is confirmed that this eruptive process is associated with a new volcanic intrusion. This process began with the explosion of 14 December at 14h35 (local time), and after a pause similar to that observed in other times, restarted the second phase of the eruptive process, Sun 16 December at 05h20 (local time) .
At the end of this newsletter, it is observed that the emission has decreased in energy and ash content. Also, seismic activity has decreased in energy release with respect to the registration for this morning, but still remains a level considered high. Therefore, and although in the last 6 hours there is a tendency of decreasing eruptive activity, is not excluded that more explosions and ash emissions that may be accompanied by pyroclastic flows might occur.
Links / Sources:
Links / Sources:
Friday, Dec 14, 2012
A sudden strong ash explosion occurred at Tungurahua volcano in Ecuador today at 14:35 local time. According to local reports, the eruption produced an ash plume rising to 6 km altitude and was visible from Ambato, Riobamba, Pelileo and Patate. The explosion followed an increase in seismicity over the past days. [more]
Friday, Dec 14, 2012
Numerous small volcanic earthquakes have recently been occurring at Tungurahua volcano. According to Earthquake-report, these likely reflect input of new (hotter) volcanic fluids beneath the cone. [more]
Wednesday, Oct 03, 2012
Activity remains low at the volcano which is almost constantly covered in clouds. ... [more]
Monday, Oct 01, 2012
Seismicity at the volcano remains moderate to low. Direct observations of summit activity are hindered by near constant cloud cover, but there are no indications of recent explosions or ash emissions. [more]
Wednesday, Sep 26, 2012
Visual observations are near impossible due to constant cloud cover, but the seismic activity, described as moderate by IG, does not indicate significant eruptive activity. [more]