Saturday, 20 March 2021

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the Week 10 March 2021 – 16 March 2021

Aira – Kyushu (Japan) : JMA reported that during 8-15 March incandescence from Minamidake Crater (at Aira Caldera’s Sakurajima volcano) was visible nightly. Seven explosions and 10 non-explosive events generated eruption plumes that rose 2.4-2.7 km above the crater rim and ejected bombs 0.8-1.7 km away from the crater. The sulfur dioxide emission rate was 2,300 tons per day on 10 March. The Alert Level remained at 3 (on a 5-level scale).

Dukono – Halmahera (Indonesia) : Based on satellite and wind model data, the Darwin VAAC reported that during 10-16 March ash plumes from Dukono rose to 2.1-2.4 km (7,000-8,000 ft) a.s.l. and drifted in multiple directions. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 2-km exclusion zone.

Ebeko – Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 5, 7-9, and 11-12 March that sent ash plumes to 2.3 km (7,500 ft) a.s.l. and drifted NE and E. Ashfall was reported in Severo-Kurilsk during 7-8 March. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Kadovar – Papua New Guinea : Based on satellite and wind model data, the Darwin VAAC reported that on 11 March ash plumes from Kadovar rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted W.

Kilauea – Hawaiian Islands (USA) : HVO reported that vents on the inner NW wall of Kilauea’s Halema`uma`u Crater continued to supply the lava lake during 10-16 March. Lava flowed from both the main vent and a newer vent several meters NE into the lake through submerged inlets. Another lava flow emerged from about halfway up the cone structure starting at 0220 on 16 March. The depth of the western part of the lake rose from 221 m to 222 m and lava continued to circulate in that part. The E half of the lake remained solidified and lower that the W half, with the crusted E half expanding towards the W. The sulfur dioxide emission rate was 900 tons/day on 14 March. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Klyuchevskoy – Central Kamchatka (Russia) : KVERT reported that the Strombolian eruption from vents on Klyuchevskoy’s lower NW flank continued during 5-12 March. A large, bright thermal anomaly over the vents was identified daily in satellite images. A plume of re-suspended ash drifted 375 km E on 5 March. IVS FEB RAS posted that the lava traveled downslope, melting ice and snow on the Erman glacier; the meltwater formed mud flows along the along the Krutenkaya River. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Lewotolok – Lembata Island (Indonesia) : PVMBG reported that the Strombolian eruption at Lewotolok continued during 10-16 March. Daily gray-and-white ash plumes rose as high as 1.5 km above the summit and drifted mainly E and SE. The eruptive events were accompanied by rumbling and banging sounds. Visual observations were hindered by weather on 10 March; each day during 11-16 March incandescent material was ejected as high as 500 m above the crater. Almost daily incandescent material was ejected 500-1,300 m E and SE from the crater. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 4 km away from the summer crater.

Merapi – Central Java (Indonesia) : BPPTKG reported that the 2021 lava dome just below Merapi’s SW rim and the lava dome in the summit crater both continued to grow during 5-11 March. The 2021 lava-dome volume was an estimated 785,600 cubic meters on 11 March, with a growth rate of about 13,500 cubic meters per day, and continued to shed material down the flank. A total of 12 pyroclastic flows traveled a maximum of 1.9 km down the SW flank. Incandescent avalanches, recorded 226 times, traveled as far as 1.3 km down the SW flank. The height of the summit lava dome was relatively steady at 45 m. The Alert Level remained at 3 (on a scale of 1-4), and the public were warned to stay 5 km away from the summit.

Popocatepetl – Mexico : During an overflight of Popocatépetl on 5 March scientists from Instituto de Geofísica de la Universidad Nacional Autónoma de México (UNAM) and CENAPRED observed that the inner crater was 360-390 m in diameter and 150-182 m deep. Tephra deposits on the crater floor were visible and there was no sign of a lava dome. Each day during 10-15 March there were 35-104 steam, gas, and ash emissions that drifted mainly SSW and NW. Minor ashfall was reported in the municipalities of Amecameca (20 km NW) and Tlalmanalco (30 km NW) around 2250 on 12 March. An explosion was recorded at 2351 on 13 March. Minor ashfall was reported in Amecameca the next day. The Alert Level remained at Yellow, Phase Two (middle level on a three-colour scale).

Raung – Eastern Java (Indonesia) : PVMBG reported that daily gray ash plumes rose 100-1,200 m above Raung’s summit during 10-16 March. Ash plumes drifted mainly N, NE, E, and S. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 2-km exclusion zone.

Sangay – Ecuador : IG reported a high level of activity at Sangay during 10-16 March. Seismicity was characterized by daily explosions, long-period earthquakes, and signals indicating emissions. Weather clouds often prevented visual observations of the volcano, but satellite and webcam images recorded daily ash plumes. Ash plumes were notable during 10-11 March and impacted communities downwind with ashfall. Pyroclastic flows, visible in webcam images, descended the flanks at 0950 on 10 March. The Washington VAAC stated that ash plumes rose 6.7-8.5 km (22,000-28,000 ft) a.s.l. and drifted W at lower altitudes and NW at higher altitudes. A period of explosions recorded during 0315-0545 on 11 March produced ash plumes that rose as high as 13.7 km (45,000 ft) a.s.l., or 8.5 km above the summit, and drifted NW, W, and SW. Ash plumes drifted N, NW, and W, causing significant ashfall in Guamote (42 km WNW), notable ashfall in Chambo (43 km NW), Riobamba (50 km NW), Penipe (55 km NW), and Guano (55 km NW), and minor ashfall in Colta (55 km NW), Alausí (60 km SW), and Macas. According to a social media video post the ash plumes caused widespread darkness in Riobamba for several hours. Other residents posted photos of crops covered in ash. The eruption released 31 kilotons of sulfur dioxide, the highest value recorded during the current eruptive period that began in May 2019. Heavy rainfall overnight during 11-12 March caused hot lahars in the Volcán River drainage that reached the confluence of the Upano River. Overflows in the Upano River resulting in additional lahars and debris flows. Weather clouds hindered visual observations. During 13-15 March gas-and-ash plumes rose as high has 2 km above the summit and drifted NE. Seismic signals indicating lahars were recorded on 14 March. The VAAC reported that ash plumes rose to 6-9 km (20,000-30,000 ft) a.s.l. and drifted W and WNW on 16 March.

Sheveluch - Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 5-12 March. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Sinabung – Indonesia : PVMBG reported that the eruption at Sinabung continued during 10-16 March. Avalanches of material traveled 500-1,500 m down the E, SE, and S flanks almost daily. Pyroclastic flows traveled 2-3 km down the E and SE flanks on 11 March. Ash plumes rose to 2.4-4.3 km (8,000-14,000 ft) a.s.l. and drifted SE, SW, and W during 10-12 and 15 March. The Alert Level remained at 3 (on a scale of 1-4), with a general exclusion zone of 3 km and extensions to 5 km in the SE sector and 4 km in the NE sector.

Suwanosejima – Ryukyu Islands (Japan) : JMA reported that the seismic network for Suwanosejima’s Ontake Crater detected a total of 29 explosions during 5-12 March, less than the 131 explosions recorded previous week. These events produced eruption plumes that rose as high as 1.5 km above the crater rim. Incandescence from the crater was occasionally visible at night. Rumbling was heard in a village 4 km SSW. The Alert Level remained at 2 (on a 5-level scale).

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