And an eruption in the early morning hours (0409am) for about 10 minutes - it was preceded by a strong pulse at 2222 PM last evening.
There is some very slight slow wave (magma movement), but no apparent rock breakage signatures appearing.
And an eruption in the early morning hours (0409am) for about 10 minutes - it was preceded by a strong pulse at 2222 PM last evening.
There is some very slight slow wave (magma movement), but no apparent rock breakage signatures appearing.
Last edited by Bob; 29th September 2016 at 06:49.
Another eruption event at Tungurahua today in the morning:
prior to the eruption were spikey rock breaking signatures.
Tungurahua this evening let off a large brief 1 minute blast, but did not continue with a full fledged eruption (ATM)..
It is clearly active again, but the potential upcoming events are not yet fully obvious.
Early in the morning about 45 minutes of an eruption happened at the volcano. There was no warning, such as slow-wave, or strong pulse or double-pulse like events prior. Afterwards there was about 15 minutes of strong rock breakage spikes showing up. That diminished to calm when suddenly there were two very large impulses about 0700 and 0701. Worth keeping an eye on this morning.
==update==
eruptive activity was noted briefly at about 1120 local time and about 2 pm local time.
Last edited by Bob; 24th September 2016 at 19:23.
Tungurahua is continuing to rumble through the night -
It appears that Tungurahua has woken up again and is in an eruption cycle. If it increases or decreases we shall see. During the late night, a 6 minute low level sustained event about 2313 local time was followed by the signature "double pulse" events that Tungurahua has been noted to present. Keeping an eye on things.
Notice from the Geophysical Institute, Ecuador - re: Tungurahua's awakening
Interpretation
Volcanic rise of land (inflationary trend), indicating magmatic activity below.
In the last 8 years of activity Tungurahua volcano has had 15 similar quiet periods to the current period with low seismic activity, deformation inflationary trend, and surface activity characterized by low energy fumaroles.
Mostly these quiet periods were followed by small eruptions (Volcanic Explosivity Index IEV 0-1 with principal phenomenon ash falls) and sometimes by larger eruptions (IEV 2 pyroclastic flows). It is important to note that the vast majority (80%) of these eruptions had no premonitory signs of recovery in the short term (hours to days).
The actual deformation of the volcano is evidence of magmatic intrusion (movement of magma from a deeper reservoir) has been observed on many occasions before the eruptions of Tungurahua.
The low outgassing could indicate a blockage of the duct that prevents the free passage of magmatic gases. Given that the current quiet period had exceeded six months (185 days) and the sharp increase in seismic activity (LP since 12/09, from 16/09 tremor, and the swarm of LP 18/09) is It estimates that a (large eruption) in the short term (next few days to weeks) is possible.
Eruptive scenarios
Based on the results obtained from volcanic monitoring and the recent history of reactivations of Tungurahua two eruptive scenarios that could occur in the short term (next few days to weeks) is proposed:
1) Reactivation fast. During this stage of Vulcan style at the beginning of the eruptive phase or after a few days, it could produce a rapid opening of the duct with moderate explosions at large (eg. In May 2010, July 2013, April 2014). This scenario could be a large eruption column (up to 10 km above the crater) and pyroclastic flows that could descend the gorges to reach the foot of the volcano.
The falls of ash and rubble associated with this type of high eruptive column are more likely to affect areas farther from the volcano with more variable directions due to the variability of the wind direction at this point. Ballistic missiles (blocks and volcanic bombs) associated with explosions could reach a distance of 5 km from the crater.
In this scenario small lava flows could decline by the Northwest flank with a range of less than 4 km. side lahars could be generated due to the remobilization of eruptive material by rain and could cut the road Baños-Penipe. Depending on the amount of material accumulated in the streams and the intensity / duration of rain these lahars could be small to moderate.
This is the most likely scenario eruptive due to the absence of emissions of gas, which would indicate a closed conduit.
2) gradual reactivation. During this stage Strombolian style, which can last from several weeks to a few months, we could see small to moderate explosions, lava fountains and continue columns of ash less than 6 km above the crater (eg. April-May 2011 , March 2013, April 2015).
The main phenomenon is the ash falls, moderate to strong, which primarily affect the west of the volcano (unless a change in wind direction is observed).
Ballistic missiles (blocks and volcanic bombs) and small pyroclastic flows could reach a distance of 2.5 km from the crater. Small secondary lahars could be due to the remobilization of eruptive material by rain and could block the road Baños-Penipe.
It is important to note that volcanic eruptions are of an unpredictable nature and the activity of the volcano can also return to normal without eruption.
These settings can be changed according to changes in the activity of the volcano and analysis of data from the instrumental and visual monitoring. The IGEPN maintains constant vigilance in the center Terras (Quito) and Tungurahua Volcano Observatory.
Continue to watch the seismograph recorder throughout the night - events are continuing
The double pulses are still present, plus very small rock breakage patterns - in Post #227 above, the Geophysical Institute was warning of a potential for "rapid" relief of the magma with an explosive release (scenario 1) as being likely, with no strong warnings showing up on the seismiographic recorders. What is being noted is the double pulse pattern, explosive "releases" (not too large currently), and numerous very low level rock fractures. That could very well indicate that there is a "frozen plug" in place in the magmatic plumbing system. It could be assumed if there is a strong regional seismic quake, that the impulse may shake enough of the plumbing system to allow for a pressure relief to happen (eruption).