Volcano World

Sezione di Catania - Osservatorio Etneo (INGV) reported that an eruption at Etna continued during 8-14 July. The eruption was characterized by a gradual increase of Strombolian activity within the Voragine Crater on 10 July, and ash emissions on 11 July. The Toulouse VAAC issued advisories for an ash emission that rose about 1 km above the summit (12,000 ft a.s.l.) and drifted S. After a few days of decreased activity, explosions gradually increased in the NE Crater (NEC) and Voragine on 14 July, generating ash emissions that quickly dispersed above the craters; light ash emissions continued afterwards from both craters. The amplitude of volcanic tremor rapidly fluctuated between medium and high levels. Signal locations shifted from an area just E of the Voragine crater to the SE Crater area on 12 July, and then shifted again to the NEC area on 14 July.

Sources: Sezione di Catania - Osservatorio Etneo (INGV),Toulouse Volcanic Ash Advisory Centre (VAAC)

Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) raised the Alert Level at Ijen from 1 to 2 (on a scale of 1-4) at 2200 on 12 July (local time). The recommended exclusion zone radius was expanded from 500 to 1,500 m away from the crater due to a notable increase in seismic energy, as well as an increase in continuous tremor amplitudes. Realtime seismic amplitude measurement (RSAM) analysis has shown that seismic energy has slowly increased since 1 January 2023. However, a significant increase in energy was observed from 1700 through 2100 on 12 July, along with an increase in continuous tremor amplitudes starting at 2110. From 1 June through 12 July there was a decreasing trend in the number of both shallow volcanic earthquakes (Type B/vulkanik dangkal) and deep volcanic earthquakes (Type A/vulkanik dalam), while the number of other types of earthquakes fluctuated normally. On 30 June the surface temperature of the crater lake water was 34C, which falls within the normal range. Weak to moderate fumarolic activity was observed, characterized by dense white emissions. The color of the water appeared turquoise green, as usual, with no visible gas bubbles on the surface of the lake. The smell of sulfur gas was moderately strong, and sulfur spherules were observed at the edge of the crater lake. White emissions were observed rising 50-100 m above the summit on 10, 12-13, and 16 July, and 50-200 m on 14 July. Emission observations were not reported on 11 or 15 July. Seismicity during 10-16 July included daily gas emission events and continuous tremor, volcanic earthquakes during 13-16 July, and a volcano-tectonic (VT) earthquake on 16 July. PVMBG reminded the public to stay vigilant of the potential for poisonous gases emanating from the crater lake.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)

The Kamchatka Volcanic Eruption Response Team (KVERT) reported that moderate explosive activity continued at Karymsky during 4-11 July. Satellite data analyzed by KVERT showed that explosions on 5-7 and 10 July generated ash plumes that rose about 2.5 km above the summit (to 4 km a.s.l.) and drifted as far as 80 km NE and E. Additionally, a thermal anomaly was observed over the volcano during 5-7 and 10 July; weather clouds prevented observations in satellite images on the other days. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are reported in UTC; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

Pilots reported small low-level eruptions at Matthew Island, about 440 km E of the southern end of New Caledonia, at 0409 and 2150 on 16 July (UTC). However, ash was not visible in satellite data for either event.

Source: Wellington Volcanic Ash Advisory Center (VAAC)

Istituto Nazionale di Geofisica e Vulcanologia (INGV) reported that eruptive activity continued at Stromboli during 8-14 July. Lava flows that started on 4 July from two eruptive vents, located at approximately 485 and 510 m a.s.l. along the Sciara del Fuoco, had ended by 12 July. Starting at around 1208 on 11 July (UTC), a series of explosive events over about 8 minutes generated pyroclastic flows that rapidly descended to the shoreline and continued into and across the surface of the sea. The first explosion took place in Area C-S, releasing moderately hot ash. Another explosion from Area N then created an eruption column that reached approximately 5 km above sea level and dispersed towards the WSW. Almost simultaneously, a pyroclastic flow descended along the Sciara del Fuoco and reached the coastline in about 23 seconds, traveling at a speed of approximately 58 m/s. The sequence concluded with a series of secondary pyroclastic flows between 1210 and 1215. Both effusive and explosive activities ceased within hours after these events, except for a single final explosion at 0828 on 12 July that triggered a small landslide from the exterior of the N crater. Thermal anomalies with high-level thermal flux values (greater than 100 MW) were identified in satellite images during both the effusive and explosive activity. The thermal flux values slightly increased at 1157 on 11 July, about 11 minutes before the explosion sequence, and then dropped at 1352 (SEVIRI sensor onboard the Meteosat Second Generation satellite). Dipartimento della Protezione Civile maintained the Alert Level at Red (the highest level on a four-level scale).

Sources: Dipartimento della Protezione Civile,Sezione di Catania - Osservatorio Etneo (INGV)

GeoNet reported moderate emissions of steam, gas, and minor ash at Whakaari/White Island during 10-12 July. The continuous, moderate emissions rose from an enlarged vent on the crater floor where the crater lake has almost disappeared. The intermittent observations of ash were thought to originate from the walls of the vent eroded by vigorous degassing, and do not represent new eruptive activity; no ash was detected in the plume outside of the crater. The Volcanic Alert Level remained at 2 (on a scale of 0-5) and the Aviation Color Code remained at Yellow (the second level on a four-color scale).

Source: GeoNet

Japan Meteorological Agency (JMA) reported ongoing eruptive activity at Minamidake Crater (Aira Caldera?s Sakurajima volcano) during 8-15 July. Nighttime crater incandescence was visible. An explosion at 2123 on 10 July produced an ash plume that rose 2.3 km above the crater rim and drifted E, and also ejected large blocks up to 1.1 km from the vent. An explosion at 1819 on 14 July produced an ash plume that rose 4.5 km above the crater rim and drifted NE, with large blocks ejected up to 1.4 km from the vent. The Alert Level remained at 3 (on a 5-level scale), and the public was warned to stay 1 km away from both craters.

Source: Japan Meteorological Agency (JMA)

The Kamchatka Volcanic Eruption Response Team (KVERT) reported that moderate explosive activity was ongoing at Ebeko during 4-11 July. Webcam images showed explosions on 5 and 7 July that generated ash plumes that rose about 1.9 km above the summit (to 3 km a.s.l.); satellite data confirmed the ash plume drifted as far as 30 km NE. A thermal anomaly was observed over the volcano during 5-7 July in satellite images analyzed by KVERT; weather clouds prevented views on the other days. The Aviation Color Code remained at Orange (the third level on a four-color scale). Dates are reported in UTC; specific events are in local time where noted.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)

Instituto Nacional de Sismologa, Vulcanologia, Meteorologia e Hidrologa (INSIVUMEH) reported that eruptive activity continued at Fuego during 10-16 July. Daily explosions were recorded by the seismic network, ranging from 2-11 explosions per hour. The explosions generated gas-and-ash plumes that rose as high as 1.1 km above the crater rim and drifted as far as 30 km in multiple directions. The explosions produced block avalanches that descended various drainages including the Ceniza (SSW), Seca (W), Taniluy (SW), Trinidad (SSW), and Las Lajas (SE), and Honda (E), and often reached vegetated areas. Weak rumbling sounds and shock waves were reported on most days. Ashfall was reported on 10, 12, 14, and 16 July in areas downwind including Panimach I and II (8 km SW) Finca Paloverde (10 km SW), El Porvenir (10 km S), Santa Sofia (12 km SW), Sangre de Cristo (10 km SW), Morelia (10 km SW), Los Yucales (12 km SW), Yepocpa (8 km NW), and other nearby communities. Ashfall was forecast for areas downwind on some of the other days. The explosions also ejected incandescent material up to 100 m above the summit during 10-11 and 13-16 July. On 12 July lahars descended the Las Lajas, Seca, and Mineral drainages, carrying tree branches, trunks, and blocks as large as 1.5 m in diameter.

Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)

Alaska Volcano Observatory (AVO) reported that slow lava effusion in Great Sitkin?s summit crater likely continued during 10-16 July. Seismicity was low with few daily small earthquakes recorded by the seismic network. Daily clear webcam views showed minor steaming from the active lava flow, and on 15 July elevated surface temperatures were detected by satellite. The Volcano Alert Level remained at Watch (the third level on a four-level scale) and the Aviation Color Code remained at Orange (the third color on a four-color scale).

Source: US Geological Survey Alaska Volcano Observatory (AVO)