October 08 , 2020.
Italy / Sicily , Etna :
COMMUNICATION ON ETNA’S ACTIVITY [UPDATE]
The National Institute of Geophysics and Volcanology, Osservatorio Etneo, reports that from the early hours of the morning, a moderate and variable intensification of Strombolian activity of the New Southeast Crater (NSEC) is observed. The explosive activity produces an eruptive cloud which rises about 4.5 km and disperses to the east.
The trend of the average amplitude of the tremor continues to present oscillations which globally define a substantially stationary value which is maintained mainly in the range of the average values. The location of the source of the tremor is located near the area of the New Southeast Crater, at an altitude of about 2900-3000 meters above mean sea level. The infrasound activity is characterized by low frequency of occurrence of events. The signals from the soil deformation monitoring stations show only a modest variation at the Pizzi Deneri and Punta Lucia tilt stations, linked to the seismic activity of the summit yesterday afternoon.
Further updates will be communicated shortly.
Bocca Nuova, 3270m. Summit Craters Etna 08/12/2020
Weekly bulletin, from September 28, 2020 to October 04, 2020
(issue date 06 October 2020)
SUMMARY OF THE STATE OF ACTIVITY
In the light of the surveillance data, it is highlighted:
1) VOLCANOLOGICAL OBSERVATIONS: Variable Strombolian activity with ash emission at the New Southeast Crater; Strombolian activity within the deep crater at the Northeast Crater; isolated and light ash emissions at the Voragine crater; degassing activity at the Bocca Nuova.
2) SEISMOLOGY: Seismic activity of modest fracturing. Amplitude of the tremor between the average and high values.
3) INFRASOUND: low infrasound activity.
4) DEFORMATIONS: Etna’s soil deformation monitoring networks have not shown significant variations over the past week, unless the Monte Fontane GNSS station is shifted by one centimeter towards the ‘East.
5) GEOCHEMISTRY: The flow of SO2 occurs at an average level.
HCl flow occurs at an average level.
Soil CO2 flux values are at medium-low degassing levels.
The partial pressure of dissolved CO2 does not show significant changes.
No update is available for the C / S report (last measurement of 07/17/2020).
The isotope ratio of helium is on average values (last update of 09/22/2020).
6) SATELLITE OBSERVATIONS: The thermal activity in the summit area is at a medium-low level.
Eruptive activity at the summit craters of Etna, October 5, 2019
The summit craters of Etna seen from a helicopter in the afternoon of October 5, 2019. On the left, we can observe the continuous emission of gray ash from the Northeast crater. At 00:30 an explosion begins with the emission of dark gray ash from the Voragine. The great Bocca Nuova depression with its two internal wells (BN-1 and BN-2) is to the right, while the Southeast Crater / New Southeast Crater complex is visible behind the other craters. Video recorded by Boris Behncke (INGV-Osservatorio Etneo) during a flight over Butterfly Helicopters
VOLCANOLOGICAL OBSERVATIONS
The monitoring of the volcanic activity of Etna, during the week in question, was carried out by analyzing the images of the network of surveillance cameras of the INGV, Osservatorio Etneo (INGV-OE), and through various observations made by INGV-OE staff. Due to weather conditions, the observation of volcanic activity was partially limited.
The New Southeast Crater was also characterized by variable and moderate explosive activity which, in phases of greater intensity, formed a cloud of often diluted volcanic ash outside the summit area. On the morning of October 1, ash emissions increased in intensity, forming, as seen by INGV-OE surveillance cameras, a volcanic cloud about 4.5 km above sea level. A slight increase in explosive activity also occurred on October 3-4. In both cases, the volcanic ash was mainly dispersed towards the Valle Del Bove forming, outside the summit area, a diluted volcanic cloud. During the whole week, no report of fallout of volcanic ash on the inhabited centers of Etna was received.
As also observed by INGV-OE personnel present in the summit area, deep intracrater Strombolian activity continues at the Northeast Crater with product launches inside the crater rim. The Voragine crater was mainly characterized by degassing activity and by light and isolated emissions of volcanic ash. Rather, the Bocca Nuova crater was characterized by degassing activities.
The immense Crater of Bocca Nuova (1968), Summit of Etna 3250 m. October 1, 2020.
During the week, the mapping laboratory carried out remote surveys using drones of the area of the summit of Etna in order to characterize its morpho-structural arrangement, the analysis of the data made it possible to develop a 3D model of the crater areas. In particular for the Bocca Nuova, it appears that the Central vent is elliptical in shape with a minor and major axis of 60 and 100 m respectively, moreover, compared to the morphological update of July 24, no substantial change n ‘has been observed. The North-West vent is also elliptical in shape with an axis less than 70 m and greater than 80 m.
Volcanic tremor:
During the week in question, the average amplitude of the volcanic tremor showed significant and transient fluctuations mainly inside the average level. In short periods, some values of the mean amplitude reached the high level. The location of the source of the tremor is located near the New Southeast Crater area at a depth of approximately 2900-3000 m above sea level
COMMUNICATION ON ETNA’S ACTIVITY [UPDATE]
The National Institute of Geophysics and Volcanology, Osservatorio Etneo, announces that the increase in explosive activity reported in the previous press release (Press release Etna ‘Update n.83 at 07:16 UTC) is no longer observable but strombolian activity of varying intensity remains at the New Southeast Crater (NSEC). This activity produces discontinuous and weak ash emissions which are dispersed in the summit area. We inform you that since the previous update, the temporal trend of the amplitude of the volcanic tremor has not shown significant variations and continues to remain within the range of average values. Infrasound activity, like volcanic tremor, does not show variations and continues to remain at low values. The source of tremors and infrasound events is mainly located near the New Southeast Crater (NSEC) area. It should be noted that the seismic network stations at 07:01 UTC recorded a seismic event of Ml = 2.9, located 1.4 km east of the central craters (CT). Furthermore, with regard to what is reported in press release no. 83, it should be noted that almost all the stations of the inclinometric network detected a modest variation during the seismic event that occurred in the summit area at 07:01 UTC; at the stations in the summit area, the variation is permanent.
Further updates will be communicated shortly.
Source : INGV.
Photos : Gio Giusa.
Vidéo : INGV / Boris Behncke / Butterfly Helicopters.
Italy , Stromboli :
Weekly bulletin, from September 28, 2020 to October 04, 2020
(issue date 06 October 2020)
SUMMARY OF THE STATE OF ACTIVITY
In the light of the surveillance data, it is highlighted:
1) VOLCANOLOGICAL OBSERVATIONS: Normal explosive volcanic activity of Strombolian type on medium-low and medium levels (9-14 events / h) with the sole exception of September 28 with 23 events / h (high values) and with medium intensity- low in the area of the North craters and medium-high in the Center-South area.
2) SEISMOLOGY: The seismological parameters do not show significant variations.
4) DEFORMATIONS: No significant variation is observed.
5) GEOCHEMISTRY: Medium-low SO2 flux.
There are no updates on the soil CO2 flux data.
C / S Ratio – Data not available. The latest values are at medium-low levels (5.45, measurements from 13/09/2020).
Isotope ratio of He – The latest measurements (09/22/2020) are average values.
6) SATELLITE OBSERVATIONS: The thermal activity in the summit area is at a medium-low level.
VOLCANOLOGICAL OBSERVATIONS:
In the area of the North crater, the N1 crater, with two emission points, produced low to medium intensity explosions (less than 150 m high) emitting coarse materials (lapilli and bombs) sometimes mixed with fine materials (ash). Vent N2 mainly exhibited low intensity explosive activity (less than 80 m in height) emitting coarse materials. The average frequency of explosions varied from 6 to 13 events / h with the exception of September 28 with 22 events / h.
In the Center-South zone, the explosions emitting mainly fine materials sometimes mixed with coarse materials with a medium-high intensity (the products emitted often exceeded 250 m in height). The frequency of the explosions varied from less than 1 to 4 events / h.
Source : INGV.
Photo : webcam / Wolfgang Künker
Kamchatka , Sheveluch :
VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA).
Issued: October 08 ,2020
Volcano: Sheveluch (CAVW #300270)
Current aviation colour code: ORANGE
Previous aviation colour code: orange
Source: KVERT
Notice Number: 2020-184
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)
Volcanic Activity Summary:
A growth of the lava dome continues, a strong fumarolic activity, and an incandescence of the dome blocks accompanies this process. Satellite data by KVERT showed a resuspended ash plume extended to the southeast of the volcano.
The 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.
A new lava block is being extruded out in the eastern part of the lava dome of Sheveluch volcano.
A unique phenomenon was discovered on September 28, 2020 on the Sheveluch volcano. A block of lava of the most acsid composition in the entire history of development (since 1980) of the volcano’s lava dome is being extruded out. The likely composition of the lava is dacitic. The dome is named Dolphin.
Volcanic cloud height:
6560-8200 ft (2000-2500 m) AMSL Time and method of ash plume/cloud height determination: 20201007/2230Z – Video data
Other volcanic cloud information:
Distance of ash plume/cloud of the volcano: 93 mi (150 km)
Direction of drift of ash plume/cloud of the volcano: ESE / azimuth 113 deg
Time and method of ash plume/cloud determination: 20201007/2200Z – Himawari-8
Source : Kvert.
Photo : Yu. Demyanchuk. IVS FEB RAS.
Nicaragua , Telica :
The expert Agustin Moreira informed 100% Noticias that the Telica volcano records a degassing process due to the last rains that occur in the West “we had enough precipitation in the region near Telica, these rainy conditions are eroding the crater walls and cause landslides and fall to the bottom of the crater. By nature, pressure expels this type of material, ”he explained.
On social networks, images of gas columns reaching up to 300 meters were circulating « If it was an eruptive phase, we would maintain a permanent record of volcanic material, but what we actually have is this are internal activities inside the crater due to landslides and degassing « , explained the meteorological expert.
The expert in natural phenomena explained that the degassing process is due to precipitation. “It rains and it falls on the hot fumarole, generating steam and these white columns. A considerable degassing to produce this effect, we do not have a strong eruption but sporadic explosions in the Telica volcano ”, he explained.
Source et photo : 100% Noticias.
