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LithiaWx

Mount Agung volcano

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The Ministry of ESDM Geological Agency of Volcanology and Geological Hazard Mitigation released a detailed report about Mount Agung today. The wonderful Dr. Krippner translated. Posting below for posterity:

Quote
1/n * Monitoring Data Analysis *
-Visual-
After undergoing a volcanic earthquake swarm over the period Sept-Oct 2017, finally on 21 November 2017 at 17:05 WITA the phase of eruption of Mount Agung evolved to produce volcanic ash as high as 700 m above the peak.

2/n After the eruption, the next eruption occurred again on November 25, 2017 at 17:20 WITA with an ash plume height of 1500 m above the peak. On 26 and 27 November 2017 eruptions occurred with the ash column height reaching 3000 m above the peak.

3/n On 28 November 2017 the eruption produced an ash column reaching 4000 m above the peak. On November 29, 2017 the eruption produced an ash column height reaching 2000 m above the peak.

4/n At night, incl. tonight, there is incandescence that emanates from the crater. The observation of the incandescence above the crater is possible due to the presence of high-temperature lava in the crater. This is reflected in the ash/steam plumes causing it to be observed.

5/n Lahars have occurred & mainly flowed in the rivers in the Sthrn sector, incl. Tukad Yehsa, Tukad Sabuh & Tukad Beliaung & in the Nthrn sector in Tukad Bara. The lahars did not result in casualties, however, lahars have impacted several houses, roads and rice fields.

6/n
- Seismicity -

Earthquakes are still dominated by the occurrence of deep and shallow volcanic earthquakes. This indicates that there is still magma movement at depth. Currently the number of volcanic earthquakes is no longer as much as the period September-October 2017.

7/n This happens because the magma path to the surface is now more open. Therefore, although the number is not much, but it does not mean that volcanic activity has subsided.

8/n Continuous tremors with amplitudes over the background level, until overscale (beyond the capability of recording devices) continue to be recorded since November 28, 2017 to today (December 1, 2017). This indicates a high intensity of activity near the surface.

9/n Low-frequency earthquakes are recorded several times and this is related to the movement of Magmatic fluid to the surface.

10/n - Deformation -
GPS measurement results do not record a clear pattern of inflation ahead of the eruption. This is different from the pattern shown by GPS prior to the occurrence of swarms (sequence of volcanic earthquakes) in the period September-October 2017...

11/n
... whereas that GPS showed inflation of the body of Mount Agung [slight outward moving of the volcanic flanks] since August 2017 until mid-September 2017.

12/n The pattern shown by the tiltmeter measurements is in the form of inflation before eruption and deflation after eruption takes place.
[tiltmeter general info here: https://t.co/gjhw9XqUv7]

13/n - Geochemistry -
Lab test results of the volcanic ash produced by the opening eruption on November 21, 2017 show the existence of juvenile content (new magma material). Within the ash, older material from the 1963 eruption was also identified...

14/n
... Based on the results of this laboratory test, it can be concluded that the first eruption of Gunung Agung was phreatomagmatic. This eruption can occur when the new magma interacts with water in the aquifer system under the crater of Mount Agung.

15/n
Prior to the Nov 21, 2017 eruption, CO2 gas could be measured at high concentrations by the MultiGAS equipment flown by Drone. However, the SO2 gas concentration was not yet measurable. After the Nov 21, 2017 eruption, to this day...

16/n
... the concentration of SO2 gas is still consistently measured. Higher concentrations of SO2 was observed over the period of 26-27 November 2017, after which, the concentration of SO2 relatively decreased.

17/n - Remote Sensing Satellite -

Satellite data consistently records hotspots [higher heat output] on 27, 28 and 29 November 2017 with temperatures ranging from 286.6-298.8 +/- 6 degrees Celsius, with a maximum power of 97 megawatts.

18/n
Satellite data also indicate that the effusive eruption (lava flow to the surface) is still occurring within the crater.

19/n

This effusive eruption has implications for the addition of lava volume in the crater with an estimated current lava volume of about 20 million cubic meters, or one third of the total volume of the crater.

20/n * Conclusions*
Based on multi-parameter data analysis, it can be concluded that until now (December 1, 2017) volcanic activity of Agung is still high and still in the phase of eruption.

21/n
Therefore, the status of Agung is still at Level IV (Awas). Communities around Agung and climbers/visitors/travelers are urged to NOT climb Agung and not to engage in any activity within the Danger Zone...

22/n
... within the area of the Agung crater and in all areas within a radius of 8 km from the Agung crater, plus the sectoral expansion to the North-Northeast and Southeast-South-Southwest out to 10 km from the Crater of Mount Agung.

23/n
It is still safe to travel in Bali as long as you do not enter the above Danger Zone.

Ministry of ESDM
Geological Agency of Volcanology and Geological Hazard Mitigation
--END--
https://t.co/jC4a8Hjn0r

 

 

 

 

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It is interesting that the eruption has transitioned to effusive in a matter of days. Agung has a pretty large 1 km wide crater that is already being reported as 1/3 full of new lava. If this trend continues, we may have a flow down the flanks of the volcano from the lower rim within a week or two. I presume that flow would be andesite. But that is speculation. It will have to be sampled.

 

Edit: I am not entirely sure about that explanation on volume. I am uncertain if the ministry is reporting that the total erupted volume for the event cycle's entirety is 20 million cubic meters (one-third volume of crater) or that incandescent dome or lava flow within the crater is now 20M m3 (one-third volume of crater). Perhaps they will clarify that soon.

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Per my previous comments, looks like the ministry was referring to volume in the crater as actual effusive lava.

The official release is now in English. I will post that as the site is slow to load.

MAGMA Indonesia

Update on the Volcanic Activity of Mount Agung (1 December 2017 21:00 localtime GMT+8)

2 December 2017 08:35 WIB, Ir. Kasbani, M.Sc.

The following update is based on multiple volcano monitoring parameters:

A. Analysis of monitoring data

Visual observations

After experiencing a swarm (series) of volcanic earthquakes during September and October 2017, on November 21, 2017 on at 17:05 WITA an eruption began at Mount Agung, Bali (elevation 3031 m or 9944 ft.). This eruption produced volcanic ash and gas that rose to heights of 700 m (2300 ft.) above the summit (12,000 ft. above sea level (ASL). Based on observations from the CVGHM Observatory Post stations, over the following week, the height of ash columns increased as follows: 25 November, 2017, 17:20, 1500 m above the summit (15,000 ft. ASL); 26 and 27 November 2017, 3000 m (20,000 ft. ASL), 28 November 2017, 4000 m (23,000 ft. ASL). Higher maximum altitudes (ASL) of the plumes were reported at times by the Darwin Volcanic Ash Advisory Center because they take into account clouds that contain ash that have drifted downwind from the volcano. CVGHMs ground-based observations estimate the ash cloud height by only measuring the vertically driven plume that contains ash (before the ash is dispersed). Then on 29 November 2017, the ash column height decreased to 2000 m above the summit (16,000 ft. ASL). These ash columns were gray in color and produced ash-fall in downwind areas. Since 30 November 2017 and continuing until today, the observed the column has been white in color and has had a maximum height of 2000 m above the summit (16,000 ft. ASL).Since the eruption began and continuing until today, red glow has been observed coming from the summit crater of Mount Agung. We attribute the red glow to the presence of high temperature lava in the crater. The red glow from the lava in the crater shines on the rising column of ash and steam and gives the lower part of the ash column a red color.Lahars have taken place since the ash eruptions began on 21 November. They have flowed down from the summit along rivers in in the southern sector of the volcano, including Tukad Yehsa, Tukad Sabuh and Tukad Beliaung as well as in the northern sector including Tukad Bara. These lahars have not resulted in fatalities. However, lahars have impacted houses, roads and agricultural areas.

Seismic

High-frequency volcanic earthquakes continue at Mount Agung, and include both shallow (and proximal) and distal types, although the occurrence rate has decreased compared to September- October 2017. The decrease in number of volcanic earthquakes is attributed to the fact that a more open pathway for magma to rise to the surface is now present. However, high-frequency earthquakes continue to occur and show that the volcano is very active and capable of pressurization to cause the ongoing eruptions.Continuous seismic tremor has taken place from 28 November 2017 through today (December 1 , 2017). Amplitude of the tremor has ranged from just above the background levels of the CVGHM seismic network to over-scale (i.e., exceeding the recording limits of the instruments used). The tremor is a result of the ongoing gas and ash eruptions through the summit crater.Low frequency earthquakes have also taken place and are attributed to movement of magmatic fluids as they rise to and are erupted at the surface.

Deformation 

Data from the GPS network did not show significant changes prior to the eruptions on November 21 and Nov. 25. In August and September, there had been several centimeters of inflation that likely was caused by accumulation of magma beneath the volcano. In addition, tiltmeter data showed inflation before the eruption began and deflation during the eruption, as is common at other volcanoes.

Geochemistry

Laboratory analysis of ash from the initial eruption of 21 November 2017 show the existence of juvenile fragments (i.e., from new magma) as well as fragments of old lava from deposits below the vent, such as those formed during the 1963 eruption and before. Consequently, we conclude that the initial eruption on 21 November 2017 was phreatomagmatic (i.e., that it took place when the new 2017 magma interacted with groundwater below the crater.Before the eruption of 21 November 2017, CO2 gas was measured at a high concentrations by MultiGAS equipment flown using a drone. However, very little SO2 gas was detected until after the November 21, 2017 eruption. Measurements of SO2 gas were highest during 26-27 November 2017; the concentration of SO2 has decreased somewhat since that time. These data are consistent with magma rising from great depth during the extended period of seismic unrest and reaching the summit crater of Mount Agung by the time of the 21 November eruption.

Satellie remote sensing

Satellite data also indicate that eruption of lava is ongoing within the summit crater. These data have recorded high temperatures consistent with new lava within the crater on 27, 28 and 29 November 2017. The volume of lava in the crater is currently about 20 million cubic meters, equivalent to about a third of the total crater volume.Satellite data have recorded a hot area within the crater on 27, 28 and 29 November 2017 with temperature ranges estimated at about 300 degrees Celsius. Because of technical considerations, these are regarded as minimum temperatures. The lava in the crater is much hotter, likely in the range 900-1200 degrees Celsius, based on comparison to lava from the 1963 eruption of Mount Agung.

B. Conclusions

Based on multi-parameter data analysis and as of this date (1 December 2017 WITS) we conclude that volcanic activity at Mount Agung is still high. This is an ongoing eruption. Consequently, the Alert Level remains at Level IV (Awas). Communities around Mount Agung as well as climbers / visitors / tourists are advised to not climb or conduct any activity in the Hazard Zone, namely in the area of the crater of Mount Agung and at a radius of 10 km in sectors to the the north and northeast and southeast, south and southwest of the crater. An 8 km radius from the summit also applies to all other areas. For details of hazard areas please refer to the map at: Provide link to hazard map with sectors shown here!_. This is a dynamic situation and the nature and extent of the Hazard Zone may be changed at any time.It is still considered safe for traveling in Bali outside of the Hazard Zone as described above.

Ministry of Energy and Mineral Resources
Geological Agency
Center for Volcanology and Geological Hazard Mitigation


https://magma.vsi.esdm.go.id/press/view.php?id=117

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Agung looks like a pressure cooker this morning. Really anxious for CVMPG to get a drone in the air while ash emissions are low/negligible to get a visual of the crater floor.

 

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Found the source from the image posted previously. Decided better to delete that and link the source to credit the photographer. It is gorgeous. The image was from sunset the night of Nov 30th and shared via the Associated Press. There was a light ash emission with pressure plume at the time of capture.

 

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1 hour ago, Windspeed said:

Agung looks like a pressure cooker this morning. Really anxious for CVMPG to get a drone in the air while ash emissions are low/negligible to get a visual of the crater floor.

 

 

Sounds like it's waiting to vent all of it's issues....seems passive aggressive at the moment! :lol:

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1 hour ago, IntenseBlizzard2014 said:

There's a plug in the volcano? Oh no. 

Sounds like that increases the likelihood of a larger eruption! If I read this correctly...seems like it's gonna have to come out somewhere, lol (but of course that's just my completely untrained opinion!)

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Mount Sinabung in Sumatra had a rather large eruption today. The dome that had been growing for several years appears to have collapsed, causing a rapid depressurization of magma. A large pyroclastic flow looks to have incinerated much of the exclusion zone, perhaps even areas beyond. The ash column may have reached over 9 miles (15 km) in altitude.

 

 

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6 minutes ago, Windspeed said:

Mount Sinabung in Sumatra had a rather large eruption today. The dome that had been growing for several years appears to have collapsed, causing a rapid depressurization of magma. A large pyroclastic flow looks to have incinerated much of the exclusion zone, perhaps even areas beyond. The ash column may have reached over 9 miles (15 km) in altitude.

 

 

 

What VIE level was it?

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A lot of these volcanic mountains have pretty high summits, so an explosion that sends SO2 up even 25,000 above the summit is really 33,000 feet above sea level. There are reports of anywhere from 15,000 to 55,000 feet above sea level for the ash cloud. Can't really tell which are right.

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Probably too early to know even if the PVMBG wanted to give an estimate. They will need to survey the area and deposit. Also, after checking VAAC, it also looks like the original 15 km altitude was an overestimate that was later revised to 8km. But that may still be incorrect. We'll need to await an official statement from the observatory there to get an approximation on VEI. But based on the size of the blast, I would not be surprised if was a VEI-4.

 

Edit: https://m.facebook.com/nextquake/videos/2466248543599446/

 

Edit 2: Sinabung in Indonesia Produces Largest Explosion Yet

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Will be interesting to see if the explosion on 2/19 is it, or if it continues. Discovery is saying the plume only got to 15,000 - 20,000 feet up despite initial estimates up to 55,000.

http://blogs.discovermagazine.com/rockyplanet/2018/02/19/sinabungs-massive-explosion-seen-from-space/#more-2251361

Even with the relative size of the eruption, there is no chance this causes any climate impact. The initial estimates of sulfur released are too low to cause much atmosphere effects and the height of the plume wasn’t tall enough to reach the stratosphere. Current estimates of the ash plume are between 5-7 kilometers, so between 16,000-20,000 feet (down from the initial guesses of over 50,000 feet).

The massive ash column from the eruption of Sinabung on February 19, 2018.

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