Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 7 February – 13 February 2018

Agung | Bali (Indonesia) : On 10 February PVMBG reported that activity at Agung had declined during the previous month or two leading the observatory to lower the Alert Level to 3 (on a scale of 1-4) and adjusted the exclusion zone to a 4-km radius. The report noted that the tallest eruption plume in January was 2.5 km above the crater rim, occurring on 19 January, and the last event on 24 January generated a plume that rose 1 km. The volume of erupted lava was an estimated 20 million cubic meters in December 2017, and had not significantly changed. Seismicity continued to fluctuate, though the number and magnitude of events had declined. Satellite data showed a decrease in thermal output reflective of a reduced lava flow rate. PVMBG warned that activity at Agung is still high and unstable; tiltmeter data showed low rates of inflation (GPS patterns were stable) and gas-emission data indicated magma movement at depth, though at a lower intensity compared to values measured at the end of November 2017. An event at 1149 on 13 February generated as ash plume that rose 1.5 km above the crater rim.

Aira | Kyushu (Japan) : JMA reported that very small events occurred at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 7-9 February. Crater incandescence from the summit crater was visible during 8-10 February. An event at 2201 on 11 February generated a plume that rose 1 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Ambae | Vanuatu : Based on satellite, pilot, and webcam observations, the Wellington VAAC reported that during 8-9 February ash plumes from Aoba rose to altitudes of 2.7-3 km (9,000-10,000 ft) a.s.l. and drifted N and E.

Bagana | Bougainville (Papua New Guinea) : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that during 7-8 February ash plumes from Bagana rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted NE.

Cleveland | Chuginadak Island (USA) : AVO reported that there was no evidence of significant activity at Cleveland since the last explosion was detected on 18 December 2017. The Aviation colour Code was lowered to Yellow and the Volcano Alert Level was lowered to Advisory. AVO noted that low-level unrest continued.

Dukono | Halmahera (Indonesia) : Based on analyses of satellite imagery, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 7-13 February ash plumes from Dukono rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted NE, E, and SE.

Ebeko | Paramushir Island (Russia) : Based on observations by volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, explosions during 5-8 February generated ash plumes that rose as high as 2.4 km (7,900 ft) a.s.l. Ash fell in Severo-Kurilsk on 8 February. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was identified in satellite images on 3 February. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Kilauea | Hawaiian Islands (USA) : During 7-13 February HVO reported that the lava lake continued to rise, fall, and spatter in Kilauea’s Overlook crater. Webcams recorded incandescence from a small lava pond in a pit on the W side of Pu’u ‘O’o Crater. Surface lava flows were active above and on the pali, and on the coastal plain.

Pacaya | Guatemala : INSIVUMEH reported that during 7-13 February Strombolian explosions at Pacaya’s Mackenney Crater ejected material 30 m above the main cone. Lava flows were at most 150 m long on the SW and W flanks.

Popocatepetl | Mexico : Each day during 7-13 February CENAPRED reported 25-101 emissions from Popocatépetl, with emissions during 11-13 February containing slight amounts of ash. Explosions were detected at 0130 and 2213 on 7 February, at 0457 on 8 February, at 1729 on 12 February, and at 0631 on 13 February. Minor crater incandescence was visible on the morning of 9 February, and at night during 11-12 February. The Alert Level remained at Yellow, Phase Two.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya was similar to the previous week; there was an average of 18 explosions recorded per day during 5-11 February. Seismicity was dominated by long-period events, with signals indicating emissions. Gas-and-ash plumes rose 3.9 km above the crater rim and drifted 50 km NW, SW, S, and SE. The MIROVA system detected three thermal anomalies. The sulfur dioxide flux was high, at 2,062 tons per day on 10 February. The report noted that the public should not to approach the crater within a 12-km radius.

Santa Maria | Guatemala : INSIVUMEH reported that explosions at Santa María’s Santiaguito lava-dome complex, detected by the seismic network during 7-13 February, generated ash plumes that rose as high as 700 m and drifted SW. Avalanches of material descended the E and SE flanks of the lava dome. Ash fell on La Florida ranch (5 km S) on 10 February.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 1-4 and 7 February. The Aviation colour Code remained at Orange.

Shishaldin | Fox Islands (USA) : On 7 February AVO reported that seismic and infrasound activity from Shishaldin declined to background levels during the previous month, prompting the observatory to lower the Aviation colour Code to Green and the Volcano Alert Level to Normal.

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Volcanos

Roundup of Global Volcanic Activity – New Activity for the week of 7 February – 13 February 2018

Fuego | Guatemala : INSIVUMEH reported that explosions at Fuego during 7-13 February generated ash plumes that rose as high as 1.5 km and drifted 10-12 km N, NW, SW, and S. Avalanches of material traveled down the Seca (W), Ceniza (SSW), and Taniluyá (SW) drainages on 12 February, and down the Las Lajas (SE) and Honda (E) drainages on 13 February. Ash fell in areas downwind on 13 February including Morelia (9 km SW) and Panimaché (8 km SW).

Kadovar | Papua New Guinea : RVO reported that on 9 February the lava dome at Kadovar’s SE Coastal Vent collapsed, causing 5-6 minor tsunamis, less than 1 m high, observed by residents on Blup Blup’s E and W coasts. The waves were reported at 1050, before the main collapse of the dome. In a 12 February report RVO noted that activity from Main Crater consisted of white plumes rising 20 m and drifting a few kilometers SE and weak nighttime crater incandescence.

Mayon | Luzon (Philippines) : PHIVOLCS reported that during 7-13 February activity at Mayon continued to be characterized daily by lava effusion from the summit crater, rockfalls, lava fountains, steam emissions, advancing lava flows on the flanks, and pyroclastic flows. Numerous rockfall events were generated from the front and margins of advancing lava flows. Lava fountaining was nearly continuous during 6-10 February, with around 290 lava-fountaining events recorded by the seismic network from 0557 on 5 February until around 0700 on 10 February. The events each lasted between 3 and 233 minutes, and were accompanied by rumbling sounds audible with a 10-km radius. Lava fountaining was sporadic during 11-13 February. Lava fountains during phases of both nearly continuous and sporadic activity rose as tall as 400 m, and produced steam plumes up to 2.5 km above the crater that drifted in multiple directions. Lava flows advanced to 3.3 km, 4.5 km, and 900 m in the Mi-isi (S), Bonga (SE), and Basud (E) drainages, respectively. Pyroclastic density currents traveled 4.2-4.6 km in the Mi-isi, Bonga, and Basud drainages. The Alert Level remained at 4 (on a 0-5 scale) and the public was warned to remain outside of the Danger Zone defined as an area within an 8-km radius.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 31 January – 6 February 2018

Aira | Kyushu (Japan) : JMA reported that very small events occurred at Minamidake crater (at Aira Caldera’s Sakurajima volcano) on 1 and 3 February. Crater incandescence from the summit crater was visible during 2-3 February. The Alert Level remained at 3 (on a 5-level scale).

Cleveland | Chuginadak Island (USA) : AVO reported that unrest at Cleveland continued during 31 January-6 February, though nothing significant was detected in seismic or infrasound data. Moderately elevated surface temperatures were identified in satellite images during 30-31 January; cloudy weather prevented observations the rest of the week. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Dukono | Halmahera (Indonesia) : Based on analyses of satellite imagery, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 31 January-6 February ash plumes from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted NE, E, and ESE.

Ebeko | Paramushir Island (Russia) : Based on observations by volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, explosions during 26-27 and 29-31 January generated ash plumes that rose as high as 2.5 km (8,200 ft) a.s.l. Ash fell in Severo-Kurilsk on 29 January. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that an ash plume from Karymsky was identified in satellite images drifting 80 km NE on 27 January. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Kilauea | Hawaiian Islands (USA) : During 31 January-6 February HVO reported that the lava lake continued to rise, fall, and spatter in Kilauea’s Overlook crater. Webcams recorded incandescence from a small lava pond in a pit on the W side of Pu’u ‘O’o Crater. Surface lava flows were active above and on the pali, and on the coastal plain.

Nevados de Chillan | Chile : Servicio Nacional de Geología and Minería (SERNAGEOMIN) Observatorio Volcanológico de Los Andes del Sur (OVDAS) reported that growth of the lava dome in Nevados de Chillán’s Nicanor Crater was 2,540 m3/day, determined by photos taken during overflights on 23 and 31 January. The total volume of the lava dome was an estimated 106,700 m3. A small area of deposits from collapses of the dome walls was observed. Temperatures on the surface of the dome were 305 and 480 degrees Celsius, mainly from a crack which generated the explosions. A larger explosion from a possible partial dome collapse was recorded at 1202 on 2 February, generating a gas-and-ash plume that rose about 2.5 km above the crater rim. Shock waves from the explosion were reported in the community of Las Trancas (10 km) and at the Gran Hotel Termas de Chillan (5 km). Explosive activity continued through 6 February. The Alert Level remained at Yellow, the middle level on a three-colour scale, and the public was reminded not to approach the craters within a 4-km radius.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya decreased compared to the previous week; there was an average of 22 explosions recorded per day during 29 January-4 February. Seismicity was dominated by long-period events, with signals indicating emissions. Gas-and-ash plumes rose 3.5 km above the crater rim and drifted 50 km NW, SW, and S. The MIROVA system detected two thermal anomalies. The sulfur dioxide flux was high, at 3,388 tons per day on 31 January. The report noted that the public should not to approach the crater within a 12-km radius.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images on 1 February. The Aviation colour Code remained at Orange.

Turrialba | Costa Rica : OVSICORI-UNA reported that an event at Turrialba at 0830 on 5 February generated a plume that rose 200 m above the crater rim and drifted SW. An event at 0730 on 6 February generated an ash plume that rose 1 km and drifted SW. Ashfall was reported in Goicoechea and Heredia.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week of 31 January – 6 February 2018

Fuego | Guatemala : INSIVUMEH reported that the first Strombolian eruption at Fuego in 2018 began on 31 January, after a thermal anomaly was detected in satellite images the day before. Explosions produced ash plumes that rose 1.5 km above the crater and drifted 20 km SW. Lava fountains rose 300-500 m, and fed lava flows that traveled 800 m W in the Seca (Santa Teresa) drainage and 600 m in Las Lajas (SE) and Honda (E) drainages. On 1 February the eruption style changed to Vulcanian. Pyroclastic flows mainly descended the Seca, Trinidad (S), Las Lajas, and Honda drainages. Ash plumes from explosions rose 3.2 km and drifted more than 60 km NE, SW, and W. Ashfall was recorded in areas downwind including Santa Sofía (12 km SW), Morelia (9 km SW), Panimaché I and II (8 km SW), El Porvenir (8 km ENE), Sangre de Cristo (8 km WSW), Finca Palo Verde, San Pedro Yepocapa (8 km NW), Ciudad Vieja (13.5 km NE), Antigua Guatemala (18 km NE), and W and SW Ciudad de Guatemala. CONRED reported that 2,880 people were evacuated. At 1630 INSIVUMEH noted that the Strombolian-Vulcanian eruption phase had finished, 20 hours after it had begun. Explosions continued, generating ash plumes that rose just under 1 km and drifted 15 km SW. On 2 February there were 3-5 weak explosion recorded per hour, with ash plumes rising 750 m and drifting 5-8 km W, SW, and S. Shock waves and rumbling were noted, and the lava flows remained visible. During 4-5 February ash plumes from explosions (about 5 per hour) produced ash plumes that rose 700 m and drifted W and SW. Incandescent material was ejected 200 m above the crater, causing weak avalanches of material around the crater area and in some vegetated areas.

Kadovar | Papua New Guinea : RVO reported that the eruption at Kadovar continued during 31 January-1 February at a low level. Sulfur dioxide emissions and seismicity had both decreased. Dense white vapor plumes rose 100 m from Main Crater and drifted SE. Continuous but dull glow emanated from the crater. The lava dome at the SE Coastal Vent continued to grow. A new lobe 20-30 m long grew out from the seaward side of the dome boundary, channeled by levees which had developed on the sides of the dome. White steam plumes rose 100 m above the island and drifted SE. At 1830 on 1 February a collapse of the N part of the dome produced a gray plume, vigorous steaming at the collapse site, and nighttime incandescence. The main part of the dome had bulged up, and a valley developed in between the dome and the island’s flank.

Karangetang | Siau Island (Indonesia) : In a VONA issued on 2 February, PVMBG reported an eruption at Karangetang, characterized by crater incandescence and an ash plume that rose 600 m. The Aviation colour Code was raised from Unassigned to Yellow.

Mayon | Luzon (Philippines) : PHIVOLCS reported that during 31 January-6 February daily activity at Mayon continued to be characterized by lava effusion from the summit crater, rockfalls, pyroclastic flows (31 January-1 February), ash and steam emissions, advancing lava flows on the flanks, and weak and sporadic lava fountains. Numerous rockfall events were generated by the growing and collapsing summit lava dome and from the front and margins of advancing lava flows. On 31 January pyroclastic flows traveled as far as 2 km in the Mi-isi (S), Basud (E), and Bonga (SE) drainages. White-to-light-gray ash plumes generally rose to low heights, though five events generated ash plumes that rose as high as 1 km above the crater rim. An event on 2 February also produced an ash plume that rose 1 km. The first of two lava fountaining events on 4 February lasted sporadically for 114 minutes, generated an ash plume that rose 500 m, and produced booming sounds heard within a 10-km radius. During 5-6 February high volumes of effused lava extended the lava flows in the Mi-isi, Bonga-Buyuan, and Basud drainages to 3.2, 4.5, and 3 km, respectively. The Alert Level remained at 4 (on a 0-5 scale) and the public was warned to remain outside of the Danger Zone defined as an area within an 8-km radius.

San Miguel | El Salvador : On 2 February SNET reported that seismicity at San Miguel was decreasing, along with a decrease in emissions. RSAM values fluctuating between 63 and 114 units; normal values are between 50 and 150. Small pulses of gas near the crater rim were visible.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 24 January – 30 January 2018

Agung | Bali (Indonesia) : PVMBG reported that white-and-gray plumes rose as high as 1 km above Agung’s crater rim during 24-25 January. Foggy conditions prevented visual observations of the crater during 26-30 January. The Alert Level remained at 4 (on a scale of 1-4) and the exclusion zone continued at a 6-km radius.

Aira | Kyushu (Japan) : JMA reported that very small events occurred at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 22-29 January. Crater incandescence from the summit crater was visible during the morning of 29 January. The Alert Level remained at 3 (on a 5-level scale).

Cleveland | Chuginadak Island (USA) : AVO reported that unrest at Cleveland continued during 24-30 January. A possible cold vapor plume drifted S on 24 January. Slightly elevated surface temperatures were identified in satellite images a few times during 26-30 January. Nothing significant was detected in seismic or infrasound data. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Ebeko | Paramushir Island (Russia) : Based on observations by volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, explosions during 22-23 January generated ash plumes that rose as high as 2 km (6,600 ft) a.s.l. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Etna | Sicily (Italy) : INGV reported that activity at Etna during 22-28 January was relatively unchanged compared to the previous weeks and was mainly characterized by variable-intensity gas emissions from the summit craters. Weak and sporadic ash emissions rose from the New Southeast Crater (NSEC). On 22 January ash fell in areas on the S flank and also in Catania, though the crater which produced the ash emission was unknown due to poor visibility.

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was identified in satellite images on 19 and 23 January. Gas-and-steam plumes drifted 30 km NE and NW on 21 and 25 January, and an ash plume drifted about 100 km NE on 23 January. An explosion at 1430 on 27 January generated ash plumes that rose as high as 5.2 km (17,100 ft) a.s.l. and drifted 80 km NNE, prompting KVERT to raise the Aviation colour Code to Orange (the second highest level on a four-colour scale).

Kilauea | Hawaiian Islands (USA) : During 24-30 January HVO reported that the lava lake continued to rise, fall, and spatter in Kilauea’s Overlook crater; spattering was briefly visible from the visitor overlook on 27 and 29 January. Surface lava flows were active above and on the pali, and on the coastal plain.

Reventador | Ecuador : During 24-30 January IG reported a high level of seismic activity including explosions, long-period earthquakes, harmonic tremor, and signals indicating emissions at Reventador. Steam, gas, and ash plumes rose at around 600 m above the crater rim and drifted mainly W and sometimes N. Incandescent blocks rolled as far as 800 m down the E flank and 200 m down the S and SE flanks. Weather clouds sometimes prevented visual observations.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya had decreased compared to the previous week; there was an average of 33 explosions recorded per day during 22-28 January. Seismicity was dominated by long-period events, with signals indicating emissions. Gas-and-ash plumes rose 3 km above the crater rim and drifted 50 km NW and SW. The MIROVA system detected five thermal anomalies. The sulfur dioxide flux was high, at 3,477 tons per day on 22 January. The report noted that the public should not to approach the crater within a 12-km radius.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images on 19 and 23 January. The Aviation colour Code remained at Orange.

Sinabung | Indonesia : PVMBG reported that ash plumes at Sinabung rose as high as 2.5 km above the crater during 24-30 January and drifted E, S, SW, and W. Avalanches of incandescent material traveled as far as 1.5 km down the ESE flank. A pyroclastic flow traveled 2.5 km down the ESE flank on 27 January. The Alert Level remained at 4 (on a scale of 1-4), with a general exclusion zone of 3 km and extensions of 7 km on the SSE sector, 6 km in the ESE sector, and 4 km in the NNE sector.

Turrialba | Costa Rica : OVSICORI-UNA reported that events at Turrialba at 1101 and 1427 on 26 January and at 0920 on 30 January generated plumes that rose 100-200 m above the crater rim and drifted SW.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week of 24 January – 30 January 2018

Kadovar | Papua New Guinea : RVO reported that the eruption at Kadovar continued during 23-24 January at levels similar to the previous few days. Main Crater produced light-gray to brown ash plumes that rose at most 100 m and drifted a few tens of kilometers W. Weak incandescence from Main Crater was visible at night. The lava dome at the SE Coastal Vent continued to grow and was an estimated 50 m a.s.l. (the water depth in that area was unknown) and extends out from the coast 150-200 m. The dome glowed red at night. Seismicity was low to moderate, with one high-frequency event, and 12 significant numerous small low-frequency events. Strong sulfur dioxide emissions were detected.

Kusatsu-Shiranesan | Honshu (Japan) : JMA reported that after the 23 January eruption near Motoshiranesan (the highest peak belonging to the Kusatsu-Shiranesan complex) seismicity, characterized by volcanic earthquakes and tremor, was elevated; it decreased the next day. Minor but elevated seismicity continued through 30 January, punctuated by periods of tremor. The eruption occurred from a fissure oriented E-W, located just inside the N rim of the northernmost Kagamiike Kitahi craters. JMA noted no juvenile material in the eruption deposits. The Alert Level remained at 3 (on a 5-level scale).

Mayon | Luzon (Philippines) : PHIVOLCS reported that during 23-29 January there were 2-7 daily episodes of intense and sporadic lava fountaining at Mayon, each lasting 7-74 minutes. The lava fountains rose as high as 600 m above the crater rim, and fed flows in the Mi-isi and Bonga drainages and incandescent rockfalls on the summit area. Ash plumes rose 3-5 km above the crater. As many as three pyroclastic flows each day were detected by the seismic network, and had runout distances exceeding 5 km in the Buyuan drainage. Numerous rockfall events were generated by the growing and collapsing summit lava dome and traveled into the Bonga drainage, and from the front and margins of the advancing 3-km-long lava flow on the Mi-isi drainage. The Buyuan lava flow was 1 km long. Sulfur dioxide gas emissions were between 1,252 and 2,466 tonnes/day during 23-25 January. Heavy rain triggered lahars in the Binaan drainage during 28-29 January. A cycle of energetic lava effusion with sporadic lava fountaining, and pyroclastic flows from lava-collapse events, occurred late on 29 January. The events were mostly visually obscured, and indicated by seismic data. The period began with a large-volume lava collapse at 1950 at the summit crater that generated pyroclastic flows in the Mi-isi and Bonga drainages. Lava fountaining was detected at 2016 and lasted eight minutes. This was followed by large-volume lava effusion that lasted 96 minutes, and was interspersed with sporadic lava fountaining and/or pyroclastic flows. Sporadic lava fountaining was visually and seismically detected until 2306, with lava fountains rising as high as 200 m. Ash plumes rose 1.5 km above the crater. Significant ashfall was reported in Camalig and Guinobatan, Albay before 2100, possibly resulting from the lava fountaining and pyroclastic flows.

Zaozan | Honshu (Japan) : JMA reported that tremor was detected at Zaozan on 28 and 30 January, and minor inflation at the S part of the volcano was recorded. There were 12 volcanic earthquakes detected on 31 January. JMA raised the Alert level to 2 (on a 5-level scale), noting the increased potential for a small eruption.

San Miguel | El Salvador : SNET reported that during 25-26 January seismic activity at San Miguel was slightly higher than normal, with RSAM values fluctuating between 75 and 179 units. Small pulses of gas near the crater rim were visible.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 17 January – 23 January 2018

Agung | Bali (Indonesia) : PVMBG reported that the eruption at Agung continued during 17-23 January, with gas-and-steam plumes rising from the crater punctuated by occasional ash emissions. An event at 2126 on 17 January generated a plume that rose 1.5 km above the crater rim and drifted E. An event was recorded at 1944 on 18 January, though fog prevented confirmation of a plume. At 1920 on 19 January a Strombolian event produced an ash plume that rose as high as 2.5 km and drifted E, and ejected incandescent material as far as 1 km from the crater. Incandescence emanated from the crater for about two hours after the event. White-to-gray plumes rose 500 m during 22-23 January. The Alert Level remained at 4 (on a scale of 1-4) and the exclusion zone continued at a 6-km radius.

Aira | Kyushu (Japan) : JMA reported that two of the nine events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) were explosive during 15-22 January. Plumes rose as high as 2.5 km above the crater rim, and material was ejected as far as 500 m from the crater. During field observations on 16 January scientists measured a high amount of sulfur dioxide emissions at 2,600 tons/day; the last measurement was 1,800 tons/day on 25 December 2017. The Alert Level remained at 3 (on a 5-level scale).

Cleveland | Chuginadak Island (USA) : Based on recent satellite data AVO reported on 19 January that a new lava flow had been emplaced within Cleveland’s summit crater sometime since the last observations of elevated surface temperatures on 5 January. Elevated surface temperatures were identified in satellite images during 19-22 January. No activity was detected by seismic or infrasound sensors during 20-23 January. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Ebeko | Paramushir Island (Russia) : Based on observations by volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, explosions during 11-12, 14-16, and 18 January generated ash plumes that rose as high as 3.1 km (10,200 ft) a.s.l. Minor ashfall was reported in Severo-Kurilsk during 15-16 and 18 January. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Great Sitkin | Andreanof Islands (USA) : On 18 January AVO reported that seismicity at Great Sitkin had declined over the past two months to near background levels. In addition, no significant activity was observed in satellite data during this time period and no steam plumes were noted. AVO lowered the Aviation colour Code and Volcano Alert Level to Green/Normal.

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that a small ash cloud was identified in satellite data drifting near Karymsky on 18 January. The Aviation colour Code remained at Yellow (the second lowest level on a four-colour scale).

Kilauea | Hawaiian Islands (USA) : During 17-23 January HVO reported that the lava lake continued to rise, fall, and spatter in Kilauea’s Overlook crater. Surface lava flows were active above and on the pali, and on the coastal plain. Early in the morning on 19 January rocks from the inside of Halema’uma’u crater fell into the lava lake producing a short-lived explosion of spatter and wallrock that blanketed an area around the former visitor overlook. Debris fell as far as the Halema?uma?u parking lot.

Klyuchevskoy | Central Kamchatka (Russia) : Based on satellite observations KVERT reported that a weak thermal anomaly over Klyuchevskoy was visible during 11-12, 15, and 17 January. Gas-and-steam plumes containing some ash drifted about 120 km W and E during 12 and 17-18 January. The Aviation colour Code remained at Orange.

Pacaya | Guatemala : INSIVUMEH reported that during 18-19 January Strombolian explosions at Pacaya’s Mackenney Crater ejected material 25 m above the main cone. In a special report from 20 January INSIVUMEH noted that the Strombolian activity had been cyclically building and destroying a cone within the crater. Scientists at the Observatorio del Volcan de Pacaya (OVPAC) observed a 400-m-long lava flow descending the W flank, spalling off material from the front. Strombolian explosions continued during 20-21 January, and a 200-m-long lava flow was advancing down the SW flank.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya was similar to the previous week; there was an average of 57 explosions recorded per day during 15-21 January. Seismicity was dominated by long-period events, with signals indicating emissions. Gas-and-ash plumes rose 3.3 km above the crater rim and drifted 50 km NW. The MIROVA system detected six thermal anomalies. The sulfur dioxide flux was high, at 3,410 tons per day on 19 January. The report noted that the public should not to approach the crater within a 12-km radius.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 12-19 January. The Aviation colour Code remained at Orange.

Sinabung | Indonesia : PVMBG and BNPB reported that ash plumes at Sinabung were seen rising as high as 3.5 km above the crater during 18-23 January and drifting E, SE, and W, although sometimes foggy conditions prevented visual observations. Avalanches of incandescent material traveled as far as 1.5 km down the ESE flank during 21-23 January. The Alert Level remained at 4 (on a scale of 1-4), with a general exclusion zone 3 km and extensions of 7 km on the SSE sector, and 6 km in the ESE sector, and 4 km in the NNE sector.

Turrialba | Costa Rica : OVSICORI-UNA reported that an event at Turrialba at 0000 on 22 January generated a plume that rose 500 m above the crater rim and drifted NW.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 10 January – 16 January 2018

Agung | Bali (Indonesia) : PVMBG reported that during 10-16 January gray-and-white plumes generally rose as high as 500 m above Agung’s crater rim and drifted S, SE, and E. An event at 1754 on 11 January produced an ash plume that rose 2.5 km above the crater rim and drifted NE (likely causing ashfall in areas downwind), and another event at 0723 on 15 January generated an ash plume that rose 2 km. As of 11 January BNPB estimated that 53,207 evacuees were spread out in 233 shelters. The Alert Level remained at 4 (on a scale of 1-4) and the exclusion zone continued at a 6-km radius.

Aira | Kyushu (Japan) : JMA reported that an explosive event occurred at Minamidake crater (at Aira Caldera’s Sakurajima volcano) at 1020 on 10 January, ejecting material 500-700 m from the crater. Weather clouds obscured views of the emissions. There were three events, two of which were explosive, detected during 12-15 January. The explosions ejected material as far as 500 m from the crater and produced plumes that rose as high as 1.5 km above the crater rim. The Alert Level remained at 3 (on a 5-level scale).

Kilauea | Hawaiian Islands (USA) : During 10-16 January HVO reported that the lava lake continued to rise, fall, and spatter in Kilauea’s Overlook crater. Surface lava flows were active above and on the pali, and on the coastal plain.

Klyuchevskoy | Central Kamchatka (Russia) : Based on satellite observations KVERT reported that gas-and-steam plumes from Klyuchevskoy contained some ash and drifted about 160 km NW and E during 5-6 and 8-10 January. A weak thermal anomaly was visible on 6 and 8 January. The Aviation colour Code remained at Orange.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya was similar to the previous week; there was an average of 57 explosions recorded per day during 8-14 January. Seismicity was dominated by long-period events, with signals indicating emissions. Gas-and-ash plumes rose 2.5 km above the crater rim and drifted 50 km NW and SW. The MIROVA system detected three thermal anomalies. The sulfur dioxide flux was high, at 2,071 tons per day on 12 January. The report noted that the public should not to approach the crater within a 12-km radius.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 5-12 January. Ash plumes from explosions which began at 1035 on 10 January rose to altitudes of 10-11 km (32,800-36,100 ft) a.s.l. and drifted about 900 km E during 10-11 January. KVERT briefly raised the Aviation colour Code to Red on 10 January, and then lowered it back to Orange later that day.

Suwanosejima | Ryukyu Islands (Japan) : Based on JMA notices and satellite data, the Tokyo VAAC reported that on 15 January an eruption at Suwanosejima produced a plume that rose 1.8 km (6,000 ft) a.s.l. and drifted NW.

Turrialba | Costa Rica : OVSICORI-UNA reported that an event at Turrialba at 0400 on 15 January generated a plume of unknown height due to weather conditions. Ashfall was reported in areas N of Pacayas (Pinos, Buenos Aires, and Santa Rosa de Oreamuno) and a sulfur odor was noted in Santa Rosa de Oreamuno.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week of 10 January – 16 January 2018

Kadovar | Papua New Guinea : According to Brandon Buser, just after eruption plumes started rising from a vent on the SE side of Kadovar on 5 January boats from a village on the mainland (22 km SW) and from Bam (25 km E) were sent to the island to evacuate residents. The entire population of the island (about 500 people according to a news article citing the Red Cross) was evacuated by the boats and numerous canoes to Blup Blup (15 km N). Activity escalated around midnight. The next day, at a distance of 65 km, Buser and others saw ash emissions rising from Kadovar, and at about 24 km away from the island they experienced ashfall. As they were circling the island a large event sent a large plume hundreds of feet into the air and ejected large boulders into the ocean. During another visit on 8 January Buser noted two new eruptive vents, ashfall covering everything on the village side, and wet falling ash. RVO reported that activity significantly escalated on 12 January characterized by a large blast of a substantial amount of material and “big” glowing red rocks directed to the S; the report noted that the blast was the only one reported to date. Observers on Blup Blup saw incandescence emanating from either the summit or an area out of view on the S flank. Large amounts of sulfur dioxide had been detected since 8 January, and continued to be emitted. A fracture had previously been reported on 6 January extending from the summit to the coast. When seen on 12 January, the fracture was wider and vigorous steaming was occurring at sea level. Ash plumes drifted tens of kilometers W and NW. RVO noted that the displaced villagers were getting transferred to the mainland, along with islanders from Bam, due to the relatively close proximity to the eruption plus the logistics of supplying them. Five newly-named vents were observed during an overflight conducted on 13 January: Main Crater, Western vent, and Southern vent (all three are at the summit), the SE Coastal vent, and the Southern Coastal vent. Sometimes voluminous steam and dense gray plumes rose 1 km above the Main Crater. The emissions obscured views of Southern and Western vents. The SE Coastal Vent was very active, emitting dense white steam plumes 600 m a.s.l. A possible lava dome was at the base of the plumes but showed no evidence of incandescence. The Southern Coastal Vent, located where the original fractures entered the sea, was inactive.

Mayon | Luzon (Philippines) : PHIVOLCS reported that a phreatic eruption at Mayon was detected at 1621 on 13 January, generating an ash plume that rose 2.5 km and drifted SW. The seismic network recorded the event for 1 hour and 47 minutes. Trace amounts of ash fell in Barangays Anoling (4 km S), Sua (6 km SSW), Quirangay (6 km SSW), Tumpa (7 km SW), Ilawod (10 km SSW), and Salugan (9 km SSW) of Camalig, and in Barangays Tandarora (10 km SW), Maninila (18 km S), and Travesia (10 km SW) in Guinobatan. A sulfur odor was noted by residents of Camalig. Rumbling sounds were heard by residents in Anoling. The Alert Level was raised to 2 (on a 0-5 scale). Faint crater incandescence was first observed at 2216. A phreatic eruption began at 0849 on 14 January and lasted about five minutes, and another was detected at 1143 and lasted 15 minutes. Steam-and-ash plumes from both events rose from the crater but were mostly obscured by weather clouds. Anoling residents noted rumbling sounds and a sulfur odor, and minor amounts of ash fell in Camalig. On 14 January PHIVOLCS raised the Alert Level to 3, noting a marked increase in activity characterized by three phreatic eruptions and 158 rockfall events between 1621 on 13 January and 1925 on 14 January. Bright crater incandescence was evident, signifying growth of a new lava dome and lava beginning to flow on the S flank. The report reminded residents to stay away from the 6-km-radius Permanent Danger Zone (PDZ) and the 7-km Extended Danger Zone (EDZ) on the S flank. Three collapses of material occurred on 15 January, producing rockfall or small-volume pyroclastic density currents. They were detected by the seismic network at 0941, 1005, and 1107 and lasted five, seven, and eight minutes, respectively. The first two events appeared to have been from collapses of the lava-flow front and generated ash plumes that drifted SW and ashfall in multiple Barangays including Travesia, Muladbucad Grande (8 km W), Maninila, and Masarawag (5 km W) of the Guinobatan municipality, and several Barangays in the Camalig municipality. An ash plume from the third event rose about 1 km above the crater and drifted WSW. During 15-16 January the new lava dome in the summit crater continued to effuse. Lava flows advanced 2 km down the Miisi drainage (S), and a small-volume flow was emplaced on the upper slopes of the Bonga drainage (SSE). The seismic network recorded multiple events including short-duration lava fountaining, 75 lava-collapse events corresponding to rockfalls along the front and margins of advancing lava, and short pyroclastic flows in the Miisi drainage. Ash plumes from collapse events in the summit crater produced ash plumes that rose 2 km and caused ashfall in Camalig, Guinobatan, and Polangui.

Nevados de Chillan | Chile : Servicio Nacional de Geología and Minería (SERNAGEOMIN) Observatorio Volcanológico de Los Andes del Sur (OVDAS) reported that during an overflight of Nevados de Chillán’s Volcán Arrau dome complex on 9 January scientists observed a new lava dome in the active central crater, corresponding to a new fissure first identified on 21 December 2017. Gas and water vapor rose from the fissure going across the dome surface, and the temperature of the surface was about 480 degrees Celsius. The Alert Level remained at Yellow, the middle level on a three-colour scale, and the public was reminded not to approach the craters within a 4-km radius.

San Miguel | El Salvador : SNET reported that at 1653 on 14 January and 1615 on 15 January gas-and-ash plumes from San Miguel rose no more than 300 m above the crater rim and dispersed SW. The report noted that prior to both emissions seismicity decreased and then suddenly increased.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 3 January – 9 January 2018

Aira | Kyushu (Japan) : JMA reported that very small events occurred at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 28 December 2017-4 January 2018. An event at 1744 on 6 January ejected material from Minamidake Crater as far as 900 m from the crater. An event at Showa Crater on 8 January at 0359 ejected material as far as 800 m. The Alert Level remained at 3 (on a 5-level scale).

Aoba | Vanuatu : Based on information from VGO, the Wellington VAAC reported that on 8 January ash from Aoba fell on the N and NE parts of the island; weather clouds prevented webcam and satellite observations. The next day a local observer saw an ash plume rising to an altitude of 2.1 km (7,000 ft) a.s.l. and drifting NW.

Fuego | Guatemala : INSIVUMEH reported that during 4-9 January explosions at Fuego generated ash plumes that rose as high as 1.1 km above the crater and drifted mainly 10-15 km S, SW, and W, with an occasional plume moving E or NE. Some of the explosions generated shock waves. Incandescent material was ejected 100-300 m above the crater rim, causing avalanches of material that traveled within the crater and sometimes down the Ceniza (SSW), Taniluyá (SW), and Seca (W), and Las Lajas (SE) drainages. Minor ashfall was noted in local areas including Panimaché I (8 km SW), Santa Sofía (12 km SW), Morelia (9 km SW), El Porvenir, La Rochela, and Ceylon.

Kilauea | Hawaiian Islands (USA) : During 3-9 January HVO reported that the lava lake continued to rise, fall, and spatter in Kilauea’s Overlook crater. Webcams recorded incandescence from long-active sources within Pu’u ‘O’o Crater and from a small lava pond in a pit on the W side of the crater. Surface lava flows were active above and on the pali, and on the coastal plain.

Klyuchevskoy | Central Kamchatka (Russia) : Based on satellite observations KVERT reported that gas-and-steam plumes from Klyuchevskoy contained some ash and drifted about 150 km in multiple directions during 1 and 3-4 January. A weak thermal anomaly was visible on 3 January. The Aviation colour Code remained at Orange.

Pacaya | Guatemala : INSIVUMEH reported that during 4-9 January Strombolian explosions at Pacaya’s Mackenney cone ejected material as high as 50 m above the main cone.

Popocatepetl | Mexico : CENAPRED reported that at 1348 on 1 January an explosion at Popocatépetl generated a plume with low ash content that rose 0.5 km above the crater rim and drifted SE. Each day during 3-9 January there were 110-588 emissions, some of which contained minor amounts of ash. Beginning at 2032 on 6 January Strombolian activity generated an ash, gas, and water vapor emission that rose 800 m and drifted SE, and ejected incandescent material 200-300 m onto the flanks. Explosions were recorded at 0131 and 0222 on 8 January. The Alert Level remained at Yellow, Phase Two.

Rincon de la Vieja | Costa Rica : OVSICORI-UNA reported that at 1758 on 9 January an eruption at Rincón de la Vieja produced a plume that rose 1 km above the crater rim.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya was similar to the previous week; there was an average of 41 explosions recorded per day during 1-7 January. Seismicity was dominated by long-period events, with signals indicating emissions. Gas-and-ash plumes rose 3 km above the crater rim and drifted 50 km N, NW, and W. The MIROVA system detected nine thermal anomalies. The sulfur dioxide flux was high, at 3,409 tons per day on 5 January. The report noted that the public should not to approach the crater within a 12-km radius.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 29 December 2017-5 January 2018. On 10 January satellite images captured an ash cloud, 192×132 km in dimension, from explosions rising to altitudes of 10-11 km (32,800-36,100 ft) a.s.l. and drifting 230 km NE. KVERT raised the Aviation colour Code to Red. Later that day satellite images showed an ash cloud 350×180 km in dimension drifting 400 km E; the Aviation colour Code was lowered back to Orange.

Turrialba | Costa Rica : OVSICORI-UNA reported that events at Turrialba at 0600 and 1319 on 8 January generated ash emissions that rose 400-500 m above the crater rim and drifted NW and NE, respectively. An event at 2005 generated an ash plume that rose 800 m above the crater rim and drifted SW. At 0630 on 9 January an ash plume rose 300 m above the crater rim and drifted SW. An event was recorded at 1412, though weather conditions prevented visual conformation.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week of 3 January – 9 January 2018

Agung | Bali (Indonesia) : BNPB reported that activity at Agung continued to fluctuate at a high level. Visual observations as well as seismic, deformation, and geochemistry data indicated that the eruption was continuing, though deformation data in recent days showed a stagnant trend. As of the morning of 4 January BNPB noted that there were 70,610 evacuees spread out in 240 shelters. The exclusion zone was adjusted to 6 km in all directions that same day, allowing thousands of displaced people the option to return to their homes. An estimated 17,115 people in seven villages have residences within the 6-km-radius exclusion zone. PVMBG reported that during 3-9 January gray-and-white plumes rose as high as 2 km above the crater rim and drifted in multiple directions. The Alert Level remained at 4 (on a scale of 1-4).

Kadovar | Papua New Guinea : The first confirmed historical eruption at Kadovar began around mid-day local time on 5 January, according to witnesses. The island is approximately 1.4 km in diameter with very steep slopes, located about 25 km NNE from the mouth of the Sepik River on the New Guinea mainland. The Rabaul Volcanological Observatory (RVO) warned of potential explosive activity, landslides, and resulting possible tsunamis. Aerial photos and observations from Samaritan Air flights showed dark gray ash and steam plumes rising from a crater on the SE side of the summit. It was estimated that up to 60% of the island was covered in volcanic products, which primarily appeared to be ash along with some pyroclastic flows. Ashfall was reported on Kairiru and Mushu islands (115 km WNW), Mt. Uru in Yangoru (130 km W), and Woginara (140 km W), along with locations along the W coast of the Wewak District. The NOAA/CIMSS Volcanic Cloud Monitoring system generated an alert for the ash cloud moving WNW, as imaged by S-NPP VIIRS at 0330 UTC on 5 January; Himawari-8 imagery subsequently showed that the eruption began around 0220 UTC. The Darwin VAAC issued a sequence of ash advisories starting on 5 January that noted ash moving W at an altitude of about 2.1 km (7,000 ft) a.s.l., and set the Aviation colour Code to Orange. Both discrete eruptions and continuous ongoing activity was seen in satellite imagery through 9 January, with the plume visible at distances of over 200 km W and WNW. Although initial news reports regarding the population and evacuation status were unclear, the East Sepik Governor, Allan Bird, told media on 8 January that 591 residents of Kadovar had been evacuated to Blup Blup island (about 10 km N) due to the organizational efforts of village councilors on the two islands. RVO stated that during 7-8 January ash continued to be emitted, and blown tens of kilometers WNW.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 27 December – 2 January 2018

Aira | Kyushu (Japan) : JMA reported that very small events occurred at Minamidake and Showa craters (at Aira Caldera’s Sakurajima volcano) during 25-28 December. An event at 0414 on 25 December ejected material from Minamidake Crater as far as 300 m from the crater. The Alert Level remained at 3 (on a 5-level scale).

Cleveland | Chuginadak Island (USA) : AVO reported that on 27 and 31 December 2017 and 1 January 2018 elevated surface temperatures in Cleveland’s summit crater were identified in satellite data; no other activity was noted using satellite data during 28 December 2017-2 January 2018, though weather clouds often hindered observations. Seismic and infrasound data were at background levels. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Dukono | Halmahera (Indonesia) : Based on analyses of satellite imagery, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 26 December 2017-2 January 2018 ash plumes from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted in multiple directions.

Ebeko | Paramushir Island (Russia) : Based on observations by volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, explosions on 25 December generated ash plumes that rose as high as 1.5 km (4,900 ft) a.s.l. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Kilauea | Hawaiian Islands (USA) : During 27 December 2017-2 January 2018 HVO reported that the lava lake continued to rise, fall, and spatter in Kilauea’s Overlook crater. Webcams recorded incandescence from long-active sources within Pu’u ‘O’o Crater and from a small lava pond in a pit on the W side of the crater. Surface lava flows were active above and on the pali, and on the coastal plain.

Klyuchevskoy | Central Kamchatka (Russia) : Based on satellite observations KVERT reported that gas-and-steam plumes from Klyuchevskoy contained some ash and drifted about 220 km E during 22-25 December. A weak thermal anomaly was visible on 22 December. The Aviation colour Code remained at Orange.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 22-25 December. Explosions on 26 December generated ash plumes that rose as high as 8 km (26,200 ft) a.s.l. and drifted about 300 km NE. The Aviation colour Code remained at Orange.

Sinabung | Indonesia : PVMBG reported that during 27 December 2017-2 January 2018 events at Sinabung generated ash plumes that rose as high as 3.2 km above the crater rim, and avalanches of material that traveled as far as 1.5 km E, SE, and S. Pyroclastic flows descended the E, SSE, and S flanks during 27-29 December, traveling 4.6 km SSE and 3.5 km E and S.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week of 27 December – 2 January 2018

Agung | Bali (Indonesia) : PVMBG reported that during 27 December 2017-2 January 2018 gray-and-white plumes rose as high as 2 km above Agung’s crater rim and drifted W, SW, and E. Incandescence from the crater was often observed at night. Ash fell in several local villages including Badeg, Yeha, Temukus, Besakih (11 km WSW), and Muncan (12 km SW) on 1 January, and Rendang post on 2 January. The Alert Level remained at 4 (on a scale of 1-4), and the exclusion zones continued at a general 8-km radius and 10 km in the NNE, SE, S, and SW directions.

Bezymianny | Central Kamchatka (Russia) : On 29 December KVERT reported that activity at Bezymianny was characterized by moderate gas-and-steam emissions; a lava flow likely continued to effuse onto the N flank of the lava dome. A thermal anomaly over the volcano was identified in satellite images. The Aviation Colour Code was lowered to Yellow.

Kanlaon | Philippines : PHIVOLCS reported that there were three or fewer volcanic earthquakes detected at Kanlaon each day during 27 December 2017-2 January 2018. Dense weather clouds prevented visual observations, though on 30 December a steam plume was seen rising 500 m above the crater rim and drifting SW. The Alert Level remained at 2 (on a scale of 0-5).

Pacaya | Guatemala : INSIVUMEH reported continuing Strombolian explosions at Pacaya’s Mackenney cone during 31 December 2017-1 January 2018.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 20 December – 26 December 2017

Aira | Kyushu (Japan) | 31.593°N, 130.657°E : JMA reported that very small events occurred at Minamidake Crater (at Aira Caldera’s Sakurajima volcano) during 18-25 December. An event at 0514 on 25 December ejected material as far as 500 m from the crater. The Alert Level remained at 3 (on a 5-level scale).

Bagana | Bougainville (Papua New Guinea) : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that during 25-26 December ash plumes from Bagana rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted NE.

Dukono | Halmahera (Indonesia) : Based on analyses of satellite imagery, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 20-25 December ash plumes from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted NE, E, SE, and S.

Ebeko | Paramushir Island (Russia) : KVERT reported that on 16 December an ash plume from Ebeko was identified in satellite images drifting about 15 km SSW. A thermal anomaly was also visible. Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E, observed ash plumes from explosions rising as high as 3.5 km (7,500 ft) a.s.l. during 18-19 and 21-22 December. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that an ash plume from Karymsky was identified in satellite data drifting 114 km ENE on 14 December. No further ash emissions were noted afterwards; the Aviation colour Code was lowered to Yellow (the second lowest level on a four-colour scale) on 24 December.

Kilauea | Hawaiian Islands (USA) : During 20-26 December HVO reported that the lava lake continued to rise, fall, and spatter in Kilauea’s Overlook crater. Webcams recorded incandescence from long-active sources within Pu’u ‘O’o Crater and from a small lava pond in a pit on the W side of the crater. Surface lava flows were active above and on the pali, and on the coastal plain.

Nevados de Chillan | Chile : On 19 December Servicio Nacional de Geología and Minería (SERNAGEOMIN) Observatorio Volcanológico de Los Andes del Sur (OVDAS) reported an increase in activity at Nevados de Chillán’s Volcán Arrau dome complex during the previous three days. The activity was characterized by minor explosions occurring at a rate of four events per hour. Gas-and-tephra plumes rose 1 km above the crater rim. POVI reported that on 20 December explosions ejected incandescent material above the crater rim. The Alert Level remained at Yellow, the middle level on a three-colour scale, and the public was reminded not to approach the craters within a 3-km radius.

Oraefajokull | Iceland : On 22 December IMO reported that activity at Öræfajökull had been fairly stable during the previous weeks, though still above background levels; the Aviation colour Code remained at Yellow. In December the largest earthquake detected was a M2.5, but most events were smaller than M1. Earthquakes were located close to the caldera at depths between 2 and 10 km.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite images during 19-21 December. The Aviation colour Code remained at Orange.

Sinabung | Indonesia : Based on observations by PVMBG, satellite images, and model data, the Darwin VAAC reported ash plumes from Sinabung during 20-23 December. The plumes rose 3.7-4.9 km (12,000-16,000 ft) a.s.l. during 20-21 December and drifted E and SW; weather clouds prevented estimates of plume altitudes on the other days.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week of 20 December – 26 December 2017

Agung | Bali (Indonesia) : PVMBG reported that during 20-26 December gray-and-white plumes rose as high as 2 km above Agung’s crater rim and drifted W and E; weather clouds and fog sometimes prevented visual observations. Incandescence from the crater was sometimes observed at night. BNPB reported that during 22-23 December events generated dense gray ash plumes that rose as high as 2.5 km above the crater rim and drifted NE. Ash fell on the flanks and in Tulamben, Kubu. As of 25 December there were 71,045 evacuees spread out in 239 shelters. The Alert Level remained at 4 (on a scale of 1-4), and the exclusion zones continued at a general 8-km radius and 10 km in the NNE, SE, S, and SW directions.

Bezymianny | Central Kamchatka (Russia) : KVERT reported that ash plumes from the 20 December explosive eruption at Bezymianny rose as high as 15 km (49,200 ft) a.s.l. and drifted 320 km NE. A thermal anomaly over the volcano was identified in satellite images during 21-22 December. The Aviation colour Code remained at Orange.

Kanlaon | Philippines : PHIVOLCS reported that during 19-20 December there were 412 volcanic earthquakes detected at Kanlaon. A low-energy, explosion-type earthquake was detected at 0233 on 21 December associated with gas emissions from the summit area. Later in the day steam plumes rose 400 m and drifted NE. The number of daily volcanic earthquakes increased to 957 the next day and then decreased to less than 20 per day during 22-23 December; the daily count increased to 382 and 776 events on 24 and 25 December, respectively, and then decreased to 82 on 26 December. White plumes rose 300 m and drifted NE, NW, and SW on 21 December, and 700 m on 26 December; weather clouds prevented views on the other days. The Alert Level remained at 2 (on a scale of 0-5).

Klyuchevskoy | Central Kamchatka (Russia) : Based on satellite observations KVERT reported that gas-and-steam plumes from Klyuchevskoy contained some ash and drifted about 140 km E during 16-19 December. A weak thermal anomaly was visible on 16 December. The Aviation colour Code remained at Orange.

Pacaya | Guatemala : INSIVUMEH reported that during 24-26 December Strombolian explosions at Pacaya’s Mackenney cone ejected material as high as 50 m above the main cone. A 100-m-long lava flow on the W flank was visible.