https://volcano.si.edu/reports_weekly.cfm The Weekly Volcanic Activity Report is a cooperative project between the Smithsonian's Global Volcanism Program and the US Geological Survey's Volcano Hazards Program. Updated by 2300 UTC every Wednesday, these notices are preliminary and subject to change as events are studied in more detail. This is not a comprehensive list of eruptions during the week, but rather a summary of activity that meet selected criteria. Carefully reviewed, detailed reports are published monthly in the Bulletin of the Global Volcanism Network. The World Organization of Volcano Observatories (WOVO) website (https://wovo.iavceivolcano.org/) lists the regional volcano observatories that have the most authoritative data for many of these events. en-us Smithsonian Institution kuhns@si.edu (Sally Kuhn Sennert) gvp@si.edu (Ed Venzke) Wed, 05 Jan 2022 02:45:19 -0500 <p>The Vanuatu Meteorology and Geo-Hazards Department (VMGD) stated that ash-and-gas plumes from Ambae had recently become more noticeable and that residents had reported minor ashfall on roofs and crops. Webcam images showed ash plumes drifting ENE at 1730 and 1830 on 2 January. At 0600 on 3 January an ash-and-steam plume rose 5 km, though only the lower portion of the plume contained ash. At 0730 that same day an ash plume rose almost 1.6 km. The Alert Level remained at 2 (on a scale of 0-5) and the public was warned to stay outside of the Danger Zone defined as a 2-km radius around the active vents in Lake Voui and away from drainages during heavy rains.</p> <p>Source: Vanuatu Meteorology and Geo-Hazards Department (VMGD)</p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_257030 Wed, 05 Jan 2022 02:45:19 -0400 -15.389 167.835 <p>The eruption at Hunga Tonga-Hunga Ha'apai continued intermittently during 29 December 2021 to 4 January 2022, though by 3 January activity had significantly decreased. Several surges of Surtseyan activity, with some periods lasting as long as 30 minutes, occurred during 28-29 December; gas, steam, and ash plumes rose at least to 12.2 km (40,000 ft) a.s.l. and drifted N, though the maximum altitude of the ash-rich portion of the plume was lower. Ashfall was local to areas around the island. Discolored water and rafts of pumice were visible in areas around the island on 30 December, and had been observed since the beginning of the eruption. Steam-and-gas plumes were visible throughout the day, interspersed with occasional tephra ejections. The plumes rose as high as 12 km (39,400 ft) a.s.l. and drifted NNE. During the morning of 31 December intermittent plumes of ash, steam, and gas rose to 3 km (10,000 ft) a.s.l. according to the Wellington VAAC, though the steam-and-gas portion of the plume rose as high as 18 km (59,000 ft) a.s.l. as stated by the Tonga Meteorological Services. The Met Services also noted that ash was no longer visible in the emissions starting around noon. Steam-and-gas plumes were occasional visible in satellite data during 1-2 January. A small ash plume rose 6-7 km (19,700-23,000 ft) a.s.l. during 2220-2230 on 2 January and drifted 10 m NE, dropping in altitude along the way. A cyclone that passed through the area during 3-4 January obscured views of the volcano. </p> <p>Sources: Tonga Geological Services, Government of Tonga ,Tonga Meteorological Services, Government of Tonga ,Wellington Volcanic Ash Advisory Center (VAAC) </p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_243040 Wed, 05 Jan 2022 02:45:19 -0400 -20.536 -175.382 <p>PVMBG reported that incandescence from Karangetang?s N crater was periodically visible during 31 December 2021 to 4 January 2022. Bluish-white emissions drifted S on 2 January. White-and-gray plumes rose as high as 200 m during 2-3 January. The Alert Level remained at 2 (on a scale of 1-4).</p> <p>Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)</p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_267020 Wed, 05 Jan 2022 02:45:19 -0400 2.781 125.407 <p>Icelandic Meteorological Office (IMO) reported that the earthquake swarm at the Krýsuvík-Trölladyngja volcanic system was ongoing with more than 19,000 earthquakes recorded during 21-28 December. Earthquakes M 4 or above totaled 14. The number and size of the earthquakes progressively decreased during 29 December 2021 to 3 January 2022; 200 events were recorded during 0000-1535 on 3 January. The seismicity was located along the same dyke system that fed the recent eruption at Geldingadalir. The Aviation Color Code remained at Orange.</p> <p>Source: Icelandic Meteorological Office (IMO)</p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_371030 Wed, 05 Jan 2022 02:45:19 -0400 63.917 -22.067 <p>OVG reported that voluminous gas plumes were visible rising from Nyiragongo and crater incandescence was visible during 3-5 January. Lava fountaining and collapses at active vents on the crater floor were observed along with a growing lava lake. Rumbling was sometimes audible. </p> <p>Source: Observatoire Volcanologique de Goma (OVG) </p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_223030 Wed, 05 Jan 2022 02:45:19 -0400 -1.520 29.250 <p>OVPF reported that the eruption at Piton de la Fournaise continued during 29 December 2021 to 4 January 2022. Weather clouds often obscured views of the vent, though visual observations were made daily. Low lava fountaining, with material rarely rising just above the crater rim, was visible on 29 December. A small mound with a vent that had grown at the base of the main cone was producing gas emissions, and lava advanced through a tube. Lava fountaining was slightly more intense during 30 December 2021 to 3 January 2022, with lava more frequently rising above the crater rim. Several breakouts of lava from the tube were noted downstream of the vent. The lava effusion rate was an estimated 2.3-9 meters per second, with peak rates of 21 meters per second, based on satellite data. Activity at the main cone decreased during 3-4 January. Lava flows within the first 100 m from the cone were an estimated 15 m thick. The flow field continued to widen but had not significantly lengthened. </p> <p>Source: Observatoire Volcanologique du Piton de la Fournaise (OVPF)</p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_233020 Wed, 05 Jan 2022 02:45:19 -0400 -21.244 55.708 <p>PVMBG reported that the eruption at Semeru continued during 29 December 2021 to 4 January 2022. Crater incandescence was visible during the nights of 31 December-4 January. At 0431 on 31 December a pyroclastic flow was generated from the end of the lava flow and an ash plume that rose 2 km above the summit drifted N. A pyroclastic flow descended the Kobokan drainage a maximum distance of 5 km SE on 1 January. Gray-and-white ash plumes rose as high as 800 m above the summit during 3-4 January and drifted in multiple directions. A pyroclastic flow traveled 5 km SE. The Alert Level remained at 3 (on a scale of 1-4). The public was warned to stay at least 500 m away from Kobokan drainages within 17 km of the summit, and other drainages originating on Semeru including the Bang, Kembar, and Sat, due to lahar, avalanche, and pyroclastic flow hazards.</p> <p>Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)</p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_263300 Wed, 05 Jan 2022 02:45:19 -0400 -8.108 112.922 <p>JMA reported that incandescence from Minamidake Crater (at Aira Caldera?s Sakurajima volcano) was visible at night during 27 December 2021 to 3 January 2022. An eruptive event at 2324 on 28 December produced an ash plume that rose 1.1 km above the crater rim. An eruptive event at 2105 on 1 January 2022 generated ash plumes that rose 1 km and ejected bombs 600-900 m away from the crater. The Alert Level remained at 3 (on a 5-level scale), and residents were warned to stay 2 km away from the crater.</p> <p>Source: Japan Meteorological Agency (JMA) </p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_282080 Wed, 05 Jan 2022 02:45:19 -0400 31.593 130.657 <p>AVO lowered both the Aviation Color Code and the Volcano Alert Level for Davidof to Unassigned on 31 December, noting that the earthquake swarm that had begun in early December had subsided. The closest seismometers are approximately 15 km E, on Little Sitkin Island. Davidof is also monitored by satellite data and remote infrasound and lightning networks.</p> <p>Source: US Geological Survey Alaska Volcano Observatory (AVO)</p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_311040 Wed, 05 Jan 2022 02:45:19 -0400 51.970 178.330 <p>The Japan Coast Guard reported that during a 27 December overflight of Fukutoku-Oka-no-Ba, observers noted that the island formed in mid-August had become smaller since 14 December, and had almost eroded below the ocean surface. No eruptive activity was observed, though brownish water spouted from the E end of the island. Yellowish-green water and a string of floating pumice, 400 m long, was circulating 5 km E. Discolored water was visible around almost the entire coast of Minami-Ioto (5 km SSW).</p> <p>Source: Japan Coast Guard</p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_284130 Wed, 05 Jan 2022 02:45:19 -0400 24.285 141.481 <p>AVO reported that slow lava effusion at Great Sitkin continued during 29 December 2021 to 4 January 2022 along with very low and persistent seismicity. Satellite images acquired on 29 December 2021 and 1 January 2022 showed that the lava flows on the W flanks had advanced. The Aviation Color Code and the Volcano Alert Level remained at Orange and Watch, respectively.</p> <p>Source: US Geological Survey Alaska Volcano Observatory (AVO)</p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_311120 Wed, 05 Jan 2022 02:45:19 -0400 52.076 -176.130 <p>PVMBG reported that during 31 December 2021 to 4 January 2022 gray-and-white ash plumes from Ibu rose 200-1,000 m above the summit. Avalanches were detected daily, though not visually observed. The Alert Level remained at a 2 (on a scale of 1-4), and the public was warned to stay at least 2 km away from the active crater and 3.5 km away on the N side.</p> <p>Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)</p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_268030 Wed, 05 Jan 2022 02:45:19 -0400 1.488 127.630 <p>KVERT reported that a thermal anomaly over Karymsky was visible in satellite images during 28-30 December. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted.</p> <p>Source: Kamchatkan Volcanic Eruption Response Team (KVERT)</p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_300130 Wed, 05 Jan 2022 02:45:19 -0400 54.049 159.443 <p>HVO reported that lava effusion intermittently continued from a vent in the lower W wall of Kilauea?s Halema`uma`u Crater during 29 December 2021 to 4 January 2022. Effusion at the vent paused on the evening of 29 December and the lake mostly crusted over, though lava oozed over the edge of the lake margins in several areas, suggesting a continuing supply of molten lava below the crust. Parts of the crusted lake overturned during 2000-2300. Occasional minor activity at the vent was visible during the morning of 30 December, and lava again began effusing form the vent at 1445. Several large lava overflows of the lake occurred in the evening and bright glow was visible in the evening sky from Volcano to lower Puna. Lava effusion was low during 1-2 January and by 0200 on 2 January the lake once again began to crust over. A large breakout along the N margin of the lake was active. Effusion ceased during 2-4 January; the lake was mostly crusted over except a few overturns N of the vent were noted. The Aviation Color Code and the Volcano Alert Level remained at Orange and Watch, respectively.</p> <p>Source: US Geological Survey Hawaiian Volcano Observatory (HVO) </p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_332010 Wed, 05 Jan 2022 02:45:19 -0400 19.421 -155.287 <p>PVMBG reported that the eruption at Lewotolok continued during 31 December 2021 to 4 January 2022. White-and-gray ash plumes that were sometimes dense rose as high as 600 m above the summit. Incandescent material was occasionally ejected from the vent up to 300 m from the vent and rumbling was sometimes heard. The Alert Level remained at 3 (on a scale of 1-4) and the public was warned to stay 3 km away from the summit crater.</p> <p>Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)</p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_264230 Wed, 05 Jan 2022 02:45:19 -0400 -8.274 123.508 <p>BPPTKG reported no notable morphological changes to Merapi?s summit lava dome, though the dome just below the SW rim had decreased about 3 m in height during 24-30 December. The estimated dome volumes were over 1.63 million cubic meters for the SW dome and just over 3 million cubic meters for the summit dome. The intensity of the seismic signals remained at high levels. As many as 175 lava avalanches traveled a maximum of 2 km SW down the Bebeng drainage, and two pyroclastic flows traveled a maximum of 1.8 km SW. The Alert Level remained at 3 (on a scale of 1-4), and the public was warned to stay 3-5 km away from the summit based on location.</p> <p>Source: Balai Penyelidikan dan Pengembangan Teknologi Kebencanaan Geologi (BPPTKG)</p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_263250 Wed, 05 Jan 2022 02:45:19 -0400 -7.540 110.446 <p>Servicio Geológico Colombiano?s (SGC) Observatorio Vulcanológico y Sismológico de Manizales reported that during 28 December 2021 to 3 January 2022 seismicity at Nevado del Ruiz was at similar levels to the week before, characterized by periods of continuous volcanic tremor, long-period events, and very-long-period earthquakes, indicating movement of fluids. These earthquakes occurred in the vicinity of Arenas Crater. Additional earthquake signals indicating rock fracturing were located in the SW, SE, and NE parts of the volcano. Several periods of ?drumbeat? seismicity, indicting growth of the lava dome, were recorded during 29-30 December and 3 January. Several low-level thermal anomalies were identified in satellite images during the week. The highest gas-and-steam plume rose about 1.2 km above the summit, recorded on 3 January. The Alert Level remained at 3 (Yellow; the second lowest level on a four-color scale).</p> <p>Source: Servicio Geológico Colombiano (SGC) </p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_351020 Wed, 05 Jan 2022 02:45:19 -0400 4.892 -75.324 <p>AVO reported that seismicity at Pavlof was elevated during 29 December 2021 to 4 January 2022 and was characterized by daily periods of tremor. Minor ash emissions were visible during 28-29 December and small explosions were occasionally recorded during 29-30 December. Thermal emissions continued to be low, and elevated surface temperatures consistent with a hot vent region were identified in satellite images during 1-3 January. During 3-4 January lava was active in an area within 100 m of the SE vent. The Volcano Alert Level remained at Watch and the Aviation Color Code remained at Orange.</p> <p>Source: US Geological Survey Alaska Volcano Observatory (AVO)</p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_312030 Wed, 05 Jan 2022 02:45:19 -0400 55.417 -161.894 <p>OVSICORI-UNA reported that at 1437 on 1 January a small eruption at Rincón de la Vieja produced a plume that rose 50 m above the crater rim. A small eruption was recorded by the seismic network at 0431 on 4 January, though weather clouds prevented visual confirmation. The amplitude of the seismic signal was similar to those recorded for events occurring in the previous few weeks. </p> <p>Source: Observatorio Vulcanologico y Sismologico de Costa Rica-Universidad Nacional (OVSICORI-UNA) </p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_345020 Wed, 05 Jan 2022 02:45:19 -0400 10.830 -85.324 <p>Instituto Geofísico del Perú (IGP) reported a daily average of 32 explosions at Sabancaya during 27 December 2021 to 2 January 2022. Gas-and-ash plumes rose as high as 2.8 km above the summit and drifted NW, W, and SW. Eight thermal anomalies originating from the lava dome in the summit crater were identified in satellite data. Minor inflation continued to be detected near Hualca Hualca (4 km N). The Alert Level remained at Orange (the second highest level on a four-color scale) and the public were warned to stay outside of a 12-km radius.</p> <p>Source: Instituto Geofísico del Perú (IGP)</p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_354006 Wed, 05 Jan 2022 02:45:19 -0400 -15.787 -71.857 <p>AVO reported that low-level eruptive activity and elevated seismicity at Semisopochnoi's North Cerberus crater continued during 29 December 2021 to 4 January 2022. Minor ash-and-steam emissions were visible in webcam images during 28-29 December. Ash plumes observed in webcam and satellite images on 31 December rose to 1.5 km (5,000 ft) a.s.l. and drifted as far as 100 km NE. Ash emissions observed in webcam images during daylight hours on 1 and 2 January were being blown down the flank by high winds. Small explosions were detected in seismic data during 2-4 January, though cloud cover obscured views. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch.</p> <p>Source: US Geological Survey Alaska Volcano Observatory (AVO)</p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_311060 Wed, 05 Jan 2022 02:45:19 -0400 51.930 179.580 <p>KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 24-31 December. Intense steam-and-gas emissions were visible. Ash plumes rose as high as 4.5 km (14,800 ft) a.s.l. and drifted 110 km NW and NE during 24-25, 27, and 30 December. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted.</p> <p>Source: Kamchatkan Volcanic Eruption Response Team (KVERT)</p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_300270 Wed, 05 Jan 2022 02:45:19 -0400 56.653 161.360 <p>JMA reported that crater incandescence at Suwanosejima's Ontake Crater was visible nightly during 27 December 2021 to 3 January 2022. The number of explosions totaled 124. The explosions produced ash plumes that rose as high as 2.2 km above the crater rim and ejected material up to 1.1 km distance from the crater. The Alert Level remained at 3 and the public was warned to stay 2 km away from the crater.</p> <p>Source: Japan Meteorological Agency (JMA) </p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_282030 Wed, 05 Jan 2022 02:45:19 -0400 29.638 129.714 <p>On 30 December the Vanuatu Meteorology and Geohazards Department (VMGD) reported that activity at Yasur continued at a high level of ?major unrest,? as defined by the Alert Level 2 status. Activity consisted of loud explosions, emissions of steam and ash, and the ejection of bombs that fell inside and around the crater area. Alert Level 2 is the middle level on a scale of 0-4. The public was reminded not to enter the restricted area within 600 m around the cone, defined by Danger Zone A on the hazard map.</p> <p>Source: Vanuatu Meteorology and Geo-Hazards Department (VMGD)</p> https://volcano.si.edu/reports_weekly.cfm https://volcano.si.edu/reports_weekly.cfm#vn_257100 Wed, 05 Jan 2022 02:45:19 -0400 -19.532 169.447