June 27 , 2017. EN. Cleveland , Bogoslof , Sheveluch , Reventador .

Home / Alaska / June 27 , 2017. EN. Cleveland , Bogoslof , Sheveluch , Reventador .

June 27 , 2017. EN. Cleveland , Bogoslof , Sheveluch , Reventador .

June 27 , 2017.

 

Cleveland , Alaska :

AVO/USGS Volcanic Activity Notice

Current Volcano Alert Level: ADVISORY
Previous Volcano Alert Level: WATCH
Current Aviation Color Code: YELLOW
Previous Aviation Color Code: ORANGE

Issued: Monday, June 26, 2017, 12:06 PM AKDT
Source: Alaska Volcano Observatory
Location: N 52 deg 49 min W 169 deg 56 min
Elevation: 5676 ft (1730 m)
Area: Aleutians

 

 

AVO Image

Volcanic Activity Summary:
Recent observations of Cleveland Volcano suggest that unrest has declined and it is unlikely that eruptive activity is continuing. Satellite observations have yielded no evidence for continuing lava effusion and there have been no detections of anomalous seismicity or infrasound from the volcano since a brief explosion on Tuesday evening (May 16) at 19:17 AKDT (03:17 May 17 UTC). Evidence for lava effusion in the summit crater was observed in satellite data on June 7, but since then observed surface temperatures have become weaker, suggesting that lava effusion has paused or ended.

The overall decline in unrest and lack of evidence for lava effusion warrants downgrading the Aviation Color Code to YELLOW and the Volcano Alert Level to ADVISORY.

Recent Observations:
[Volcanic cloud height] N/A
[Other volcanic cloud information] N/A

Remarks:
Cleveland volcano is not monitored with a full real-time seismic network and this inhibits AVO’s ability to detect unrest that may lead to future activity. We are able to detect explosive activity using infrasound and limited seismic instruments on the island.

 

Source : AVO.

Photo : Werner, Cindy

 

Bogoslof , Alaska :

AVO/USGS Volcanic Activity Notice

 

Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

Issued: Monday, June 26, 2017, 6:48 PM AKDT
Source: Alaska Volcano Observatory
Location: N 53 deg 55 min W 168 deg 2 min
Elevation: 492 ft (150 m)
Area: Aleutians

Volcanic Activity Summary:
Seismicity for the eruption at Bogoslof volcano at 00:45 UTC on June 27 (16:45 AKDT on June 26) remained elevated until 00:59 UTC (16:59 AKDT) and has since declined to background levels. The eruption produced a volcanic cloud moving northeast with an estimated altitude of 25,000 ft asl by satellite data, and a pilot reported a visible cloud at 22,000 ft asl. Given the lower altitude of the volcanic cloud and short duration of the explosion, the Aviation Color Code remains ORANGE and Volcano Alert Level WATCH.

 

AVO Image

Bogoslof seen from Alaska Airlines flight from Adak to Anchorage on 6/22.

Recent eruptive episodes have produced multiple short-duration explosions interspersed with minutes to hours of inactivity between events, and future explosions could occur with little to no warning. AVO will continue to monitor seismic and infrasound data from nearby islands, as well as lightning data from the World Wide Lightning Location Network for signs of renewed activity.

Recent Observations:
[Volcanic cloud height] 25,000 ft asl estimated by satellite & pilot report
[Other volcanic cloud information] Cloud moving towards northeast
[Lava flow/dome] N/A
[Lava flow] N/A

Remarks:
The SIGMET warning message for aviation, issued by the National Weather Service Alaska Aviation Weather Unit currently is in effect up to 25,000 ft above sea level.

Source : AVO.

Photo : Read, Cyrus.

 

Sheveluch , Kamchatka :

VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)

Issued: 20170627/0123Z
Current Aviation Color Code: ORANGE
Previous Aviation Color Code: orange
Source: KVERT
Notice Number: 2017-150
Volcano Location: N 56 deg 38 min E 161 deg 18 min
Area: Kamchatka, Russia
Summit Elevation: 10768.24 ft (3283 m), the dome elevation ~8200 ft (2500 m)

 

 


Strong fumarole activity and an incandescence of hot avalanches on the lava dome of Molodoy Sheveluch volcano on 25 November, 2015.

Volcanic Activity Summary:
Video data show an ash explosion about 7 km a.s.l. moving to the east from the volcano.
Explosive-extrusive eruption of the volcano continues. Ash explosions up to 32,800-49,200 ft (10-15 km) a.s.l. could occur at any time. Ongoing activity could affect international and low-flying aircraft.

Volcanic cloud height: 21320-22960 ft (6500-7000 m) AMSL
Time and method of ash plume/cloud height determination: 20170627/0120Z – Video data
Other volcanic cloud information: Distance of ash plume/cloud of the volcano: 3 mi (5 km)
Direction of drift of ash plume/cloud of the volcano: E / azimuth 90 deg
Time and method of ash plume/cloud determination: 20170627/0120Z – Video data

Source : Kvert.

Photo : Yu. Demyanchuk, IVS FEB RAS, KVERT

 

Reventador , Ecuador :

Special Report on volcano Reventador N. 2-2017

Observations from 1 May to 29 June and 7 June, 2017
Ground mission from 29 May to 1 June 2017.

From 29 May to 01 June, the technical staff of the Geophysical Institute visited the El Reventador volcano to carry out monitoring tasks in the Azuela sector (UTM: 208539 m E, 9,991,842 m S) 4560 m northeast of the summit of the volcano (Fig.1).

 

 

Informe Especial Reventador N. 2 - 2017

Figure 1. route: Start point (green point), road (orange line) and location of the Azuela camp on the Reventador volcano (red point). Base: Wikiloc – Google Maps.

At the camp, mobile equipment was installed to monitor the volcano’s surface activity during the group’s working time. The instruments used were: a thermal camera, an infrasound sensor, a gas measuring equipment (MiniDoas) and a video camera (FIG. 2). The measurements were made during the time when the volcano was clear.

Informe Especial Reventador N. 2 - 2017

Figure 2. Camp located in the area of ​​Azuela. Photo: M Almeida (IG-EPN), 30/05/2017.

Climate:
The volcano has remained cloudy mostly sunny. Rainfall precluded the use of most equipment, which limited the collection of data. The average ambient temperature was 15.5 ° C and the wind direction changed from west to northeast.

Thermal:
10 thermal image sequences were performed, captured at a pre-established frequency of 1 second between each. These sequences made it possible to obtain an adequate recording of the surface activity of the volcano, where the various volcanic phenomena were observed: a lava flow deposited on the Northeast flank, several explosions and associated emissions of the North and South vents , collapse of the front of lava flowing down to the north, pyroclastic flows, blasts (audible gas intermittent emission in a short time) and ballistic projections.
Lava flow:
The new lava flow as seen on the top of the northeast flank of the volcano has a very low speed. It was almost imperceptible during field work and the only evidence of its continuous flow movement was the collapse of its active forehead, producing avalanches of rocks towards the base of the cone. A maximum apparent temperature (TMA) value of 304 ° C was obtained.
Breathing:
This phenomenon is very common on the volcano. It manifests itself by pulsatile exhalations of gas. Auditory perception manifests itself as the sound of a locomotive. During this study, the frequency capture images do not allow us to clearly see the gas emission pulses that characterize them. A maximum apparent temperature (TMA) of 65 ° C was obtained, which could also assume that the dominant gas of this phenomenon is H2O (g).
Explosions, pyroclastic fluxes and emission columns:
Several explosions were observed during the few moments when the volcano was clearly visible, but it was possible to hear them when visual conditions did not permit direct observations. The frequency of the explosions was about 15-30 minutes, as indicated in the seismic record (Figure 3).

Informe Especial Reventador N. 2 - 2017

Figure 3. Seismic record obtained for 30 and 31 May 2017, Reventador Nord station, closest to the camp. Base: IG-EPN.

It was evident that the volcano has two points of emission (North and South vents). The activity of these openings is characterized by gas emissions and the expulsion of ash and ballistics associated with small explosions. The columns of emission or explosion reached 1 to 2 km of altitude according to the energy of the explosion. The larger explosions also produced pyroclastic flows which exceptionally reached the base of the cone. The sound of explosions is easily heard several kilometers around the volcano ~ (5-8) km. The recorded sequence of explosions of the North vent (FIG 4) made it possible to measure a maximum apparent temperature of 241 ° C; The pyroclastic emission column (bombs and associated ash) gave a maximum apparent temperature (TMA) value of 129 ° C.

This time it was observed that small pyroclastic density secondary streams (CDP) associated with the collapse of the volcanic material accumulated at the top were generated. These CDPs have relatively low velocities and reach short distances, not exceeding the perimeter of the base of the cone. Thanks to a thermal sequence, it was possible to calculate a speed of 10.5 m / sec for this event. The duration from start to end of flow was 1 minute 16 seconds and reached a maximum distance of 800 meters. The maximum temperature range is 304 ° C, possibly associated with the large amount of gas released from the ash deposit at the end of the event. The second explosion occurred from the South Vent and did not generate CDP. The ballistic projections reached distances greater than the perimeter of the base of the cone ~ 1200 meters, similar to the explosions of the North vent. The maximum apparent temperature of thermal images for this phenomenon was 521 ° C. The emission column of pyroclastic materials (bombs and associated ash) gave a maximum apparent temperature value of 358 ° C (Fig. 4).

Informe Especial Reventador N. 2 - 2017

Figure 4. Temperature fluctuations in volcanic events related to volcanic activity during sequences recorded on the Reventador volcano from the Azuela camp. ( M Almeida – IGEPN.).

FIG. 4 shows the temperature variation curves for the duration of the previously established sequence for capturing an image every second.  It can be noted that the curves (fluctuations) are different for each of the recorded events. The breath shows an almost horizontal pattern without much variation and with a negative slope. The explosions show a series of peaks rising and falling (similar to the upper half of the seismic record), the first major peak (more energy release), and several consecutive low intensity pulses. In explosions that generate pyroclastic fluxes, a curve tendency is observed with a positive slope showing explosions of similar intensity and consecutive in short intervals of time. The latter also involve a greater accumulation of material at the top of the volcano. The pyroclastic flows show a curve with positive slopes where the observed peaks represent the breakage of the rocks and the degassing flows during its displacement, as well as the recharge of new materials emitted in the form of pulses subsequent to the main emissions. The lava flow is observed with a slope of « soft and sinuous » curve without showing a clear tendency to fluctuate temperatures.

Gas:
Meteorological conditions hindered the measurement of SO2 emissions from the volcano, but some measurements were available that yielded values ​​of about 150 tonnes per day (t / d).

Aerial survey of 7 June, 2017.
Staff at the Geophysical Institute conducted a surveillance survey of the Reventador volcano in a Cessna 206 – TURBO, led by Cap. Daniel Whitehead of the Empresa Alas de Socorro del Ecuador. The duration of the overflights was two hours on the volcano and followed the route indicated in Figure 5.

Informe Especial Reventador N. 2 - 2017

Figure 5. Path of the flight carried on 06.07.2017. (Base: Google Earth).

Climate:
Weather conditions were appropriate for imaging and thermal sequences, the volcano was quite clear, the presence of high clouds reduced the incidence of solar radiation on the volcano (Figure 6). Wind direction was variable from northwest to north prevailing (NW – N), mean air temperature was 5 ° C with 90% relative humidity.

Informe Especial Reventador N. 2 - 2017

Figure 6. Photo of the Reventador volcano. Photo: M Almeida (IG-EPN), 06/07/2017.

Visual Observations:
During the overflight, several recent deposits of pyroclastic flux on all sides of the volcano, the most obvious and longer (1.2 km) on the South and North sides, were verified. The presence of large volcanic bombs is known throughout the cone with a maximum range of 1.3 km. These ballistics did not damage the instruments installed in the areas closest to the crater. The presence of lava flow on the north-northeast flank is approximately 200 meters long and apparently unrelated to the North and South vents of the volcano, which gives the idea that it has been confirmed there may be a new vent from which this pour out. Several explosions were observed from the two orifices in the crater (Fig. 7).

Informe Especial Reventador N. 2 - 2017

Figure 7. Photo of the Reventador volcano, note the two vents located in the crater. Photo: P Ramon (IG-EPN), 07/06/2017.

During this mission, it was not possible to observe the generation of pyroclastic flows. However, recorded by the earthly mission, it was possible to confirm a parallel event, produced by the collapse of the accumulated matter during the previous explosions, coinciding with a greater explosion, the energy of which contributed to the destabilization of the materials. The proof of this hypothesis is a « recent » landslide of about 50 meters opening towards the north (Figure 8).

Informe Especial Reventador N. 2 - 2017

Figure 8. Photo of the Reventador volcano, note the slide open on the north side. Photo: M Almeida (IG-EPN), 06/07/2017.

Thermal:
Imaging and thermal sequences have allowed the identification of intense volcanic activity generating volcanic products from three emission centers: two associated with explosions, ballistic emissions and pyroclastic fluxes and that associated with a low lava flow (Figure 9).

Informe Especial Reventador N. 2 - 2017

Figure 9. Illustration of the three emission vents of the Reventador volcano. Illustration: M Almeida (IG-EPN), 07/06/2017.

In a general context, it can be seen that the two mouths show high temperatures, with the warmest on the North vent. The recordings of the temperatures of the lava flows are similar to those calculated during land shipment.

Gas:
During this aerial flight it was possible to obtain the first multi-gas measurement of the plume of the volcano. It was possible to measure the concentration of volcanic gases: CO2 = 620 ppmv, with an atmospheric CO2 = 437 ppmv, SO2 = 0.7 ppmv and H2S = 4 ppmv. The resulting ratio of CO2 / ST is quite high, between 35 and 40.

Source : IGEPN
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