Volcanos

Global Volcanic Activity – New Activity for the week of 6 November – 12 November 2019

Cleveland | Chuginadak Island (USA) : Highly elevated surface temperatures identified in satellite data indicated that slow lava effusion in Cleveland’s summit crater may have begun during 7-8 November. AVO raised the Volcano Alert Level to Watch and the Aviation colour Code to Orange. Robust steaming was visible in satellite and webcam images on 7 November.

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images on 6 November. The Aviation colour Code remained at Orange.

Manam | Papua New Guinea : RVO reported that at 1330 on 2 November a single large explosion at Manam generated a dense dark ash plume that rose 1 km above the summit and drifted NW. A shock wave was felt at the Bogia Government station (about 40 km SE) about 1 minute later. RSAM values on 6 November fluctuated between 250 and 360 units but began to increase around 1430 and triggered alerts around 1445. Values continued to increase and reached 400-500 units, heralding an eruption which began during 1600-1630. A gray ash plume rose 1 km and drifted NW. Incandescent material ejecting from the vent was visible at the start of the eruption and became more visible as the evening grew darker. The eruption peaked in intensity around 1930, then declined and ceased during 2100-2200.

Popocatepetl | Mexico : During an overflight of Popocatépetl on 5 November CENAPRED scientists, researchers from Instituto de Geofísica de UNAM, and members of the Coordinación Nacional de Protección Civil observed lava dome number 85 in the bottom of the inner summit crater. The dome was 210 m in diameter, 80 m thick, and had an irregular surface. The inner crater remained 350 m in diameter and was 90 m deep. CENAPRED reported that each day during 6-12 November there were 58-148 steam-and-gas emissions, some of which contained ash. Explosions at 0300 and 0501 on 6 November and at 0023 and 0655 on 7 November ejected incandescent tephra onto the upper flanks. Five more explosions were detected on 6 November. Eruptive events at 0858 and 0941 on 9 November generated ash plumes that rose 2 km above the crater rim and drifted NW; between those two ash emissions explosions were recorded at 0923 and 2055. Explosions on 10 November were recorded at 0648 and 1636. An explosion at 2203 on 11 November ejected incandescent tephra as far down the E flank as 1.5 km and generated an ash plume that rose 2 km and drifted NE. The Alert Level remained at Yellow, Phase Two (middle level on a three-colour scale).

Shishaldin | Fox Islands (USA) : AVO reported that the eruption at Shishaldin continued at variable levels during 5-12 November. Periods of high-amplitude tremor during 5-6 November were likely related to increased lava effusion and fountaining, though weather clouds prevented visual confirmation. Intermittent advancement of active lava flows and lahars on the N flank were confirmed in RADAR data, and by 7 November the lava flow was 1.3 km long and the debris flow runout was 5 km. Seismic tremor was low during 8-9 November suggesting lava effusion was less likely; weather cloud cover continued to obscure views, though elevated surface temperatures were sometimes detected during brief periods of clear weather. Activity significantly increased during 10-11 November with lava fountaining visible in webcam views throughout the evening and night. Strongly elevated surface temperatures at the summit and along the flanks were visible in satellite data. Ash emissions reported by pilots and visible on webcam images rose as high as 3.7 km (12,000 ft) a.s.l. and drifted N. Activity decreased during 11-12 November. Strongly elevated surface temperatures were consistent with cooling lava flows. Seismicity decreased during the evening of 11 November and remained low. Minor steam-and-ash emissions were visible in webcam images. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Volcanos

Global Volcanic Activity – New Activity for the week of 8 May – 14 May 2019

Asosan | Kyushu (Japan) : JMA reported that incandescence from Asosan’s Nakadake Crater was visible during 9-10 May. A small eruption on 9 May produced a plume that rose 900 m above the crater rim. Four small eruptions on 12 May generated plumes that rose to a maximum height of 1.4 km. A plume from an eruption on 13 May rose 200 m. Sulfur dioxide emissions were 3,600 tons per day on 10 May, and 1,700 tons per day on 13 May. The Alert Level remained at 2 (on a scale of 1-5).

Sangay | Ecuador : IG reported that two M2 seismic events, recorded at 0028 and 0116 on 10 May and located 3.5-9 km below Sangay’s S and W flanks, possibly corresponded to explosive activity. Four thermally elevated pixels were identified in satellite data at 0124. A small emission was visible drifting W.

Sinabung | Indonesia : PVMBG reported that an eruption at Sinabung was recorded at 2039 on 11 May. An ash plume was not visible due to weather conditions, although crater incandescence was noted. An eruption at 1233 on 12 May was recorded by the seismic network; foggy weather prevented visual confirmation. The Alert Level remained at 4 (on a scale of 1-4), with a general exclusion zone of 3 km and extensions to 7 km on the SSE sector, 6 km in the ESE sector, and 4 km in the NNE sector.

Volcanos

Global Volcanic Activity – Ongoing Activity for the week of 6 March – 12 March 2019

Agung | Bali (Indonesia) : PVMBG reported that at 0452 on 4 March an event at Agung was recorded for just under three minutes and produced ashfall in Besakih (7 km SW) around 0615. No ash plume was visible although foggy conditions prevented views of the summit. An event that began at 0047 on 9 March lasted for 3 minutes and 50 seconds, and produced an ash plume that drifted E. The Alert Level remained at 3 (on a scale of 1-4) with the exclusion zone set at a 4-km radius.

Aira | Kyushu (Japan) : JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was occasionally visible during 4-11 March. Occasional small events and three explosions were detected during 8-11 March. Plumes rose as high as 1.9 km. The Alert Level remained at 3 (on a 5-level scale).

Dukono | Halmahera (Indonesia) : Based on satellite images, wind model data, and ground observations, the Darwin VAAC reported that during 5-9 and 11-12 March ash plumes from Dukono rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted WSW, SW, S, and SE. The Alert Level remained at 2 (on a scale of 1-4), and visitors were warned to remain outside of the 2-km exclusion zone.

Karangetang | Siau Island (Indonesia) : PVMBG reported that during 4-10 March a low rate of lava effusion continued at Karangetang’s Kawah Dua (North Crater) as evident by avalanches in the Malabuhe River drainage on the NW flank. White plumes rose as high as 500 m above the rims of the summit craters during 4-12 March. The Darwin VAAC reported that on 7 March an ash plume rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted SW. The Alert Level remained at 3 (on a scale of 1-4), and residents were warned to remain outside of the 2.5-km exclusion zone around the N and S craters, and additionally within 3 km WNW and 4 km NW.

Kerinci | Indonesia : PVMBG reported that at 1850 on 7 March a brown ash emission rose 150 m above the rim of Kerinci summit vent and drifted NE. Ash also drifted down the SE and E flanks. Another brown ash emission was observed at 1209 on 8 March rising 700 m and drifting W. Brown ash emissions at 1607 on 10 March and 0919 on 11 March rose 300 m and 500 m, respectively, and drifted NE. Seismicity was dominated by volcanic tremor during 7-11 March.

Manam | Papua New Guinea : The Darwin VAAC reported that during 5-6 March ash plumes from Manam rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted E based on satellite data and ground-based observations. A significant thermal anomaly was also visible in satellite images, and seismicity was elevated.

Merapi | Central Java (Indonesia) : PVMBG reported that during 1-12 March white-and-gray emissions of variable density rose as high as 1 km above Merapi’s summit. The volume of the lava dome was 470,000 cubic meters on 5 March, as estimated from drone photographs, and relatively unchanged from the previous weeks. There were no apparent morphological changes; most of the extruded lava fell into the upper parts of the Gendol River drainage on the SE flank. Block-and-ash flows traveled 500-1,900 m down the Gendol drainage on 2, 3, and 7. The Alert Level remained at 2 (on a scale of 1-4), and residents were warned to remain outside of the 3-km exclusion zone.

Nevados de Chillan | Chile : ONEMI and SERNAGEOMIN reported that an explosive event at Nevados de Chillán’s Nicanor Crater was recorded at 0845 on 8 March and was associated with a long-period earthquake signal. The explosion ejected and deposited material in areas around the crater, mainly to the N, and produced a plume that rose 2.7 km above the crater rim. The Alert Level remained at Orange, the second highest level on a four-colour scale, and residents were reminded not to approach the crater within 3 km. ONEMI maintained an Alert Level Yellow (the middle level on a three-colour scale) for the communities of Pinto, Coihueco, and San Fabián.

Poas | Costa Rica : OVSICORI-UNA reported that, although weather conditions often prevented visual observations of Poás during 7-8 and 10 March, gas plumes sometimes containing ash were observed rising as high as 500 m above the crater rim and drifting SW. A sulfur odor and ashfall were reported in Naranjo and Grecia (16 km SW).

Sabancaya | Peru : Instituto Geofísico del Perú (IGP) and Instituto Geológico Minero y Metalúrgico (INGEMMET) reported that an average of 15 explosions per day occurred at Sabancaya during 4-10 March. Long-period seismic events were recorded, and hybrid earthquakes were infrequent and of low magnitude. Gas-and-ash plumes rose as high as 2.8 km above the crater rim and drifted 20 km SW, W, and NW. MIROVA detected four thermal anomalies, and on 3 March the sulfur-dioxide gas flux was high at 3,360 tons per day. The report noted that the public should not approach the crater within a 12-km radius.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch’s lava dome was identified daily in satellite images during 1-8 March. Strong gas-and-steam emissions containing variable amounts of ash rose to altitudes of 3.5-4 km (11,500-13,100 ft) a.s.l. and drifted about 50 km E on 1 March. On 9 March explosions generated ash plumes that rose 10-11.2 km (32,800-36,700 ft) a.s.l. and drifted 70 km NW and N, prompting KVERT to raise the Aviation colour Code to Red (the highest level on a four-colour scale). Early on 10 March the Aviation colour Code was lowered to Orange. Ash plumes continued to rise from the crater, to an altitude of 8 km (26,200 ft) a.s.l., and drift 375 km N. Later that day gas-and-steam plumes with some ash rose as high as 4.5 km (14,800 ft) a.s.l. and drifted 15 km NE. On 11 March an ash plume rose as high as 4.7 km (15,400 ft) a.s.l. and drifted 70 km SE.

Suwanosejima | Ryukyu Islands (Japan) : JMA reported that crater incandescence at Suwanosejima’s Ontake Crater was visible at night during 1-8 March. Small events were occasionally recorded, generating plumes that rose as high as 600 m above the crater rim. The Alert Level remained at 2 (on a 5-level scale).

Turrialba | Costa Rica : OVSICORI-UNA reported that during 9-12 March plumes of gas sometimes containing small amounts of ash rose as high as 1 km above Turrialba’s crater rim

Volcanos

Global Volcanic Activity – Ongoing Activity for the week of 27 February – 5 March 2019

Aira | Kyushu (Japan) : JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was occasionally visible during 25 February-4 March. There were four events and seven explosive events. Plumes rose as high as 2.3 km, and material as ejected as far as 1.1 km from the crater. The Alert Level remained at 3 (on a 5-level scale).

Dukono | Halmahera (Indonesia) : Based on satellite and wind model data, ground observations, and notices from PVMBG, the Darwin VAAC reported that during 27 February-5 March ash plumes from Dukono rose to altitudes of 2.1-2.4 km (7,000-8,000 ft) a.s.l. and drifted in multiple directions. On 28 February two plumes rising from the crater were visible; a northern plume was identified in satellite images and a southern plume rising to less than 1.5 km (5,000 ft) a.s.l. was reported by a ground observer. The Alert Level remained at 2 (on a scale of 1-4), and visitors were warned to remain outside of the 2-km exclusion zone.

Ibu | Halmahera (Indonesia) : The Darwin VAAC reported that on 28 February an ash plume from Ibu was identified in satellite images drifting N at an altitude of 2.1 km (7,000 ft) a.s.l. The Alert Level remained at 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.

Karangetang | Siau Island (Indonesia) : PVMBG reported that during 25 February-5 March a low rate of lava effusion continued at Karangetang’s Kawah Dua (North Crater). White plumes rose as high as 500 m above the summit crater rims. The Darwin VAAC reported that on 27 February a pilot observed an ash plume rising to an altitude of 1.8 km (6,000 ft) a.s.l. and drifting SE. The Alert Level remained at 3 (on a scale of 1-4), and residents were warned to remain outside of the 2.5-km exclusion zone around the N and S craters, and additionally within 3 km WNW and 4 km NW.

Manam | Papua New Guinea : The Darwin VAAC reported that on 1 and 5 March ash plumes from Manam were identified in satellite images rising to an altitude of 3 km (10,000 ft) a.s.l. and drifting SE, ESE, and E.

Merapi | Central Java (Indonesia) : PVMBG reported that during 22 February-5 March the volume of the lava dome in Merapi’s summit crater had not changed since the last measurement of 466,000 cubic meters estimated on 21 February. There were no apparent morphological changes; most of the extruded lava fell into the upper parts of the Gendol River drainage on the SE flank. Block-and-ash flows traveled 600-1,100 m down the Gendol drainage on 25 and 27 February, and on 2 March as many as 10 traveled as far as 2 km. Incandescent avalanches were visible at night. The Alert Level remained at 2 (on a scale of 1-4), and residents were warned to remain outside of the 3-km exclusion zone.

Nevados de Chillan | Chile : ONEMI and SERNAGEOMIN reported that an explosive event at Nevados de Chillán’s Nicanor Crater was recorded at 2323 on 1 March and was associated with a long-period earthquake signal. The explosion ejected high-temperature incandescent material deposited in areas around the crater, and likely destroyed part of the lava dome. The Alert Level remained at Orange, the second highest level on a four-colour scale, and residents were reminded not to approach the crater within 3 km. ONEMI maintained an Alert Level Yellow (the middle level on a three-colour scale) for the communities of Pinto, Coihueco, and San Fabián.

Santa Maria | Guatemala : INSIVUMEH reported that during 1-5 March as many as four explosions per hour at Santa María’s Santiaguito lava-dome complex generated white plumes with ash that rose 500-700 m above the domes and drifted SE and SW. Avalanches of material descended the E and SE flanks of the lava dome. An explosion at 2155 on 4 March was heard in areas as far away as 10 km W, SW, S, and SE. The event ejected incandescent material 100 m high, produced ashfall around the volcano, and generated avalanches that traveled down the E and SE dome flanks reaching the base.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch’s lava dome was identified daily in satellite images during 22 February-1 March. Strong gas-and-steam emissions contained variable amounts of ash on 21, 25, and 27 February, and rose 4-5 km (13,100-16,400 ft) a.s.l. and drifted 100 km SW and E. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Suwanosejima | Ryukyu Islands (Japan) : JMA reported that crater incandescence at Suwanosejima’s Ontake Crater was visible at night during 22 February-1 March. Small events were occasionally recorded, generating plumes that rose as high as 900 m above the crater rim. The Alert Level remained at 2 (on a 5-level scale).

Turrialba | Costa Rica : OVSICORI-UNA reported that an event at Turrialba at 1050 on 28 February generated a plume that rose 500 m above the crater rim and drifted SW. Some additional ash pulses were recorded that day. An event at 0444 on 1 March produced a plume that rose 200 m and drifted NE. A period of continuous emissions rising 200-300 m was recorded during 2-4 March; the plumes contained minor amounts of ash at least during 2-3 March.

Volcanos

Global Volcanic Activity – Ongoing Activity for the week of 6 February – 12 February 2019

Agung | Bali (Indonesia) : PVMBG reported that a 97-second-long explosive event at Agung began at 0012 on 8 February. A plume was not visible, though webcams recorded crater incandescence. The Alert Level remained at 3 (on a scale of 1-4) with the exclusion zone set at a 4-km radius.

Aira | Kyushu (Japan) : JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was visible during 4-12 February. At 1919 on 7 February an event generated a plume that rose 1.3 km above the crater rim and ejected material 1.3-1.7 km from the crater. During 8-12 February there were four events, three of which were explosive. Plumes rose as high as 1.9 km, and boulders were ejected as far as 900 m from the crater. The Alert Level remained at 3 (on a 5-level scale).

Copahue | Central Chile-Argentina border : On 6 February OVDAS-SERNAGEOMIN lowered the Alert Level for Copahue to Green, the lowest level on a four-colour scale, noting the return of the crater lake and infrequent surficial activity. In addition, data from the geodetic monitoring network showed only slight deformation during the previous three months. ONEMI lowered the Alert Level to Green (the lowest level on a three-colour scale) for the municipality of Alto Biobío.

Dukono | Halmahera (Indonesia) : Based on satellite data, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 9-10 and 12 February ash plumes from Dukono rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted SW. The Alert Level remained at 2 (on a scale of 1-4), and visitors were 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 2-8 February that sent ash plumes to 2.3 km (7,500 ft) a.s.l. Ash fell in Severo-Kurilsk on 4 February. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Etna | Sicily (Italy) : INGV reported that during 6-10 February webcams at Etna recorded gas emissions from New Southeast Crater (NSEC) and Voragine Crater, and occasional ash clouds from Northeast Crater (NEC); inclement weather prevented observations during 4-5 February. From the beginning of the afternoon on 6 February discrete ash emissions rose from NEC. The ash emissions were continuous from about 2215 on 7 February to 1015 on 8 February, producing relatively diffuse ash plumes that drifted S and then SE. Ash fell in Nicolosi (14 km S) and Pedara (15 km SSE). A diffuse ash plume drifted SW on 9 February.

Ibu | Halmahera (Indonesia) : PVMBG reported that during 5-12 February dense white-to-gray plumes from Ibu rose 200-800 m above the summit and drifted E, S, and W. Foggy conditions occasionally prevented visual observations. The Alert Level remained at 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.

Kadovar | Papua New Guinea : According to Brad Scott of GeoNet, the Royal New Zealand Air Force released photos of a plume rising from Kadovar at 1640 on 10 February.

Merapi | Central Java (Indonesia) : PVMBG reported that during 1-11 February the volume of the lava dome in Merapi’s summit crater was about the same as the previous week’s estimate of 461,000 cubic meters, and there were no apparent morphological changes. Most of the extruded lava fell into the upper parts of the Gendol River drainage and the SE flank. On 7 February a pyroclastic flow traveled 2 km down the Gendol drainage. The Alert Level remained at 2 (on a scale of 1-4), and residents were warned to remain outside of the 3-km exclusion zone.

Nevados de Chillan | Chile : ONEMI and SERNAGEOMIN reported that during 5-12 February growth of the lava dome in Nevados de Chillán’s Nicanor Crater was very slow (0.003-0.004 cubic meters per second). White water vapor emissions, occasionally grayish from included tephra, rose as high as 1 km and drifted in multiple directions. Crater incandescence was recorded by a webcam each day. The Alert Level remained at Orange, the second highest level on a four-colour scale, and residents were reminded not to approach the crater within 3 km. ONEMI maintained an Alert Level Yellow (the middle level on a three-colour scale) for the communities of Pinto, Coihueco, and San Fabián.

Pacaya | Guatemala : INSIVUMEH reported that during 7-12 February Strombolian explosions at Pacaya’s Mackenney Crater ejected material as high as 25 m above the crater rim. Multiple lava flows traveled 10-250 m down the NW flank, advancing towards Cerro Chino, and on the E flank. Minor avalanches of material from lava-flow fronts descended the flanks.

Rincon de la Vieja | Costa Rica : OVSICORI-UNA reported possible events at Rincón de la Vieja at 1906 and 1950 on 5 February and at 0120 on 6 February. An event at 0000 on 6 February was also recorded; the report noted that poor weather conditions prevented visual observations of the crater.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that an average of 26 explosions per day occurred at Sabancaya during 4-10 February. Long-period seismic events were recorded, and hybrid earthquakes were infrequent and of low magnitude. Although weather conditions sometimes prevented visual observations, gas-and-ash plumes were seen rising as high as 3 km above the crater rim and drifted 30 km S and SW. MIROVA detected one thermal anomaly. The report noted that the public should not approach the crater within a 12-km radius.

Santa Maria | Guatemala : INSIVUMEH reported that during 7-12 February explosions at Santa María’s Santiaguito lava-dome complex generated ash plumes that rose 500-700 m and drifted E and SW, causing ashfall on the flanks. Avalanches of material descended the NE, E, and SE flanks of the lava dome.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that during 2-8 February Sheveluch’s lava dome continued grow, extruding blocks on the N side, and producing hot avalanches and fumarolic plumes. A thermal anomaly was identified in satellite images daily. Video and satellite data recorded gas-and-steam plumes with some ash content rising to 4-5 km (13,100-16,400 ft) a.s.l. and drifted 105 km E and W. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale). Suwanosejima | Ryukyu Islands (Japan) : JMA reported that crater incandescence at Suwanosejima’s Ontake Crater was visible during 1-8 February. Were small events were occasionally recorded, generating plumes that rose as high as 900 m above the crater rim. The Alert Level remained at 2 (on a 5-level scale).

Turrialba | Costa Rica : OVSICORI-UNA reported that a period of sporadic ash emissions from Turrialba began at 0540 on 8 February and lasted more than one hour. The activity produced ash plumes that rose no more than 200 m above the vent rim. A very small ash emission was visible on 11 February.

Volcanos

Global Volcanic Activity – New Activity for the week of 6 February – 12 February 2019

Karangetang | Siau Island (Indonesia) : On 8 February PVMBG reported that lava from Karangetang’s Kawah Dua (North Crater) continued to advance over 3.5 km down the Malebuhe River drainage on the NW flank into the ocean. Levees had formed at the margins channeling the lava down the middle of the flow. Avalanches from the edges of the flow generated brown and gray plumes. A lava delta was building out into the ocean and generating a dense steam plume. Drone footage acquired on 9 February showed that the flow was about 160 m wide where it crossed a road (about 210 m from the coast) and about 140 m wide at the coast. Seismicity remained high. The Alert Level remained at 3 (on a scale of 1-4), and residents were warned to remain outside of the 2.5-km exclusion zone around the N and S craters, and not enter within 3 km WNW and 4 km NW.

Poas | Costa Rica : OVSICORI-UNA reported that seismic and infrasound data indicated multiple events at Poás during 7-8 February. On 8 February events were centered at vent A (Boca Roja) and produced plumes that rose no higher than 200 m and drifted SW. A sulfur dioxide odor was reported in areas downwind including San Jose de Naranjo, Grecia (16 km SW), Poás, Sarchá, Naranjo, and Atenas (32 km SW). Incandescence in the crater began to be visible at 0151 on 11 February. Passive ash emissions rose 200 m and drifted SW.

Volcanos

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

Aira | Kyushu (Japan) : JMA reported that during 22-26 October seven events at Minamidake crater (at Aira Caldera’s Sakurajima volcano) produced eruption plumes that rose as high as 1.6 km above the crater rim. Small scale events were occasionally detected through 29 October. The Alert Level remained at 3 (on a scale of 1-5).

Bezymianny | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Bezymianny was identified in satellite images during 20 and 22-25 October. Gas-and-steam emissions continued to rise from the crater. The Aviation colour Code remained at Yellow (the second lowest level on a four-colour scale).

Dukono | Halmahera (Indonesia) : Based on satellite data, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 24-28 October ash plumes from Dukono rose to altitudes of 1.5-1.8 km (5,000-6,000 ft) a.s.l. and drifted E and NE.

Ebeko | Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 19-26 October that sent ash plumes to 4.7 km (15,400 ft) a.s.l. Ash plumes drifted eastward, and caused ashfall in Severo-Kurilsk during 19-20 and 23-24 October; ash plumes drifted about 80 km E on 20 October. A thermal anomaly was visible in satellite images on 24 October. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Kadovar | Papua New Guinea : The Darwin VAAC reported that during 29-30 October intermittent ash plumes from Kadovar rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted SW, S, and SE.

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was last identified in satellite images on 28 September, and an ash plume was last visible on 30 September. The volcano was either quiet or obscured by weather clouds during 1-25 October. On 26 October the Aviation colour Code was lowered to Yellow (the second lowest level on a four-colour scale).

Krakatau | Indonesia : Based on satellite data, the Darwin VAAC reported that during 24-28 October ash plumes from Anak Krakatau rose to altitudes of 0.9-2.1 km (3,000-7,000 ft) a.s.l. and drifted SW, NW, and N. The Alert Level remained at 2 (on a scale of 1-4); residents and visitors were warned not to approach within 2 km of the crater.

Merapi | Central Java (Indonesia) : PVMBG reported that during 19-25 October the lava dome in Merapi’s summit crater grew slowly at a rate of 6,100 cubic meters per day, similar to the previous week. By 21 October the volume of the dome, based on photos from the SE sector, was an estimated 219,000 cubic meters. White emissions of variable density rose a maximum of 50 m above the summit. The Alert Level remained at 2 (on a scale of 1-4), and residents were warned to remain outside of the 3-km exclusion zone.

Nevado del Ruiz | Colombia : Servicio Geológico Colombiano’s (SGC) Observatorio Vulcanológico y Sismológico de Manizales reported that during 24-30 October seismicity at Nevado del Ruiz continued to indicate unrest. Seismicity increased during 26-27 October, with signals concentrated in an area 4.6 km WSW of Arenas Crater at depths of 4-6 km. Plumes of water vapor, ash, and gas continued to rise from the volcano, and on 26 October a plume rose as high as 1.5 km above the crater rim. A weak thermal anomaly was identified in satellite data. The Alert Level remained at 3 (Yellow; the second lowest level on a four-colour scale).

Piton de la Fournaise | Reunion Island (France) : OVPF reported that on 24 October satellite observations of Piton de la Fournaise suggested minimal change to the lava-flow field. During 25-26 October a breakout from the main tube emerged about 1 km downstream from the vent and remained visible through 28 October. Weather conditions prevented views on 29 October.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that an average of 30 explosions per day occurred at Sabancaya during 22-28 October. Hybrid earthquakes were infrequent and of low magnitude, and long-period events were detected. Gas-and-ash plumes rose as high as 3.4 km above the crater rim and drifted 40 km SE, E, and NE. MIROVA detected five thermal anomalies, and on 27 October the sulfur-dioxide gas flux was high at 2,671 tons per day. The report noted that the public should not approach the crater within a 12-km radius.

Semisopochnoi | United States : AVO reported that an eruptive event at Semisopochnoi began at 2047 on 25 October based on seismic data; strong volcanic tremor lasted about 20 minutes and was followed by 40 minutes of weak tremor pulses. A weak infrasound signal was detected by instruments on Adak Island (260 km SE). The Aviation colour Code was raised to Orange (the second highest level on a four-colour scale) and Volcano Alert Level was raised to Watch (the second highest level on a four-level scale). A dense meteorological cloud deck prevented observations below 3 km (10,000 ft) a.s.l.; a diffuse cloud was observed in satellite data rising briefly above the cloud deck, though it was unclear if it was related to eruptive activity. Tremor ended after the event, and seismicity returned to low levels. Small explosions were detected by the seismic network at 2110 and 2246 on 26 October and 0057 and 0603 on 27 October. No ash clouds were identified in satellite data, but the volcano was obscured by high meteorological clouds. Additional small explosions were detected in seismic and infrasound data during 28-29 October; no ash clouds were observed in partly-cloudy-to-cloudy satellite images.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Sheveluch was identified in satellite data on 20, 22, and 25 October; weather clouds prevented views on the other days during 19-26 October. Moderate levels of gas-and-steam emissions rose from the volcano. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Turrialba | Costa Rica : OVSICORI-UNA reported that when weather conditions allowed for observations gas and periodic ash emissions rising from Turrialba were recorded by the webcam during 25-30 October. An event at 0134 on 26 October produced an ash plume that rose 500 m above the crater rim and drifted NE, causing ashfall in the neighborhoods of Coronado (San José, 35 km WSW) and San Isidro de Heredia (Heredia, 38 km W). Events at 0231 on 29 October and 1406 on 30 October produced plumes that rose 500 m and drifted NW and W respectively.

Veniaminof | United States : AVO reported that the eruption from the cone in Veniaminof’s ice-filled summit caldera, continued during 24-30 October. Satellite data showed elevated surface temperatures from minor lava fountaining and flows. Low-amplitude continuous tremor was detected. The webcam in Perryville, 35 km SE, periodically recorded diffuse ash emissions that often rapidly dissipated; minor ashfall was recorded in Perryville on 25 October. Based on satellite data acquired on 25 October the lava flows had traveled as far as 1.2 km from the vent, and the area of the flow field had doubled in the past month. Fractures in the ice sheet adjacent to the lava flow continued to grow due to meltwater flowing beneath the ice sheet. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale) and the Volcano Alert Level remained at Watch (the second highest level on a four-level scale).

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 29 August -2 September 2018

Aira | Kyushu (Japan) : JMA reported that there were 14 events and 15 explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 27 August-3 September, with ash plumes rising as high as 2.8 km above the crater rim and material ejected as far as 1.3 km. Crater incandescence was occasionally visible at night. The sulfur dioxide emission rate was 1,500 tons/day on 27 August. The Alert Level remained at 3 (on a 5-level scale).

Ambae | Vanuatu : The Vanuatu Meteorology and Geo-hazards Department reported that at 2015 on 1 September explosions at Ambae’s Lake Voui generated ash plumes that rose 4-11 km above the crater rim. According to the Wellington VAAC the ash plumes were visible in satellite images rising as high as 10.7 km (35,000 ft) a.s.l. and drifting E; the ash quickly dissipated. Moderate ashfall was likely produced in areas NE and E. The Alert Level remained at 3 (on a scale of 0-5).

Dukono | Halmahera (Indonesia) : Based on satellite data, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 29 August-4 September ash plumes from Dukono rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted N, NE, and E.

Ebeko | Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 24-31 August that sent ash plumes to 3-6 km (17,100 ft) a.s.l. A thermal anomaly was visible in satellite data during 24-25 and 30 August. Ash plumes drifted about 135 km SE, S, and SW during 24-25 and 27-30 August, producing ashfall on 29 and 30 August. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Fuego | Guatemala : INSIVUMEH reported that heavy rain generated lahars during 29 August-1 September that descended Fuego’s El Jute (SE), Las Lajas (SE), Cenizas (SSW), Taniluyá (SW), Seca (W), Mineral, Honda, and Pantaleón (W) drainages. The lahars were hot, had a sulfur odor, and carried tree branches and blocks (2-3 m in diameter). On 1 September lahars disrupted roads between San Pedro Yepocapa (8 km NW) and Sangre de Cristo (8 km WSW), and from Finca Palo Verde and El Porvenir (8 km ENE). During 2-4 September explosions produced ash plumes that rose as high as 950 m above the crater rim and drifted 10-15 km W and SW. Avalanches of incandescent material were confined to the crater. Ashfall was reported in areas downwind including San Pedro Yepocapa, Sangre de Cristo, Panimaché I and II (8 km SW), Morelia (9 km SW), and Finca Palo Verde.

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that an ash plume from Karymsky was identified in satellite images drifting about 40 km S on 25 August. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Kilauea | Hawaiian Islands (USA) : HVO reported a break in visible lava activity at Kilauea’s Fissure 8 during 26-31 August. On 1 September incandescence at Fissure 8 was evident in the afternoon; spattering from a small area produced lava flows that slowly covered the 15 x 65 m crater floor by the evening. Lava continued to fill the Fissure 8 crater on 3 September. The Volcano Alert Level remained at Watch and the Aviation colour Code remained at Orange.

Mayon | Luzon (Philippines) : PHIVOLCS reported that at 0653 on 27 August a short-lived degassing event at Mayon produced a light-brown ash plume that rose 200 m above the summit rim and drifted NE. During 28 August-3 September white steam plumes rose as high as 1 km and drifted in multiple directions. Crater incandescence was visible nightly. The Alert Level remained at 2 (on a 0-5 scale) and PHIVOLCS reminded residents to stay away from the 6-km-radius Permanent Danger Zone and the 7-km Extended Danger Zone on the SSW and ENE flanks.

Reventador | Ecuador : During 29 August-3 September IG reported a high level of seismic activity at Reventador, including explosions, long-period earthquakes, harmonic tremor, and signals indicating emissions. Steam, gas, and ash plumes rose as high as 600 m above the crater rim and drifted NE, NW, and W. Crater incandescence was visible.

Rincon de la Vieja | Costa Rica : OVSICORI-UNA reported two distinct, two-minute-long eruptions at Rincón de la Vieja beginning at 0434 and 1305 on 31 August. Weather conditions prevented webcam views and estimates of plume heights.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosions at Sabancaya averaged 25 per day during 27 August-2 September. Hybrid earthquakes were infrequent and of low magnitude. Gas-and-ash plumes rose as high as 3 km above the crater rim and drifted 50 km SE, E, and NE. The MIROVA system detected six thermal anomalies, and on 2 September the sulfur dioxide gas flux was high at 3,970 tons/day. The report noted that the public should not approach the crater within a 12-km radius.

Sangay | Ecuador : Based on satellite images and wind model data, the Washington VAAC reported that during 28 August-3 September ash emissions from Sangay rose to 5.8-6.7 km (19,000-22,000 ft) a.s.l. and drifted over 45 km in multiple directions. A thermal anomaly was sometimes visible.

Santa Maria | Guatemala : INSIVUMEH reported that during 1-4 September weak explosions at Santa María’s Santiaguito lava-dome complex generated ash plumes that rose 600-700 m and drifted SW. Avalanches of material descended the SE flanks of the lava dome. Ashfall was reported to the south in Monte Claro.

Semeru | Eastern Java (Indonesia) : Based on analysis of satellite images and wind model data, the Darwin VAAC reported that on 4 September a discrete eruption at Semeru generated an ash plume that rose to an altitude of 4.3 km (14,000 ft) a.s.l. and drifted W.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch was identified in satellite data during 25 and 28-30 August; cloudy weather prevented views of the volcano on the other days during 24-31 August. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Sierra Negra | Isla Isabela (Ecuador) : IG reported that the eruption at Sierra Negra that began on 26 June was divided into two main phases. The first and most energetic phase lasted one day (26 June) and was characterized by the opening of five fissures and lava flows traveling as far as 7 km from the vents. Lava was only produced from fissure 4 during the 57-day-long second phase (27 June-23 August), with lava reaching the sea on 6 July and expanding the coastline. By 25 August the lava flows in total covered an area of 30.6 square kilometers. Activity continued to decline the last week of August with decreased seismicity, gas emission, and no surficial activity visible.

Turrialba | Costa Rica : OVSICORI-UNA reported that at 1340 on 30 August an event at Turrialba produced an ash plume that passively rose 200 m above the crater rim and drifted SW. Gas-and-ash emissions became continuous during 31 August-1 September, with plumes rising 200 m and drifting SW and W.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 8 August -14 August 2018

Agung | Bali (Indonesia) : According to the Darwin VAAC, a webcam recorded an ash emission from Agung rising to an altitude of 4.3 km (14,000 ft) a.s.l. and drifting W. The Alert Level remained at 3 (on a scale of 1-4) with the exclusion zone set at a 4-km radius.

Aira | Kyushu (Japan) : JMA reported that there were five events and three explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 6-13 August, with ash plumes rising as high as 1.6 km above the crater rim and material ejected as far as 900 m. Crater incandescence was sometimes visible at night. The Alert Level remained at 3 (on a 5-level scale).

Dukono | Halmahera (Indonesia) : Based on satellite data, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 8-14 August ash plumes from Dukono rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted N, NE, and E.

Ebeko | Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 3-10 August that sent ash plumes as high as 3.7 km (12,100 ft) a.s.l. An ash cloud identified in satellite data drifted about 65 km E during 7-8 August. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Fuego | Guatemala : INSIVUMEH reported that on 9 August heavy rain triggered lahars that traveled down the Seca drainage on Fuego’s W flank and the Mineral drainage, carrying tree trunks and blocks as large a 2 m in diameter. During 12-14 August weak-to-moderate explosions generated ash plumes that rose almost as high as 1 km above the summit and drifted W and SW. Incandescent material was ejected 150 m high, and avalanches of blocks descended the Cenizas (SSW), Las Lajas (SE), and Santa Teresa (W) drainages. Ashfall was reported in Santa Sofía (12 km SW), Morelia (9 km SW), Panimaché I (8 km SW), and finca Palo Verde.

Ibu | Halmahera (Indonesia) : PVMBG reported that at 0259 on 13 August an event at Ibu generated an ash plume that rose 600 m above the crater rim. The Alert Level remained at 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.

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was identified in satellite images on 4 August, and an ash cloud drifted 50 km SE on 7 August. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Kilauea | Hawaiian Islands (USA) : HVO reported that during 8-14 August activity at Kilauea was characterized by a slowly-circulating lava pond deep within the Fissure 8 vent (though the pond was crusted over by 14 August) and a billowing gas plume, and a few scattered ocean entries. The summit area was quiet except for occasional rockfalls into the crater. Fresh black sand from fragmented lava was transported SW by the ocean current, and accumulated in the Pohoiki harbor, creating a sandbar. The westernmost ocean entry was about 1 km NE of the harbor. Earthquake and deformation data indicated no magma movement or pressurization in the system.

Krakatau | Indonesia : PVMBG reported that during 8-13 August incandescence emanated from Anak Krakatau at night. According to the Darwin VAAC, satellite data showed an ash plume rising to an altitude of 1.2 km (4,000 ft) a.s.l. and drifting W on 11 August. The Alert Level remained at 2 (on a scale of 1-4); residents and visitors were warned not to approach the volcano within 1 km of the crater.

Pacaya | Guatemala : INSIVUMEH reported that during 12-14 August Strombolian explosions at Pacaya’s Mackenney Crater ejected material as high as 30 m above the crater rim. A 300-m-long lava flow originating from Mackenney Crater was visible on NW flank.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosions at Sabancaya averaged 23 per day during 6-12 August. Hybrid earthquakes were infrequent and low magnitude. Gas-and-ash plumes rose as high as 2.9 km above the crater rim and drifted 40 km SE, E, and NE. The MIROVA system detected five thermal anomalies, and on 9 August the sulfur dioxide gas flux was high at 2,700 tons/day. The report noted that the public should not approach the crater within a 12-km radius.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that satellite images showed a thermal anomaly over Sheveluch during 6-7 August. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Sierra Negra | Isla Isabela (Ecuador) : IG reported that the eruption at Sierra Negra continued during 7-14 August. Incandescence from active NNW lava flows was visible almost nightly. A steam-and-gas plume rose 1.8 km a.s.l. and drifted W on 7 August.

Suwanosejima | Ryukyu Islands (Japan) : JMA reported that during 3-10 August white plumes rose as high as 1 km above the rim of Suwanosejima’s Ontake Crater, and incandescence from the crater was visible at night. The Alert Level remained at 2 (on a 5-level scale).

Turrialba | Costa Rica : OVSICORI-UNA reported that pulsating, passive ash emissions rising from Turrialba and drifting W were visible during periods of clear weather on 10 August. The next day a strong sulfur odor was reported in parts of Heredia (38 km W) and San José (36 km WSW).

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 25 July – 31 July 2018

Agung | Bali (Indonesia) : According to PVMBG a ground-based observer reported that at 0041 on 25 July an event at Agung produced a dense ash-and-gas plume that rose 700 m and drifted E and SE. Seismic data recorded the event for two minutes and 15 seconds. At 1406 on 27 July an event lasting one minute and 32 seconds produced a dense ash-and-gas plume that rose 2 km and drifted W. The Alert Level remained at 3 (on a scale of 1-4) and the exclusion zone was stable at a 4-km radius.

Aira | Kyushu (Japan) : JMA reported that there were four events and 11 explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 23-30 July, with ash plumes rising as high as 2.5 km above the crater rim and material ejected as far as 1.3 km. Crater incandescence was sometimes visible at night. Sulfur dioxide emissions were 2,100 tons per day on 26 July. 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 29-30 July ash plumes from Bagana rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted SW. A thermal anomaly was visible on 29 July.

Cleveland | Chuginadak Island (USA) : AVO reported that unrest at Cleveland continued during 25-31 July, though nothing significant was detected in seismic or infrasound data. Meteorological cloud cover prevented views of the crater on most days, though steaming from the crater was visible in satellite and webcam views during 25-26 July. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Dukono | Halmahera (Indonesia) : Based on PVMBG observations and satellite data, the Darwin VAAC reported that during 25-31 July ash plumes from Dukono rose to altitudes of 1.8-3.4 km (6,000-11,000 ft) a.s.l. and drifted N, NE, E, and S.

Ebeko | Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 20-21 and 25-26 July that sent ash plumes as high as 4 km (13,100 ft) a.s.l. An ash plume drifting about 15 km E was identified in satellite images on 20 July. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Fuego | Guatemala : INSIVUMEH reported that during 29-30 July avalanches of material descended the Cenizas drainage on Fuego’s SSW flank. Hot lahars generated by heavy rains on 30 July descended the Taniluyá (SW), Las Lajas (SE), El Jute (SE), and Cenizas drainages, carrying blocks 2-3 m in diameter and smelling of sulfur.

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that an ash cloud from Karymsky was identified in satellite images drifting 100 km SE on 20 July, and thermal anomalies were visible on 25 and 27 July. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Kilauea | Hawaiian Islands (USA) : HVO reported that the eruption at Kilauea’s Lower East Rift Zone (LERZ) and within Halema`uma`u Crater continued during 18-24 July. Lava fountaining and spatter was concentrated at Fissure 8, feeding lava flows that continued to spread through Leilani Estates and Lanipuna Gardens subdivisions, and entered the ocean at Ahalanui.

Inward slumping of the crater rim and walls of Halema`uma`u continued, adjusting from the withdrawal of magma and subsidence of the summit area. Explosions from collapse events occurred about every other day (38.5 and 53.5 hours in between a few of the events). Sulfur dioxide emissions from the summit were very low.

Fountaining at Fissure 8 continued, producing Pele’s hair and other volcanic glass that fell within Leilani Estates. The fountains continued to feed the lava flow that traveled NE, and then SSE, W of Kapoho Crater; lava occasionally overflowed the channel, and on 28 July ignited nearby vegetation. Small plumes of laze (a corrosive steam plume mixed with hydrochloric acid and fine volcanic glass particles) were generated at several points along a broad 2-km-wide flow front at Ahalanui. The westernmost edge was less than 175 m NE of the boat ramp in Isaac Hale Park (by 30 July).

Kirishimayama | Kyushu (Japan) : JMA reported that during 23-30 July white fumarolic plumes rose 300-500 m above a vent on the S side of Iwo-yama (also called Ioyama, NW flank of Karakuni-dake), a stratovolcano of the Kirishimayama volcano group. A hot pool of water was visible on the S side, and muddy water flowed down the W side. The Alert Level remained at 3 (on a scale of 1-5).

Piton de la Fournaise | Reunion Island (France) : OVPF reported that inflation at Piton de la Fournaise resumed after 13 July, the end of the last eruption. A period if increased seismicity was detected on 26 July, with 32 volcano-tectonic events less than 2 km deep being recorded during 0400-1600; 23 of those events were detected during 1200-1300.

Popocatepetl | Mexico : CENAPRED reported that each day during 25-31 July there were 24-42 steam-and-gas emissions from Popocatépetl, and nightly crater incandescence. Explosions were detected almost every day: five on 26 July; nine on 27 July; one on 28 July; three on 30 July. A series of gas-and-ash emissions began at 0307 on 31 July and lasted for 215 minutes. Ejected incandescent tephra landed on the flanks. The gas-and-ash plumes rose 2 km above the crater rim and drifted WSW, causing ashfall in Tetela del Volcán, Yecapixtla, Tlalnepantla, and Totolapan (Morelos state), and in Amecameca, Acuautla, Ecatzingo, Ozumba, and Tepetlixpa (Mexico state). The Alert Level remained at Yellow, Phase Two.

Rinjani | Lombok Island (Indonesia) : PVMBG and BNPB reported that a M 6.4 earthquake was recorded at 0547 on 29 July, shaking the islands of Lombok, Bali, and Sumbawa, and causing significant damage to buildings (including collapses) and roads, ground cracks, multiple injuries, and the death of 17 people in Lombok. The hypocenter was 24 km deep, and 47 km NE of Mataram City. Aftershocks were numerous and as large as M 5.7. The earthquakes caused remobilization of ash deposits on Rinjani as well as landslides. There were 1,226 visitors to the Mount Rinjani National Park Area at the time, and, according to news articles, about 690 climbers were on the volcano and had to be rescued. One person in the national park died from rockfalls. The Alert Level remained at 2 (on a scale of 1-4); the public was warned not to approach the crater within a 1.5-km radius.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosions at Sabancaya averaged 19 per day during 23-29 July. Hybrid earthquakes were infrequent and low magnitude. Gas-and-ash plumes rose as high as 3 km above the crater rim and drifted 40 km SE and E. On 26 July the sulfur dioxide gas flux was high at 4,195 tons/day. The report noted that the public should not approach the crater within a 12-km radius.

Santa Maria | Guatemala : INSIVUMEH reported that during 28-30 July explosions at Santa María’s Santiaguito lava-dome complex generated white plumes that rose 600-800 m and drifted SW. Avalanches of material descended the NW, E, and SE flanks of the lava dome.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that satellite images showed a weak thermal anomaly over Sheveluch during 19 and 21-22 July. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Turrialba | Costa Rica : OVSICORI-UNA reported that during 23-31 July activity at Turrialba was characterized by sporadic, passive gas-and-ash emissions detected almost daily. The plumes rose no higher than 300 m above the vent rim, and drifted NW, W, and SW. Ashfall was reported in several neighborhoods in the Valle Central, including Coronado, Tibás (35 km WSW), Goicoechea (28 km WSW), and Moravia (31 km WSW) on 24 July, and in Tres Ríos (27 km SW) on 31 July. A sulfur odor was occasionally reported.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 4 July – 10 July 2018

Aira | Kyushu (Japan) : JMA reported that there were two events and three explosions at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 2-9 July, with ash plumes rising as high as 1.3 km above the crater rim and material ejected as far as 1.1 km. Crater incandescence was sometimes visible at night. The Alert Level remained at 3 (on a 5-level scale).

Cleveland | Chuginadak Island (USA) : AVO reported that unrest at Cleveland continued during 4-10 July, though nothing significant was detected in seismic or infrasound data. Meteorological cloud cover often prevented views of the crater. Weakly elevated surface temperatures were identified in satellite images during 7 and 9-10 July; a small steam cloud was visible on 7 July. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Dukono | Halmahera (Indonesia) : Based on PVMBG observations and satellite data, the Darwin VAAC reported that during 4-10 July ash plumes from Dukono rose to altitudes of 1.5-2.1 km (5,000-7,000 ft) a.s.l. and drifted N, NE, and E.

Ebeko | Paramushir Island (Russia) : Volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, observed explosions during 30 June-1 July that sent ash plumes as high as 3.2 km (10,500 ft) a.s.l. Satellite data showed ash plumes drifting 57 km SE on 1 July. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Fuego | Guatemala : INSIVUMEH and CONRED reported relatively quiet conditions at Fuego during 4-9 July characterized mainly by gas emissions and block avalanches on the flanks. During 7-8 July there was about one explosion detected every two hours, producing diffuse ash plumes that rose 500 m above the crater and drifted SW. Block avalanches descended the Seca (W), Cenizas (SSW), and Las Lajas (SE) drainages, while lahars were present in the El Jute (SE), Las Lajas, Cenizas, Taniluyá (SW), Seca, Mineral, and Pantaleón (W) drainages. Seismicity increased on 10 July. Explosions generated ash plumes that rose 2.3 km and drifted 12 km SE, causing ashfall in Morelia (9 km SW) and Panimaché (8 km SW). According to CONRED, as of 4 July, the number of people confirmed to have died due to the 3 June pyroclastic flows was 113, and 332 remained missing.

Kilauea | Hawaiian Islands (USA) : HVO reported that the eruption at Kilauea’s Lower East Rift Zone (LERZ) and at Overlook Crater within Halema`uma`u Crater continued during 4-10 July. Lava fountaining and spatter was concentrated at Fissure 8, feeding lava flows that spread through Leilani Estates and Lanipuna Gardens subdivisions, and built out the coastline at multiple ocean entries. Fissure 22 produced spattering 50-80 m above its spatter cone and fed short lava flows that traveled NE on 4 July; weak spattering was visible form the cone the rest of the week.

Inward slumping of the crater rim and walls of Halema`uma`u continued, adjusting from the withdrawal of magma and subsidence of the summit area. Explosions from collapse events occurred almost daily, producing gas-and-ash-poor plumes.

Fountaining at Fissure 8 continued; lava fountains rarely rose higher than the 55-m-high spatter cone. Pele’s hair and other volcanic glass from the fountaining fell within Leilani Estates. The fountains continued to feed the lava flow that traveled NE, and then SE around Kapoho Crater. Occasional overflows sent small flows down the sides of the channel that did not extend beyond areas previously covered in lava in the upper part of the channel; overflows further down traveled beyond the flow-field boundary. Small brush fires were ignited from some of the overflows. A thermal map from 6 July showed that lava was not entering the ocean from the main channel and that the open channel ended about 2 km inland. Lava was flowing into the ocean at the N part of the broad flow front. Observations on 9 July indicated that a blockage had formed upstream of Kapoho Crater, and by 10 July a small lobe was moving around the W side of the crater.

Pacaya | Guatemala : INSIVUMEH reported that during 5-10 July Strombolian explosions at Pacaya’s Mackenney Crater ejected material as high as 30 m above the crater rim. White gas plumes drifted SW. A lava flow originating from Mackenney Crater traveled 500 m down the N flank during 7-8 July, reaching the volcano’s base.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosions at Sabancaya averaged 22 per day during 2-8 July. Hybrid earthquakes were infrequent and low magnitude. Gas-and-ash plumes rose as high as 2.5 km above the crater rim and drifted 30 km S, SE, and E. The MIROVA system detected nine thermal anomalies, and on 3 July the sulfur dioxide gas flux was high at 4,715 tons/day. The report noted that the public should not approach the crater within a 12-km radius.

Santa Maria | Guatemala : INSIVUMEH reported that during 5-10 July explosions at Santa María’s Santiaguito lava-dome complex generated ash plumes that rose 200-700 m and drifted SW and W. Local ashfall was reported. Avalanches of material descended the SE and W flanks of the lava dome.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Sheveluch was identified in satellite images during 4-5 July. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week of 27 June – 3 July 2018

Agung | Bali (Indonesia) : PVMBG reported that seismicity at Agung continued to be dominated by low-frequency events. The number of earthquakes increased from 15/day on 25 June to 69/day on 28 June; harmonic tremor emerged on 27 June, and at 2221 an event generated an ash plume that rose 2 km above the crater rim and drifted W. Gas-and-ash emissions were continuous during 28-29 June, rising around 2 km and drifting W and SW, and incandescence was reflected in the plume; satellite data confirmed that high-temperature (1,200 degrees Celsius) lava flowed onto the crater floor. The intensity of the thermal anomaly on 29 June was the largest recorded at Agung since the beginning of the eruption on 21 November 2017.

BNPB noted that the ash plumes on 28 June caused some airlines to cancel flights to Bali, and ashfall was reported in several villages on Bangli. The International Gusti Ngurah Rai (IGNR) airport (60 km SW) in Denpasar, the Blimbing Sari Airport (128 km W) in Banyuwangi, and the Noto Hadinegoro Airport (200 km W) in Jember closed for portions of the day on 29 June.

Lava continued to effuse, and by 1 July the estimated volume of new lava was 4-5 million cubic meters making the total volume erupted since 21 November 2017 around 27-28 million cubic meters (50% of the total crater volume). The height difference between the lowest part of the crater rim (SW side) and the highest part of the lava surface (in the center of the crater) was 85-90 m. Satellite data showed that the intensity of the thermal anomaly decreased during 28 June-2 July, though still remained at a high level. At 2104 on 2 July an explosion generated an ash plume that rose 7-9 km above the crater rim, and ejected incandescent lava as far as 2 km onto the flanks. News articles noted that the deposits caused forest fires on the upper flanks, and that the event prompted about 700 people to evacuate. An event at 0413 on 3 July generated an ash plume that rose around 2 km. The Alert Level remained at 3 (on a scale of 1-4) and the exclusion zone was stable at a 4-km radius.

Great Sitkin | Andreanof Islands (USA) : AVO reported that after the brief explosion at Great Sitkin on 10 June seismicity gradually declined to background levels. On 27 June AVO lowered the Volcano Alert Level to Normal and the Aviation colour Code to Green.

Ibu | Halmahera (Indonesia) : Based on satellite images and model data, the Darwin VAAC reported that on 27 June an ash plume from Ibu rose to 1.8 km (6,000 ft) a.s.l. and drifted W. The Alert Level remained at 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.

Krakatau | Indonesia : PVMBG reported that white plumes were seen rising as high as 100 m above Anak Krakatau during infrequent periods of clear weather from 27 June to 3 July. Incandescence from the summit was observed at night during 1-2 July. The Alert Level remained at 2 (on a scale of 1-4); residents and visitors were warned not to approach the volcano within 1 km of the crater.

Sierra Negra | Isla Isabela (Ecuador) : Based on video and photos shared by Parque Nacional Galápagos staff, IG reported that the eruption at Sierra Negra that began at 1340 on 26 June originated from several fissures on the N flank and one within the caldera. The flank flows reached the sea between Elizabeth Bay and Punta Morena. A gas-and-ash plume rose about 10.5 km and drifted W. Seismic and acoustic data indicated a gradual decrease but continuing activity on 27 June. A small seismic event was recorded at 1552 on 1 July, followed by at least four hours of tremor. At 1600 national park staff observed lava flows on the NW flank.

Yasur | Vanuatu : The Vanuatu Meteorology and Geo-hazards Department reported some stronger explosions at Yasur during 27-28 June. Based on webcam images the Wellington VAAC reported that on 29 June intermittent, low-level ash plumes rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted NW. The Alert Level remained at 2 (on a scale of 0-4). VGO reminded residents and tourists that hazardous areas were near and around the volcanic crater, within a 395-m-radius permanent exclusion zone, and that volcanic ash and gas could reach areas impacted by trade winds.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 20 June – 26 June 2018

Aira | Kyushu (Japan) : JMA reported that there were four events and one explosion at Minamidake crater (at Aira Caldera’s Sakurajima volcano) during 18-25 June, with ash plumes rising as high as 1.9 km above the crater rim. Crater incandescence was visible at night on 18 June. The Alert Level remained at 3 (on a 5-level scale).

Cleveland | Chuginadak Island (USA) : AVO reported that a satellite image of Cleveland acquired on 25 June showed a small, circular lava flow about 80 m in diameter in the summit crater. The presence of a flow over the active vent increases the chances of an explosion, so AVO raised the Aviation colour Code to Orange and the Volcano Alert Level to Watch.

Copahue | Central Chile-Argentina border : The Buenos Aires VAAC reported that on 24 June diffuse steam emissions with possible ash were visible in webcam views rising to an altitude of 3.6 km (12,000 ft) a.s.l.

Dukono | Halmahera (Indonesia) : Based on PVMBG observations and satellite data, the Darwin VAAC reported that during 20-26 June ash plumes from Dukono rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted NW, W, and SW.

Ebeko | Paramushir Island (Russia) : KVERT reported that on 15 June an ash plume from Ebeko was visible in satellite images drifting 14 km SE. Video data from SVERT and KBGS RAS (Kamchatka Branch, Geophysical Service, Russian Academy of Sciences) showed ash explosions during 17-18 June that sent ash plumes to 2.5-3 km (8,200-10,000 ft) a.s.l. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Fuego | Guatemala : INSIVUMEH and CONRED reported that during 20-26 June multiple lahars at Fuego were often hot, steaming, and had a sulfur odor, and were generated from heavy rains and the recent accumulation of pyroclastic-flow deposits from the 3 June events. Lahars remained a significant hazard, and descended the Cenizas (SSW), Las Lajas (SE), Santa Teresa (W), and Taniluyá (SW) drainages. They were 25-45 m wide, as deep as 3 m, and often carried blocks up to 3 m in diameter, tree trunks, and branches. The agencies warned that because the Las Lajas drainage is full of deposits, lahars can continue to descend that drainage or create new channels in San Miguel Los Lotes (one of the hardest-hit areas).

Explosions continued, producing ash plumes that rose as high as 1.3 km above the crater and drifted as far as 15 km in multiple directions. Ashfall was reported in Panimache, Morelia, Sangre de Cristo, and finca Palo Verde on 22 June. Avalanches of material descended the SE, S, and W flanks (Santa Teresa, Las Lajas, and Cenizas drainages). According to CONRED, as of 26 June, the number of people confirmed to have died due to the 3 June pyroclastic flows was 112, and 197 more were missing. In addition, 12,823 remained evacuated.

Kilauea | Hawaiian Islands (USA) : HVO reported that the eruption at Kilauea’s Lower East Rift Zone (LERZ) and at Halema`uma`u Crater continued during 20-26 June. Lava fountaining and spatter was concentrated at Fissure 8, feeding lava flows that spread through Leilani Estates and Lanipuna Gardens subdivisions, and built out the coastline where the fast-moving flow entered the ocean in the area of the former Kapoho Bay. Fissure 16/18 was often incandescent, and lava effusion was visible at Fissure 6 on 21 June. Fissure 22 produced weak lava fountains on 22 June, and weak spattering and small lava flows on 26 June.

Inward slumping of the crater rim and walls of Halema`uma`u continued, adjusting from the withdrawal of magma and subsidence of the summit area. Steam plumes rose from areas in the crater as well as from circumferential cracks adjacent to the crater. Explosions from collapse events occurred daily, producing gas-and-ash-poor plumes that rose less than 1.8 km (6,000 ft) a.s.l. and drifted SW. On 24 June HVO noted that since late May these plumes rarely rose higher than 3 km (10,000 ft) a.s.l. where they can cause an aviation hazard; the Aviation colour Code was reduced to Orange.

Fountaining at Fissure 8 continued; lava fountains rose occasionally higher than the 55-m-high spatter cone. Pele’s hair and other volcanic glass from the fountaining fell within Leilani Estates. The fountains continued to feed the fast-moving lava flow that traveled NE, and then SE around Kapoho Crater, and into the ocean. Occasional overflows sent small flows down the sides of the channel. The lava-flow front at the ocean was almost 3.2 km wide by 25 June, with lava entering the ocean on the S side of the flow front mainly through an open channel, but also along a 1-km-long area marked with billowing laze plumes.

Kirishimayama | Kyushu (Japan) : JMA reported that at Shinmoedake (Shinmoe peak), a stratovolcano of the Kirishimayama volcano group, an explosive eruption at 0909 on 22 June generated an ash plume that rose 2.6 km above the crater rim and drifted E. Tephra was ejected 1.1 km away, and shock waves were felt in the Miyazaki region. Minor amounts of ash fell in Kirishima prefecture and Kagoshima prefecture to the S, Miyakonojo city (Miyazaki prefecture) to the E, and Takahara Town. The Alert Level remained at 3 (on a scale of 1-5).

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images during 16-17 and 19 June. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Langila | New Britain (Papua New Guinea) : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that during 20-21 June ash plumes from Langila rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted W and NW.

Mauna Loa | Hawaiian Islands (USA) : On 21 June HVO reported that seismicity and deformation at Mauna Loa had been at near-background levels for at least the previous six months. The Aviation colour Code was lowered to Green and the Volcano Alert Level was lowered to Normal. During 2014 through most of 2017 seismicity was variable but elevated, and ground deformation was consistent with an influx of magma in the shallow reservoir.

Nishinoshima | Japan : JMA reported that seismic, thermal, RADAR, and sulfur dioxide data all showed no eruptive activity at Nishinoshima since mid-August 2017. During an overflight on 14 June the Japan Coast Guard noted white fumarolic plumes rising about 20 m from the E side of main cone’s inner wall and from the center of the crater. Ocean water all around the island was discoloured, especially in the N-to-NW quadrant where the yellowish brown water extended 200-300 m from the shore. On 20 June the JMA reduced the warning level for the island, specifying hazards were less severe “around the crater” (encompassing areas within 500 m).

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosions at Sabancaya averaged 29 per day during 18-24 June. Hybrid earthquakes were infrequent and low magnitude. Gas-and-ash plumes rose as high as 1.8 km above the crater rim and drifted 30 km S, SE, and E. The MIROVA system detected 11 thermal anomalies, and on 21 June the sulfur dioxide gas flux was high at 4,900 tons/day. The report noted that the public should not approach the crater within a 12-km radius.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Sheveluch was identified in satellite images during 16-17 and 19 June. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Sinabung | Indonesia : Based on observations by PVMBG, satellite and webcam images, and model data, the Darwin VAAC reported that during 20-22 June ash plumes from Sinabung rose 3-3.7 km (10,000-12,000 ft) a.s.l. and drifted SE and E. 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.

Yasur | Vanuatu : Based on webcam images and local visual observations the Wellington VAAC reported that during 20-21 June intermittent, low-level ash plumes from Yasur rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted SE.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week of 14 March – 20 March 2018

Ambae | Vanuatu : On 18 March the Vanuatu Geohazards Observatory (VGO) reported that eruptive activity at Ambae’s Lake Voui during February-March was similar to activity observed at the end of October 2017, but with more sustained ash emissions from explosions at the vent. The ongoing ash-and-gas emissions were impacting local villages, prompting VGO to raise the Alert Level to 3 (on a scale of 0-5) and to warn residents and tourists to stay outside of the Danger Zone defined as a 3-km radius around the active vent in Lake Voui. A news article noted that ashfall was reported in the NW, W, SW, and S parts of the island.

Kick ’em Jenny | North of Grenada : The University of the West Indies (UWI) Seismic Research Centre (SRC) and the National Disaster Management Agency (NaDMA) reported that during 12-15 March seismicity at Kick ’em Jenny significantly decreased. The Alert Level remained at Orange (the second highest level on a four-colour scale) with a 5-km maritime exclusion zone.

Kikai | Japan : JMA reported that one small-amplitude, short-duration volcanic tremor was detected on 16 March at Satsuma Iwo-jima, a subaerial part of Kikai’s NW caldera rim. The number of volcanic earthquakes increased on 19 March, prompting JMA to raise the Alert Level to 2 (on a 5-level scale), and then decreased the next day. The report noted increased thermal activity since February, with occasional visual observations of incandescence.

Kirishimayama | Kyushu (Japan) : JMA reported that the eruption at Shinmoedake (Shinmoe peak), a stratovolcano of the Kirishimayama volcano group, continued during 13-19 March. Lava effusion possibly stopped on 9 March, though the lava flow on the NW flank continued to advance. An explosion at 1413 on 15 March generated a gray-white plume that rose 2.1 km above the crater and ejected material 1 km from the crater. A high number of volcanic earthquakes continued to be recorded, in addition to many low-frequency earthquakes with shallow hypocenters. Volcanic tremor was occasionally recorded. The Alert Level remained at 3 (on a scale of 1-5).

Stromboli | Aeolian Islands (Italy) : INGV reported that during 12-17 March activity at Stromboli was at normal levels, characterized by explosive activity and gas emissions from two vents (N1 and N2) in Area N and two vents in Area C-S (C and S2). Explosions at N1 ejected lapilli, bombs, and sometimes ash less than 120 m high, and less intense explosions at N2 emitted ash no higher than 80 m. The frequency of explosions in Area N was 3-8 events/hour. Continuous gas emissions rose from C. Explosions at S2 emitted ash no higher than 80 m at a rate of 2-5 explosions/hour. A high-energy explosive sequence began at vent C at 2027 on 19 March and lasted about 40 seconds. The first explosion ejected ash and incandescent material that fell in a radial distribution around the crater. Two subsequent explosions ejected incandescent material as high as 80 m. Tephra fell along the Sciara del Fuoco, towards the NE parts of the island. At 2028 an explosion at N2 ejected lapilli 100-120 m high.

Volcanos

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

Kadovar | Papua New Guinea : RVO reported that the eruption at Kadovar continued during 18-19 and 21-22 January. Main Crater produced ash plumes that rose as high as 800 m above the summit and drifted tens of kilometers E, SE, S, and SW. Vulcanian activity was continuous, though no discrete explosions were detected. Steam plumes from the SE Coastal Vent rose 800 m above the island, and a lava dome which strongly and continuously glowed at night slowly extruded from the vent. Strong sulfur dioxide emissions were detected.

Kusatsu-Shiranesan | Honshu (Japan) : JMA reported that at 0959 on 23 January an eruption began at Kusatsu-Shiranesan coincident with the onset of volcanic tremor; there were no indications of an impending eruption. The Alert Level was raised to 3 (on a scale of 1-5). Skiers at the popular ski resort Kusatsu Kokusai took video showing a plume of tephra and ejected bombs rising from a vent on the Motoshiranesan edifice, about 2 km SSE of Yagama Crater on Shiranesan (where all previous historical activity has been). The eruption also caused what appeared to be an avalanche. Photos and video posted in news articles showed tephra drifting E and blanketing the nearby hillside; JMA noted ashfall in Nakanojo-machi, in the Gunma Prefecture. Tephra hit a gondola, shattering glass and injuring four skiers. Material crashed through the roof of a lodge, where about 100 people had already been evacuated. Ground Self-Defense Force troops were engaging in ski training at the time of the event; one member died and seven others were injured. Emergency responders gathered at the Sanroku Station to assist. On 24 January JMA noted that volcanic earthquakes were numerous but decreasing in number, and two 2-3-minute-long periods of volcanic tremor were detected at 1015 and 1049.

Mayon | Luzon (Philippines) : PHIVOLCS reported that during 16-17 January Mayon’s seismic network recorded 143 lava collapse events associated with rockfalls along the front and margins of advancing lava and pyroclastic flows in the Miisi (S), Matanag (SE), and Buyuan (SE) drainages. These events generated ash plumes that drifted SW. During 17-20 January effusion of lava at the summit and collapse events continued. Two pyroclastic flows traveled around 3 km down the Miisi drainage. Rockfall events were generated by the collapsing lava front and margins of the advancing 3-km-long lava flow in the Miisi drainage, and from the summit into the Matanag, Buyuan, and Bonga (SE) drainages. Ash plumes continued to drift SW. Sulfur dioxide gas emissions were 1,478 tonnes/day on 18 January and 1,131 tonnes/day on 19 January. During 20-21 January there were 14 rockfall events and 10 pyroclastic flows recorded by the seismic network.

During 21-22 January there were 64 rockfall events and one pyroclastic flow recorded. Strombolian activity generated lava fountains 500 and 200 m high at 1045 on 21 January and at 0225 on 22 January, respectively. Ash plumes rose 1.3 km high and drifted SW, causing ashfall in Oas and Guinobatan (12 km SW). Lava flowed more voluminously, adding to the advancing Miisi lava flow (over 3 km long) and feeding two new lava flows on the Bonga and upper Buyuan drainages.

At 1243 on 22 January an eight-minute-long phreatomagmatic event generated a dense, 5-km-high ash plume that drifted W. Ashfall was reported in the municipalities of Guinobatan, Camalig (11 km SSW), Oas, Polangui (20 km WNW), and Iriga City (34 km NW). The event also generated pyroclastic flows that traveled as far as 4 km down multiple drainages including Miisi, Bonga, Buyuan, Basud, San Andres, Buang, Anoling. PHIVOLCS raised the Alert Level to 4 (on a 0-5 scale) and extend the Danger Zone to an 8-km radius. A minor event at 1725 produced a 500-m-high ash plume. Between 2137 on 22 January and 0525 on 23 January there were five episodes of intense and sporadic lava fountaining, each lasting 3-30 minutes. The lava fountains rose 500-700 m high, and generated ash plumes that rose 2.5-3 km above the crater. The events fed lava flows on the Miisi and Bonga drainages, sprayed near-vent lava spatter, and fed incandescent rockfalls around the summit area. The Buyuan lava flow was 200 m long. According to news articles posted on 23 January about 40,000 people have been evacuated, and airports in the cities of Legazpi City (13 km SSE) and Naga (66 km NW), and on the nearby island of Masbate (100 km S) were closed.

Nevados de Chillan | Chile : Servicio Nacional de Geología and Minería (SERNAGEOMIN) Observatorio Volcanológico de Los Andes del Sur (OVDAS) reported continuing explosive activity during 1-15 January associated with a low rate of lava-dome growth in the active crater. Gas plumes from the explosions rose less than 1 km above the crater rim, and sporadic incandescence associated with some explosions was recorded at night. The lava-dome growth rate was low at 1,360 m3/day, determined by photos taken during overflights on 9 and 12 January. The total volume of the lava dome was an estimated 37,000 m3. 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 during 14-17 January there were four gas-and-ash emissions from San Miguel that rose no higher than 300 m above the crater rim. The report noted that prior to each emission seismicity decreased and then suddenly increased.