Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week 31 August – 6 September 2022

Aira – Kyushu (Japan) : JMA reported low but continuing activity from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 29 August-5 September. Small eruptive events were recorded throughout the week, and crater incandescence was visible nightly. Sulfur dioxide emissions were 2,500 tons per day on 30 August, the same rate as the last measurement on 16 August.

Dukono – Halmahera : VMBG reported that daily ash plumes from Dukono rose as high as 800 m above the summit and drifted SW, W, and NW. The plume colors were various shades white, gray, and black and had variable densities from diffuse to dense.

Ebeko – Paramushir Island (Russia) : KVERT reported that moderate activity at Ebeko was ongoing. A thermal anomaly over the volcano was identified in satellite images on 25 and 31 August. According to volcanologists in Severo-Kurilsk (Paramushir Island, about 7 km E) explosions generated ash plumes during 25-26, 28, and 30-31 August, and 1 September, that rose up to 3.5 km (11,500 ft) a.s.l. and drifted N and E. Ashfall was reported in Severo-Kurilsk on 30 August.

Fuego – South-Central Guatemala : INSIVUMEH reported that 4-13 explosions per hour were recorded at Fuego during 30 August-6 September, generating ash plumes that rose as high as 1.1 km above the crater rim. The ash plumes drifted as far as 30 km N, NW, W, and SW, causing daily ashfall in areas downwind including Morelia (9 km SW), Panimaché I and II (8 km SW), Santa Sofía (12 km SW), El Porvenir (8 km ENE), Los Yucales (12 km SW), Sangre de Cristo (8 km WSW), El Porvenir (8 km ENE), San Pedro Yepocapa (8 km NW), and Finca Palo Verde. Daily shock waves rattled structures in communities within about 10 km around the volcano. Daily block avalanches descended the Ceniza (SSW), Seca (W), Trinidad (S), Taniluyá (SW), Honda, and Las Lajas (SE) drainages, often reaching vegetated areas. Explosions ejected incandescent material 100-300 m above the summit each day. Lahars resulting from substantial rainfall descended the Las Lajas and El Jute drainages on the ESE flank and the Ceniza drainage on the SSW flank during 29-30 August and on 2 September, carrying tree branches, trunks, and blocks as large as 2 m in diameter.

Great Sitkin – Andreanof Islands (USA) : AVO reported that slow lava effusion at Great Sitkin likely continued during 30 August-6 September with lava thickening over the vent and expanding outward; the lava flows did not advance. Minor steaming from the summit was observed during 30-31 August, and elevated surface temperatures were identified in satellite images during 2-5 September. Seismicity was very low. Weather clouds sometimes prevented satellite and webcam views.

Kadovar – Northeast of New Guinea : Based on satellite and wind model data, the Darwin VAAC reported that on 31 August an ash plume from Kadovar rose to an altitude of 1.2 km (4,000 ft) a.s.l. and drifted NW.

Karymsky – Eastern Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Karymsky was identified in satellite images during 25 August-1 September.

Kilauea – Hawaiian Islands (USA) : HVO reported that lava continued to effuse from a vent in the lower W wall of Kilauea’s Halema`uma`u Crater during 30 August-6 September, entering the lava lake and flowing onto the crater floor. Part of the lake’s surface was continuously active. The lake level mostly remained within the bounding levees, though breakouts were visible along the W and NW margins.

Klyuchevskoy – Central Kamchatka (Russia) : Strong winds re-suspended ash from the E flank of Klyuchevskoy and created plumes that were visible in satellite and webcam images drifting 180 km E on 5 September, local time. The plumes rose to altitudes of 3-4 km (9,800-13,100 ft) a.s.l.

Kuchinoerabujima – Ryukyu Islands (Japan) : The number of volcanic earthquakes with hypocenters near Kuchinoerabujima’s crater increased during 30-31 July. The number of earthquakes then decreased to low levels by 1 August and remained low. Sulfur dioxide emissions were also at low levels and on some days were below the detection limit.

Lewotolok – Lembata Island : PVMBG reported that the eruption at Lewotolok continued during 30 August-6 September. Daily white emissions rose as high as 500 m above the summit and drifted NW, W, and SW. During 1-2 September white, gray, and black plumes rose as high as 1.5 km above the summit.

Merapi – Central Java : BPPTKG reported that the eruption at Merapi continued during 26 August-1 September and seismicity remained at elevated levels. As many as 13 lava avalanches from the SW lava dome traveled down the Bebeng drainage on the SW flank, reaching a maximum distance of 2 km. The SW lava dome had continued to grow, and had an estimated volume of 1.62 million cubic meters based on 29 August aerial photographs.

Pavlof – Alaska Peninsula, Alaska : AVO reported that a minor eruption at a vent on Pavlof’s upper E flank was ongoing during 30 August-6 September. A small vent re-opened ESE of the main vent. Seismic tremor persisted. Weather clouds mostly prevented views of the volcano during the first part of the week, though incandescence from the vent was visible in webcam images at night on 1 September; elevated surface temperatures were identified in satellite images during 2-6 September. A diffuse gas plume visible in webcam images on 4 September possibly contained trace amounts of ash. Gas plumes visible the next day contained minor amounts of ash.

Santa Maria – Southwestern Guatemala : INSIVUMEH reported that the eruption at Santa María’s Santiaguito lava-dome complex continued during 30 August-6 September. Lava-dome effusion at Caliente cone fed lava flows that descended the San Isidro and El Tambor drainages on the W and SW flanks; the flows were as long as 4.2 km by 30 August. Block avalanches from the dome, and from both the ends and sides of the flows, descended the SW and W flanks. The avalanches sometimes generated ash plumes that rose as high as 500 m above the complex. Incandescence from the dome and the lava flows was sometimes visible at night or during early mornings. Explosions during 31 August-1 September occasionally ejected incandescent material onto the flanks in all directions.

Semeru – Eastern Java : PVMBG reported that the eruption at Semeru continued during 30 August-6 September. Eruptive events at 0756 on 2 September, 0518 and 0956 on 5 September, and 0521 on 6 September produced ash plumes that rose 500-700 m above the summit and drifted mainly N and SW.

Sheveluch – Central Kamchatka (Russia) : KVERT reported that the ongoing eruption at Sheveluch was characterized by explosions, hot avalanches, and lava-dome extrusion during 25 August-1 September. A daily thermal anomaly was identified in satellite images. Plumes of re-suspended ash drifted 150 km E on 25 August. Hot avalanches generated an ash plume on 1 September that drifted 70 km E.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that the eruption at Suwanosejima’s Ontake Crater continued during 31 August-5 September. There were four explosions that likely produced eruption plumes, though weather clouds prevented visual confirmation. Large blocks were ejected 700 m from the vent. Crater incandescence was observed nightly, and volcanic tremor was occasionally recorded.

Whakaari/White Island – North Island (New Zealand) : On 7 September GeoNet reported that access to continuous data streams from the last operating earthquake and pressure sensor on Whakaari/White Island had recently been lost, hindering scientists’ ability to distinguish between various levels of unrest. Observations and gas-monitoring flights will be conducted more frequently until the island can visited to service the equipment and power supplies. Images from island webcams continued to be intermittently available. The report noted that low levels of activity on the island were observed during the last overflight on 31 August. Tall steam-and-gas plumes are sometimes observed from the mainland coast.

from WordPress https://ift.tt/TvfKlOV