September 23 , 2026.
Italy / Sicily , Etna :
WEEKLY BULLETIN, September 14, 2026 – September 20, 2026 (Date of issue: September 22, 2026)
SUMMARY OF ACTIVITY STATUS
Based on monitoring data, the following is noted:
1) VOLCANOLOGICAL OBSERVATIONS: Variable degassing activity at the summit craters; ash emissions from the Northeast Crater alternating with the Bocca Nuova crater; Strombolian activity at the Bocca Nuova crater.
2) SEISMOLOGY: Low seismic activity associated with fracturing. Average volcanic tremor amplitude moderately variable, fluctuating between low and medium values.
3) INFRASOUND: Generally medium to low infrasonic activity, localized primarily at the Bocca Nuova crater.
4) GROUND DEFORMATION: Signals from ground deformation monitoring networks showed no significant variations.
5) GEOCHEMISTRY: SO2 flux at a medium level.
Soil CO2 flux (Etnagas): medium to high values.
Partial pressure of dissolved CO2 in groundwater (EtnaAcque network): no update.
Helium isotopic ratio at peripheral sites: no update; the last data indicated high values (August 26, 2026).
6) SATELLITE OBSERVATIONS: Thermal activity observed by satellite in the summit area remained generally low.
7) OTHER OBSERVATIONS: Data from the RADONETNA network during September 2026 revealed various anomalies—both positive and negative—across all sites. Anomalous variations appeared first at sites on the southern flank, followed by those on the eastern and northern flanks.
VOLCANOLOGICAL OBSERVATIONS
Throughout the week, monitoring of Etna’s volcanic activity was conducted via the analysis of images from INGV–Etna Observatory (INGV-OE) surveillance cameras. On a daily basis, visual and thermal observations during the afternoon were significantly hampered by cloud cover.
Activity at the summit craters was characterized by near-continuous ash emissions from the North-East Crater (NEC) on September 14 and 15, as well as again from the morning through the afternoon of the 16th; meanwhile, the BN1 vent, located in the western section of the Bocca Nuova (BN) crater, exhibited modest Strombolian activity that persisted throughout the night of September 15–16. From the afternoon of the 16th until dawn on September 18, this same vent produced continuous ash emissions. Subsequently, ash emissions ceased almost entirely; for the remainder of the week, only weak, sporadic puffs of ash were observed from both the NEC and the BN.
Regarding the other summit craters—Voragine and the South-East Crater—customary fumarolic activity continued along numerous fractures lining the crater rims.
Source : INGV.
Photo : Gio Giusa ( capture d’écran).
Italy , Stromboli :
WEEKLY BULLETIN, September 14, 2026 – September 20, 2026 (issue date: September 22, 2026)
ACTIVITY SUMMARY
Based on monitoring data, the following is noted:
1) VOLCANOLOGICAL OBSERVATIONS: Ordinary Strombolian eruptive activity in both crater zones, accompanied by spattering in the North crater zone. Total explosive activity frequency (including North and Central-South crater zones) at a medium-high level; explosion intensity was low in both the North and Central-South crater zones.
2) SEISMOLOGY: Monitored seismic parameters show no significant variations.
3) GROUND DEFORMATION: Signals from ground deformation monitoring networks showed no significant variations.
4) GEOCHEMISTRY: SO2 flux at a medium-high level.
Soil CO2 flux (Pizzo zone – STR02): no update.
C/S ratio in the plume: no update.
Helium isotope ratio (R/Ra): no update.
Soil CO2 flux in the San Bartolo zone: high values.
Soil CO2 flux in the Scari zone: no update.
5) SATELLITE OBSERVATIONS: Satellite-observed thermal activity in the summit area ranged from low to medium.
VOLCANOLOGICAL OBSERVATIONS
Observations of explosive activity captured by surveillance cameras
During the observation week, Stromboli’s eruptive activity was characterized through the analysis of images recorded by INGV-OE surveillance cameras located at an elevation of 190 m above sea level and at Punta dei Corvi (SCT-SCV and SPCT, respectively). Explosions in the North crater area (Zone N) primarily produced coarse material (bombs and lapilli); in the Central-South crater area (Zone CS), explosions produced material that was predominantly fine, mixed with coarse material. The average explosion frequency in Zone N was moderately high, while the intensity remained generally low.
In Zone CS, the average explosion frequency was moderate, and the intensity of explosive activity was generally low. The total daily average hourly frequency of explosions (Zone N + Zone CS) was moderately high.
Source : INGV.
Photo : Stromboli stati d’animo / Sebastiano Cannavo
Hawaii , Kilauea :
HAWAIIAN VOLCANO OBSERVATORY DAILY UPDATE , U.S. Geological Survey
Tuesday, September 22, 2026, 8:51 AM HST (Tuesday, September 22, 2026, 18:51 UTC)
19°25’16 » N 155°17’13 » W,
Summit Elevation 4091 ft (1247 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE
Summary:
The north, south, and west vents continue to glow with minor intermittent spatter from the north and south vents. Minor summit inflation continued overnight. There is no anomalous activity outside of the summit.
Overview:
Glow and flames continued from the north-south-west vent complex throughout the night, with minor intermittent spatter from the north and south vents. Slow inflation continues at the summit, gaining approximately 0.2 microradians over the past day. Over the past 24 hours strong, continuous tremor remains the dominant seismic signal across the summit. No anomalous seismic activity or deformation has occurred outside of the summit region.
The system is within about a day, at the current slow rate of inflation, of reaching the maximum inflation of 16 microradians of tilt recovered since episode 54 fountaining ended. When this peak pressurization is reached, it is possible that activity will resume at the north-south-west vent complex, or reactivate the vent 1-6 system, or intrude another weak area in the summit region. None of these events are likely to produce a strong seismic precursor, so the alert levels remain at ORANGE/WATCH as the volcano continues to « exhibit heightened unrest with an increased potential for eruption ».
Summit Observations:
The north, south, and west vents continued to glow and emit flames. Intermittent spatter was also observed from the north and south vents last night. Flames from the north vent could be seen burning almost continuously in the early morning darkness. A very small, spatter-fed flow traveled about 15-35 feet (5-10 meters) from the north vent cone between 7:23-7:24 p.m. HST last night. No other significant spatter was deposited outside of the vents. No other areas of incandescence were observed across the summit region last night.
Strong continuous tremor is the dominant seismic signal across the summit. There were six small earthquakes located across the summit region in the past day, but they did not form clusters in time or location.
Summit inflation continues this morning, recording an increase of about 0.2 microradians over the past day. The current total inflation since the end of episode 54 is currently about 15.8 microradians, slightly less than the maximum of 16 microradians reached on September 16 and more than two microradians greater than was lost during episode 54 fountaining.
During inter-episode pauses, the sulfur dioxide (SO2) emission rate from the summit typically varies between 1,000 and 5,000 tonnes per day.
Rift Zone Observations:
Rates of seismicity and ground deformation remain low in the East Rift Zone and Southwest Rift Zone. SO2 emissions from the East Rift Zone remain below the detection limit. No significant ground deformation was recorded in either rift zone.
Source : HVO.
Photo : Alyssa Lee ( capture d’écran).
Colombia , Chiles / Cerro Negro :
San Juan de Pasto, September 22, 2026, 5:10 PM.
Based on monitoring of activity at the Chiles-Cerro Negro volcanic complex (CVCCN), the Colombian Geological Service (SGC)—an agency attached to the Ministry of Mines and Energy—
reports the following:
For the period from September 15 to 21, 2026, the main variations in monitored parameters compared to the previous week were as follows:
● Amidst the fluctuating behavior of this volcanic complex, seismic activity showed a slight decrease in both frequency and energy release.
The most frequent events during the week were those linked to fluid dynamics from a persistent source, followed by events associated with rock-fracturing processes.
● Overall, seismicity associated with fracturing processes was concentrated in the western and southern sectors of the Chiles volcanic edifice, at distances of less than 4.2 km;
at depths of up to 8.0 km below the summit (4,700 m above sea level) and with a maximum magnitude of 1.7. A few events were more widely dispersed, occurring up to 11.5 km east of the Chiles volcano, at maximum depths of 8 km below the summit and with a maximum magnitude of 1.6. No earthquakes were felt by residents in the area surrounding the volcano.
● Analysis of data from satellite sensors and ground-based stations continued to show variations associated with deformation processes
in the volcanic zone.
Based on the assessment and correlation of monitored parameters, the SGC recommends closely tracking their evolution via weekly bulletins and other information released through our official channels, as well as adhering to instructions from local and departmental authorities and the National Unit for Disaster Risk Management (UNGRD).
Volcanic activity remains at the yellow alert level: an active volcano showing behavioral changes relative to the baseline of monitored parameters, along with other manifestations.
Source et photo : SGC.
Indonesia , Ili Lewotolok :
An eruption of Mount Ili Lewotolok occurred on Monday, September 21, 2026, at 5:31 PM WITA, with an observed ash column rising approximately 800 m above the summit (or approximately 2,223 m above sea level). This dense, gray ash column drifted toward the west and northwest. The eruption was recorded by the seismograph with a maximum amplitude of 40 mm and a duration of 27 seconds.
Seismic observations
269 eruptive earthquakes: amplitudes of 11.7–40 mm, durations of 30–98 seconds.
228 emission earthquakes: amplitudes of 5.8–40 mm, durations of 20–64 seconds.
2 harmonic tremors: amplitudes of 3.9–7.8 mm, durations of 92–153 seconds.
28 non-harmonic tremor episodes: amplitudes of 3.9–40 mm, durations of 74–280 seconds.
4 hybrid/multiphase earthquakes: amplitudes of 7.8–9.7 mm, durations of 15–23 seconds.
1 shallow volcanic earthquake: amplitude of 3.9 mm, duration of 13 seconds.
2 deep volcanic earthquakes: amplitudes of 3.9–15.6 mm, durations of 11–17 seconds.
1 distant tectonic earthquake: amplitude of 40 mm, duration of 116 seconds.
Recommendations
1. Communities living near Mount Ili Lewotolok, as well as visitors, climbers, and tourists, must not enter or conduct activities within a 2 km radius—extending to 3 km in the South and Southeast sectors—of the Mount Ili Lewotolok activity center.
2. Remain vigilant regarding potential hazards associated with lava avalanches/rockfalls and pyroclastic flows in the South and Southeast, West, and Northeast sectors of Mount Ili Lewotolok.
Source et photo : PVMBG.
