Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 12 July – 18 July 2017

Bagana | Bougainville (Papua New Guinea) : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that on 16 July an ash plume from Bagana drifted W at an altitude of 2.1 km (7,000 ft) a.s.l.

Bezymianny | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly was identified over Bezymianny daily in satellite images. A lava flow continued to flow down the W flank of the dome. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Cleveland | Chuginadak Island (USA) : AVO reported that during 12-18 July no significant activity at Cleveland was observed in cloudy or mostly cloudy satellite and web camera images; some minor steaming was noted. Moderately elevated surface temperatures were identified in satellite images on 14 July. Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Copahue | Central Chile-Argentina border : Based on webcam and satellite images the Buenos Aires VAAC reported that during 16-17 July steam-and-ash plumes rose from Copahue to altitudes of 3-3.4 km (10,000-11,000 ft) a.s.l. and drifted N and NW.

Dukono | Halmahera (Indonesia) : Based on analyses of satellite imagery, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 12-15 July ash plumes from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted W, NW, and S. Ash plumes on 17 July rose 1.5 km (5,000 ft) a.s.l. and drifted E.

Ebeko | Paramushir Island (Russia) : Based on observations by residents of Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, explosions during 7-8 July 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).

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Karymsky was identified in satellite images during 7 and 11-12 July. Ash plumes drifted 170 km SW and SE on 10 and 11 July, respectively. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Kilauea | Hawaiian Islands (USA) : During 12-18 July 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, from a vent high on the NE flank of the cone, and from a small lava pond (which had many small spattering sites along the margin) in a pit on the W side of the crater. The 61G lava flow, originating from a vent on Pu’u ‘O’o Crater’s E flank, continued to enter the ocean at Kamokuna. Several large cracks running parallel to the coastline spanned the width of the delta; several small collapses at the leading edge of the delta were noted on 11 July. Surface lava flows were active above and on the pali, and on the coastal plain within 1 km of the base of the pali.

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that during 8 and 12-13 July explosions at Klyuchevskoy generated ash plumes that rose as high as 5 km (16,400 ft) a.s.l. and drifted about 50 km SE. A weak thermal anomaly was identified in satellite images during 10-12 July. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Poas | Costa Rica : OVSICORI-UNA reported that during 12-17July gas plumes that rose as high as 1 km above Poás’s vents A (Boca Roja) and B (Boca Azufrada) drifted SW and NW.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya increased compared to the previous week; there was an average of 19 explosions recorded per day during 10-16 July. Gas-and-ash plumes rose 3.5 km above the crater rim and drifted more than 40 km NW and E. Sulfur dioxide flux was as high as 2,959 tons per day, recorded on 16 July. The MIROVA system detected six thermal anomalies. An explosion at 0931 on 19 July generated an ash plume that rose 4 km above the crater rim and drifted N.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly was identified daily in satellite images over Sheveluch during 7-11 July; cloud cover prevented views during 12-14 July. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Sinabung | Indonesia : Based on PVMBG observations, satellite and webcam images, and wind data, the Darwin VAAC reported that during 14-15 July ash plumes from Sinabung rose 3.3-4.9 km (11,000-16,000 ft) a.s.l. and drifted E, ESE, SE, and W.

Turrialba | Costa Rica : OVSICORI-UNA reported eruptive events at Turrialba daily during 12-17 July. Gas and ash plumes rose 200-500 m above the vent and generally drifted NW, W, and SW. There were multiple events on 15 July, causing ashfall in Sabanilla de Montes de Oca (30 km WSW), Ipis (27 km SW), El Carmen de Guadalupe, Purral (26 km WSW), Guadalupe (32 km WSW), and Tibás (35 km WSW). A sulfur dioxide odor was also reported that day, in San José (36 km WSW), Tibas (35 km WSW), Guadalupe, Escazú (42 km WSW), and Puriscal (65 km WSW).

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week of 12 July – 18 July 2017

Bogoslof | Fox Islands (USA) : AVO reported that during 12-18 July no significant activity at Bogoslof was observed in cloudy or mostly cloudy satellite images; weakly elevated surface temperatures were noted on 12 and 16 July. In addition no activity was detected in seismic, infrasound, or lightning data. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Fuego | Guatemala : INSIVUMEH reported that multiple explosions at Fuego during 13-14 July generated ash plumes that rose as high as 950 m above the crater and drifted 8-10 km NW and W. Incandescent material was ejected 100 m above the crater rim, and caused avalanches of material that traveled down the Ceniza (SSW), Taniluyá (SW), and Trinidad (S) drainages. On 16 July a 30-m-wide, 2-m-deep, hot lahar descended tributaries of the Pantaleón (W) drainage, carrying blocks more than 2 m in diameter, branches, and tree trunks. The lahars again overtook the road between communities on the SW flank, isolating the village of Sangre de Cristo (8 km WSW) and the Palo Verde estate. Vulcanian explosions during 17-18 July produced dense ash plumes that rose almost 1 km above the crater rim and drifted 15 km W and NW. Ash fell in Panimache (8 km SW), Morelia (9 km SW), and Santa Sofía (12 km SW).

Sangeang Api | Indonesia : PVMBG reported a small eruption at Sangeang Api at 1154 on 15 July characterized by Strombolian activity, and an ash plume that rose 100-200 m above the crater rim and drifted SW. Prior to the event, thermal anomalies had increased beginning in March, and seismicity had increased starting in April. Based on analyses of satellite imagery, PVMBG observations, and wind data, the Darwin VAAC reported that on 16 July an ash plume rose to an altitude of 2.1 km (7,000 ft) a.s.l., or 200 m above the crater rim, and drifted NW.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 5 July – 11 July 2017

Aira | Kyushu (Japan) : JMA reported a very small eruption at Showa Crater (at Aira Caldera’s Sakurajima volcano) on 3 July. The Alert Level remained at 3 (on a 5-level scale).

Bezymianny | Central Kamchatka (Russia) : KVERT reported that incandescence from Bezymianny’s lava dome was observed at night during 1-7 July, and a lava flow continued to flow down the W flank of the dome. A thermal anomaly was identified daily in satellite images. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Cleveland | Chuginadak Island (USA) : AVO reported that during 5-11 July no significant activity at Cleveland was observed in cloudy or mostly cloudy satellite and web camera images; some minor degassing was noted. Seismicity remained low. The Aviation Color Code remained at Orange and the Volcano Alert Level remained at Watch.

Copahue | Central Chile-Argentina border : Based on webcam and satellite images the Buenos Aires VAAC reported that during 7-8 July steam plumes with minor amounts of ash rose from Copahue to altitudes of 4-4.3 km (13,000-14,000 ft) a.s.l. and drifted ESE.

Dukono | Halmahera (Indonesia) : Based on analyses of satellite imagery, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 5-11 July 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 residents of Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, explosions on 1 and 4 July generated ash plumes that rose as high as 2.6 km (8,500 ft) a.s.l. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was identified in satellite images during 1-3 July. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Kilauea | Hawaiian Islands (USA) : During 5-11 July 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, from a vent high on the NE flank of the cone, and from a small lava pond (which had many small spattering sites along the margin) in a pit on the W side of the crater. The 61G lava flow, originating from a vent on Pu’u ‘O’o Crater’s E flank, continued to enter the ocean at Kamokuna. Several large cracks running parallel to the coastline spanned the width of the delta. Surface lava flows were active above and on the pali, and on the coastal plain.

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that during 1-2 and 5-6 July a weak thermal anomaly was identified in satellite images at Klyuchevskoy. Explosions during 1-2 and 5-6 July generated ash plumes that rose as high as 5 km (16,400 ft) a.s.l. and drifted 160 km SE, S, and SW. The Aviation Color Code remained at Orange (the second highest level on a four-color scale).

Nishinoshima | Japan : Based on satellite images and pilot observations the Tokyo VAAC reported that on 5 July an ash plume from Nishinoshima drifted E.

Poas | Costa Rica : OVSICORI-UNA reported that during 4-9 July plumes of magmatic gases, water vapor, and aerosols rose 200-600 m above Poás’s vents A (Boca Roja) and B (Boca Azufrada). Minor incandescence from the bottom of the crater was observed during 4-5 July, and a strong sulfur odor was reported in some areas of Alajuela and Heredia. During 5-7 July grayish-red ash emissions rose intermittently from vent A, and on 7 July a loud “jet” sound was noted in Mirador. A strong sulfur odor and minor ashfall was reported in some areas of Alajuela. An event at 1450 on 10 July generated a plume that rose 300 m.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya increased compared to the previous week; there was an average of 10 explosions recorded per day during 3-9 July, and the explosions were more energetic. Gas-and-ash plumes rose 5.5 km above the crater rim and drifted more than 50 km NW and S. Sulfur dioxide flux was as high as 2,239 tons per day.

Santa Maria | Guatemala : INSIVUMEH reported that on 5 July a moderate lahar descended the Cabello de Ángel drainage, a tributary of the Nimá I river. Near the El Faro estate, the lahar was 30 m wide and 1 m deep, and carried blocks 50 cm in diameter. Weak explosions on 7 July generated white plumes that rose 700 m and drifted 2 km SE; minor ashfall was reported in the ranches of La Florida (5 km S) and Monte Claro (S). Weak avalanches of material traveled short distances down the E flank. Explosions during 10-11 July generated ash plumes that rose 600 m and drifted SW, causing some ashfall in La Florida.

Sinabung | Indonesia : Based on PVMBG observations, satellite images, and wind data, the Darwin VAAC reported that during 6 and 8-11 July ash plumes from Sinabung rose 3.3-5.5 km (11,000-18,000 ft) a.s.l. and drifted E, ESE, SE, and NW.

Turrialba | Costa Rica : OVSICORI-UNA reported that during 4-11 July plumes of water vapor, aerosols, and magmatic gases rose as high as 500 m above Turrialba’s crater rim, and on most nights incandescence emanated from Cráter Oeste. The emissions sporadically contained moderate amounts of ash during 5-7 July. Minor ashfall was reported in Coronado (San José), and in San Rafael and Barva (Heredia). Parque Nacional Volcán Turrialba staff reported that ash was deposited in the region between La Silvia and La Picada farms. Events at 1325 on 10 July and 1545 on 11 July generated plumes that rose 300 and 500 m above the crater rim, respectively.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week of 5 July – 11 July 2017

Bogoslof | Fox Islands (USA) : On 5 July AVO reported that no further activity was detected at Bogoslof after the explosions the day before; the Aviation colour Code (ACC) was lowered to Orange and the Volcano Alert Level (VAL) was lowered to Watch. A nine-minute-long eruption pulse was detected in seismic data starting at 1015 on 8 July was followed by a shorter pulse that began at 1029 and then a decline in seismicity. An ash plume identified in satellite images rose 9.1 km (30,000 ft) a.s.l. and drifted N. AVO raised the ACC to Red and the VAL to Warning, but lowered them back down to Orange and Watch, respectively, the next day. An eruption began at 2347 on 9 July, lasted five minutes, and was followed 15 minutes later by another explosion that lasted seven minutes. A small ash cloud visible in satellite images drifting SE may have risen as high as 6.1 km (20,000 ft) a.s.l. Explosions ended at 0235 on 10 July. The ACC was raised to Red and the VAL was raised to Warning but lowered back down one level early on 10 July. An eruption began at 1000 on 10 July and lasted eight minutes. Infrasound data indicated ash emissions but ash was not confirmed in satellite data. A 15-minute-long event began at 1706 on 10 July; no volcanic plume was identified in satellite data, and no volcanic lightning nor infrasound was detected. Seismicity declined after the episode.

Fuego | Guatemala : INSIVUMEH reported that 4-7 explosions per hour at Fuego during 6-7 July generated ash plumes that rose as high as 950 m above the crater and drifted 6-10 km SW and W. Incandescent material was ejected 100-200 m above the crater rim, and caused avalanches of material that traveled down the Ceniza (SSW), Taniluyá (SW), Santa Teresa (SW), and Trinidad (S) drainages. Later on 7 July the rate of explosions increased to 7-10 per hour. During 7-9 July ash plumes rose as high as 1.1 km and drifted 15 km W, causing ashfall in 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), and possibly San Pedro Yepocapa (8 km N). A lava flow traveled 1.5 km down the Las Lajas (SE) drainage. On 11 July INSIVUMEH declared that the 6th eruption of the year with lava effusion was in progress. Explosions generated ash plumes that rose as high as 1.3 km above the crater and drifted 35 km W, and shock waves rattled nearby structures. Ash fell in areas including Morelia, Panimache, Santa Sofía, El Porvenir, and Sangre de Cristo. Two lava flows were fed by lava fountains 150-250 m high; one lava flow traveled 2.3 km down the Las Lajas drainage and another traveled 1.7 km down the Santa Teresa (SW) drainage. Later that day INSIVUMEH reported that the 31-hour-long eruption had ended. A few weak-to-moderate explosions continued, generating ash plumes that rose 850 m and drifted 6 km W.

Rincon de la Vieja | Costa Rica : OVSICORI-UNA reported that at 0849 on 5 July a small phreatic eruption at Rincón de la Vieja ejected material that fell within the crater.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly was identified daily in satellite images over Sheveluch during 1-7 July. Explosions on 2 July generated ash plumes that rose 10-11 km (32,800-36,100 ft) a.s.l.; one plume drifted 1,050 km SW and another drifted 350 km NE. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 28 June – 4 July 2017

Aira | Kyushu (Japan) : JMA reported that events at Showa Crater (at Aira Caldera’s Sakurajima volcano) at 1811 and 1904 on 27 June generated ash plumes that rose 1 km above the crater rim. Weak incandescence from the crater was noted on 30 June. During 30 June-3 July there were five events, one of which was explosive. Material was ejected as far away 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 on 2 July an ash plume from Bagana drifted W at an altitude of 2.1 km (7,000 ft) a.s.l.

Bezymianny | Central Kamchatka (Russia) : KVERT reported that incandescence from Bezymianny’s lava dome was observed at night during 23-30 June, and a lava flow continued to flow down the W flank of the dome. A thermal anomaly was identified daily in satellite images. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Cleveland | Chuginadak Island (USA) : A moderate 10-minute-long explosion at Cleveland was detected in both seismic and infrasound data beginning at 0319 on 4 July, prompting AVO to raise the Aviation colour Code to Orange and the Volcano Alert Level to Watch. After the event, seismicity declined and remained low. Satellite images showed no clear evidence of an ash plume.

Copahue | Central Chile-Argentina border : OVDAS-SERNAGEOMIN reported that during 5-15 June the seismic network at Copahue detected long-period earthquakes. Gas plumes constantly rose from El Agrio crater and on several days contained ash. The highest plume, detected on 5 June, rose 300 m and drifted E. The Buenos Aires VAAC reported that on 1 July the webcam recorded a steam-and-gas plume with minor ash near the summit. The Alert Level remained at Yellow (the second lowest on a four-colour scale); SERNAGEOMIN recommended no entry into a restricted area within 1 km of the crater.

Dukono | Halmahera (Indonesia) : Based on analyses of satellite imagery, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 28 June-4 July ash plumes from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted E, ESE, and S.

Ebeko | Paramushir Island (Russia) : Based on observations by residents of Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, explosions during 23-30 June generated ash plumes that rose as high as 2 km (6,600 ft) a.s.l. Ashfall was reported in Severo-Kurilsk on 24 and 26 June. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Kilauea | Hawaiian Islands (USA) : During 28 June-4 July 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, from a vent high on the NE flank of the cone, and from a small lava pond (which had many small spattering sites along the margin) in a pit on the W side of the crater. The 61G lava flow, originating from a vent on Pu’u ‘O’o Crater’s E flank, continued to enter the ocean at Kamokuna. A solidified lava ramp extended from the tube exit high on the sea cliff down to the growing delta, whose leading edge was about 100 m from the tube exit on the sea cliff.

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that during 22-24 and 27-28 June a weak thermal anomaly was identified in satellite images at Klyuchevskoy. Explosions on 24 and 26 June generated ash plumes that rose to 5-6 km (16,400-19,700 ft) a.s.l. and drifted 112 km S and SE. 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 wind model data, the Darwin VAAC reported that on 21 June ash plumes from Langila rose 2.1 km (7,000 ft) a.s.l. and drifted almost 95 km NW.

Nishinoshima | Japan : Based on satellite images, pilot observations, and information from JMA, the Tokyo VAAC reported that during 30 June-2 July ash plumes from Nishinoshima rose 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted W and E.

Poas | Costa Rica : OVSICORI-UNA reported low-to-moderate-amplitude tremor with occasional periods of high-frequency volcano-tectonic events detected at Poás during 28-29 June. Webcams recorded intense incandescence at night from the bottom of the crater. A sulfur odor was noted in San Rafael de Poás and Vara Blanca. An event at 1115 on 19 June generated a plume that rose 1 km above the vents. An event at 1450 may have generated a plume, but poor visibility did not allow for confirmation. During 1-4 July frequent but small Strombolian activity ejected incandescent material that fell around vent “A” (Boca Roja). Plumes of water vapor, magmatic gases, and particulates rose at most 500 m from the vents.

Popocatepetl | Mexico : Each day during 28 June-4 July CENAPRED reported 67-240 and steam and gas emissions from Popocatépetl, some of which contained minor amounts of ash. Explosions were detected on 28 June (4), on 30 June (1), on 2 July (5), and on 3 July (1), though cloudy conditions prevented visual confirmation of possible ash, gas, and steam plumes. Minor ashfall on 2 July was noted in Ozumba, Amecameca, Tlalmanalco, Chalco, Ayapango, Tenango del Aire, and San Pedro Nexapa. An explosion at 1145 on 4 July generated an ash plume that rose 2.5 km above the crater rim and drifted W. 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 continued to decline; there was an average of five explosions recorded per day during 26 June-2 July. The explosions were also less energetic. Gas-and-ash plumes rose as high as 1.5 km above the crater rim and drifted more than 30 km SE. Sulfur dioxide flux was as high as 1,472 tons per day, recorded on 1 July.

Sinabung | Indonesia | 3.17°N, 98.392°E | Elevation 2460 m

Based on PVMBG observations, satellite images, and wind data, the Darwin VAAC reported that during 29 June-3 July ash plumes from Sinabung rose 3.3-4.9 km (11,000-16,000 ft) a.s.l. and drifted ESE.

Suwanosejima | Ryukyu Islands (Japan) : Based on JMA notices and satellite-image analyses, the Tokyo VAAC reported that on 2 July ash plumes from Suwanosejima rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted N.

Turrialba | Costa Rica : OVSICORI-UNA reported that during 29 June-4 July seismicity at Turrialba was characterized by low-to-medium amplitude tremor, and a small number of low-amplitude volcano-tectonic and long-period events. Plumes of water vapor, magmatic gases, and occasional ash rose as high as 1 km above the West Crater fumaroles. Incandescence from the main crater was recorded at night. Minor ashfall and a sulfur odor was reported in areas of San José including Rancho Redondo, Goicoechea, Moravia, San Pedro Montes de Oca, and Guadalupe.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week of 28 June – 4 July 2017

Bogoslof | Fox Islands (USA) : AVO reported that an explosion at Bogoslof was detected at 0124 on 30 June and lasted about 20 minutes. A small cloud from the event drifted about 16 km N and by 1815 had dissipated. Seismicity declined afterwards but continued intermittently at low levels. Beginning at 1248 on 2 July a significant explosive event was detected in seismic and infrasound data. The event lasted about 16 minutes, and produced an ash plume that rose as high as 11 km (36,000 ft) a.s.l. and drifted E. AVO raised the Aviation colour Code (ACC) to Red and the Volcano Alert Level (VAL) to Warning. Following the eruption seismicity declined and no signs of volcanic unrest were detected in seismic, infrasound, or satellite data on 3 July; the ACC was lowered to Orange and the VAL was lowered to Watch. The ACC and VAL were again raised to Red and Warning, respectively, following an explosive event that began at 1651 on 4 July and lasted 13 minutes. An eruption cloud rose as high as 8.5 km (28,000 ft) a.s.l. and drifted SE. An 11-minute-long eruption began at 1907 on 4 July, producing a small cloud that rose 9.8 km (32,000 ft) a.s.l. and drifted SE.

Dieng Volcanic Complex | Central Java (Indonesia) : BNPB reported that a phreatic eruption at the Sileri Crater lake (Dieng Volcanic Complex) occurred at 1154 on 2 July, ejecting mud and material 150 m high, and 50 m to the N and S. The event injured 11 of 18 tourists that were near the crater. According to a news article a helicopter on the way to help evacuated people after the event crashed, killing all eight people (four crewmen and four rescuers) on board. PVMBG scientists visited the next day and observed weak white emissions rising 60 m. The report noted other events during the recent past; an event at 1303 on 30 April ejected material 10 m high and 1 m past the crater edge that formed a 1-2 mm thick deposit, and an emission at 0941 on 24 May consisting of gas and black “smoke” that rose 20 m. The Alert Level remained at 1 (on a scale of 1-4) and PVMBG warned the public not to approach Sileri Crater within a 100-m radius.

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was identified in satellite images during 23-24 and 27-28 June. An ash plume drifted 55 km SW on 24 June. Explosions on 26 June generated ash plumes that rose to an altitude of 6 km (19,700 ft) a.s.l. and drifted 165 km SE during 26-27 June. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Reventador | Ecuador : During 28 June-4 July IG reported a high level of seismic activity including explosions, long-period earthquakes, harmonic tremor, and signals indicating emissions at Reventador. During 28 June-1 July plumes of water vapor and ash rose as high as 500 m above the crater rim. A 2-km-long lava flow continued to slowly advance down the NW flank. Incandescent blocks from the crater rolled at most 300 m down the W, SW, and S flanks. Cloudy weather prevented visual observations during 2-4 July.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly was identified daily in satellite images over Sheveluch during 23-30 June. Explosions on 27 June generated ash plumes that rose as high as 10 km (32,800 ft) a.s.l. and drifted 1,400 km SE. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Ulawun | New Britain (Papua New Guinea) : Based on analyses of satellite imagery, the Darwin VAAC reported that on 28 June ash plumes from Ulawun rose to an altitude of 2.7 km (9,000 ft) a.s.l. and drifted W.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 21 June – 27 June 2017

Bagana | Bougainville (Papua New Guinea) : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that on 22 and 25 June ash plumes from Bagana drifted NW at an altitude of 2.1 km (7,000 ft) a.s.l.

Bezymianny | Central Kamchatka (Russia) : KVERT reported that a powerful explosion at Bezymianny on 16 June generated an ash plume that rose as high as 12 km (39,400 ft) a.s.l. and drifted 700 km E and SE. Nighttime incandescence from the lava dome was observed at night afterwards, and a lava flow emerged from the W flank of the dome. A thermal anomaly was identified daily in satellite images during 16-23 June. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Cleveland | Chuginadak Island (USA) : AVO reported that there have been no detections of anomalous seismicity or infrasound at Cleveland since a brief explosion on 16 May. Satellite-based evidence of continuing lava effusion was observed on 7 June but since then surface temperatures had become weaker. On 26 June AVO lowered the Aviation colour Code to Yellow and the Volcano Alert Level to Advisory.

Dukono | Halmahera (Indonesia) : Based on analyses of satellite imagery, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 21-27 June ash plumes from Dukono rose to altitudes of 1.5-2.1 km (5,000-7,000 ft) a.s.l. and drifted in multiple directions.

Ebeko | Paramushir Island (Russia) : Based on observations by residents of Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, KVERT reported that explosions on 17 and 21 June 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).

Kilauea | Hawaiian Islands (USA) : During 21-27 June 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, from a vent high on the NE flank of the cone, and from a small lava pond (which had many small spattering sites along the margin) in a pit on the W side of the crater. The 61G lava flow, originating from a vent on Pu’u ‘O’o Crater’s E flank, continued to enter the ocean at Kamokuna. Field observations on 31 May revealed that the lava delta had grown to an area of approximately 0.01 square kilometers. A solidified lava ramp extended from the tube exit high on the sea cliff down to the delta, whose leading edge was about 100 m from the tube exit on the sea cliff. Lava flows from the upper portion of the flow field continued to advance downslope, producing surface flows above the pali.

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that during 16-17 June a weak thermal anomaly was identified in satellite images at Klyuchevskoy. Explosions generated ash plumes that rose to 6-7 km (19,700-23,000 ft) a.s.l. and drifted about 300 km E and W during 16-17 and 22 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 wind model data, the Darwin VAAC reported that on 21 June ash plumes from Langila rose 2.1 km (7,000 ft) a.s.l. and drifted NW.

Poas | Costa Rica : OVSICORI-UNA reported low-amplitude tremor with occasional periods of low-amplitude long-period events detected at Poás during 20-25 June. Plumes of reddish-coloured ash, water vapor, and magmatic gases were recorded rising as high as 500 m above two vents during 20-21 June. Magmatic gases and water vapor plumes rose as high as 1 km above the vents the rest of the period.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya decreased from the previous week; there was an average of 15 explosions recorded per day during 19-25 June. The explosions were also less energetic. Gas-and-ash plumes rose as high as 3.5 km above the crater rim and drifted more than 40 km S. The MIROVA system detected as many as 10 thermal anomalies, spread over the SE, N, and NE flanks. Sulfur dioxide flux was as high as 5,700 tons per day, recorded on 24 June.

Sinabung | Indonesia | 3.17°N, 98.392°E | Elevation 2460 m

Based on PVMBG observations, satellite images, and wind data, the Darwin VAAC reported that during 21-27 June ash plumes from Sinabung rose 3-5.2 km (10,000-17,000 ft) a.s.l. and drifted in multiple directions.

Stromboli | Aeolian Islands (Italy) : INGV reported that during 22-26 June explosions at the N1 vent, one of two vents that comprise Stromboli’s N Area, ejected material as high as 200 m above the vent. Explosive activity at the second vent, N2, ejected tephra 150 m high that fell within the crater terrace as well as beyond the crater rim. Intense spattering at N2 was noted on 26 June. Explosions from the N Area vents occurred at a rate of 10-14 events per hour. Vent C in the CS Area discontinuously puffed, and spattering also occurred on 26 June. Explosions from the S1 vents (also part of the CS Area) ejected tephra 150 m high. Explosions from the CS Area occurred between 5 and 10 events per hour.

Turrialba | Costa Rica : OVSICORI-UNA reported that during 20-25 June seismicity at Turrialba was characterized by low-to-medium amplitude tremor, and a small number of low-amplitude volcano-tectonic and long-period events. Plumes of water vapor and magmatic gases rose as high as 1 km above the crater. The gases were strongly incandescent at night during 22-23 June.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week of 21 June – 27 June 2017

Bogoslof | Fox Islands (USA) : AVO reported that slightly elevated surface temperatures at Bogoslof were identified in satellite images on 23 June, and steam emissions were occasionally observed the previous week. Beginning at 1649 on 23 June a significant explosive event was detected in seismic and infrasound data that lasted about 10 minutes. It produced an ash plume that rose as high as 11 km (36,000 ft) a.s.l. and drifted 400-490 km E. The event prompted AVO to raise the Aviation colour Code (ACC) to Red and the Volcano Alert Level (VAL) to Warning. Four additional explosions were detected, during 1918-1924, 2013-2021, 2104-2112, and 2152-2155, though any resulting ash plumes were not detected above the cloud deck at 8.5-9.1 km (28,000-30,000 ft) a.s.l. On 25 June the ACC was lowered to Orange and the VAL was lowered to Watch. At 1645 on 26 June an eruption which lasted about 14 minutes produced an ash plume that rose 7.6 km (25,000 ft) a.s.l. Seismic and lighting data indicated that a significant explosion began at 0317 on 27 June, prompting AVO to raise the ACC to Red and the VAL to Warning. The event lasted 14 minutes, and produced an ash plume that rose 9.1 km (30,000 ft) a.s.l. and drifted NW. The ACC was lowered to Orange and the VAL was lowered to Watch later that day.

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

Pavlof | United States : AVO reported that no unusual activity was detected in seismic or infrasound data at Pavlof during 21-26 June. Weakly elevated surface temperatures were identified in satellite images during 21-22 June, and a few clear webcam views revealed minor steaming. The Aviation colour Code remained at Yellow and the Volcano Alert Level remained at Advisory.

Reventador | Ecuador : IG reported that during the previous months activity at Reventador was characterized by an average of 50 explosions per day and long-period earthquakes indicating fluid movement. Ash plumes from explosions rose as high as 2 km above the crater rim, and small pyroclastic flows descended the flanks in almost all directions. However, at 1701 on 22 June the pattern of activity changed. Seismic signals indicating emissions became continuous, and spasmodic tremor emerged which was composed of numerous small explosions. Concurrent to the change in seismicity, small-to-moderate pyroclastic flows descended 4 km down the NE flank, and plumes with low-to-moderate ash content rose 2.5 km and drifted W. Pyroclastic-flow deposits were also noted in the upper basin of El Reventador river, E of the cone. During 22-23 June incandescent blocks rolled 500 m down the flanks, steam-and-ash plumes rose 2 km, and several pyroclastic flows traveled 900 m NE. Cloud cover sometimes prevented visual observations during 24-27 June though sometimes gas-and-ash plumes were seen rising no higher than 500 m above the crater rim. Incandescent blocks continued to descend the flanks, traveling as far as 650 m. “Cannon shot” sounds were heard at night during 24-25 June. During 26-27 June several episodes of incandescence at the crater were noted, and a lava flow traveled 2 km down the NE flank.

Rincon de la Vieja | Costa Rica : OVSICORI-UNA reported that at 1456 on 23 June a phreatic eruption at Rincón de la Vieja ejected sediment onto the upper N flank and generated a plume that rose 1-2 km above the summit. The plume dispersed sediments to the W and NW, near the Von Seebach crater (about 3 km SW of the active crater).

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly was identified daily in satellite images over Sheveluch during 16-23 June. Explosions on 17 June generated ash plumes that rose as high as 7 km (23,000 ft) a.s.l. and drifted 300 km E. Strong explosions the next day produced ash plumes that rose as high as 10 km (32,800 ft) a.s.l. and drifted 1,500 km ESE. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Ulawun | New Britain (Papua New Guinea) : RVO reported that during 1 May-23 June white plume rose from Ulawun. Seismicity was low (and dominated by small low-frequency earthquakes) although RSAM values slowly increased and then spiked on 13 June. Ash emissions began on 11 June and then became dense during 21-23 June. Based on analyses of satellite imagery, the Darwin VAAC reported that during 24-26 June ash plumes rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted W.

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 14 June – 20 June 2017

Aira | Kyushu (Japan) : JMA reported that an event at Showa Crater (at Aira Caldera’s Sakurajima volcano) at 1208 on 15 June generated an ash plume that rose 2.8 km above the crater rim. 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 on 14 June an ash plume from Bagana drifted W at an altitude of 2.1 km (7,000 ft) a.s.l. No ash was identified in inages later that day.

Bezymianny | Central Kamchatka (Russia) : On 15 June KVERT reported that the temperature of a thermal anomaly identified in satellite images had increased, and that the webcam recorded a gas-and-steam plume rising above Bezymianny to 4 km (13,100 ft) a.s.l. and drifted SSE. Hot avalanches of material originated from the lava dome. An explosive event began at 1653 on 16 June, producing an ash cloud 28 x 25 km in size that drifted NE. The Aviation colour Code was raised to Red (the highest level on a four-colour scale), but lowered back down to Orange about 5 hours later. At 2110 the ash cloud was 212 x 115 km in size and drifting E; the leading edge of the cloud was about 245 km E.

Cleveland | Chuginadak Island (USA) : AVO reported that no unusual activity at Cleveland had been detected in seismic or infrasound data during 14-20 June. Minor steaming from the summit was recorded by a webcam during 17-18 June, and slightly elevated surface temperatures were identified in a satellite image acquired on 19 and 20 June. 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 14-20 June ash plumes from Dukono rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted in multiple directions.

Ebeko | Paramushir Island (Russia) : Based on observations by residents of Severo-Kurilsk (Paramushir Island) about 7 km E of Ebeko, KVERT reported that explosive activity continued at the volcano during 9-16 June. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Fuego | Guatemala : INSIVUMEH reported that during 13-14 June explosions at Fuego generated shock waves detected within 10 km, and block avalanches descended the Ceniza (SSW), Taniluyá (SW), Santa Teresa (SW), and Trinidad (S) ravines. On 18 June heavy rain triggered a 20-m-wide, 1.5-m-deep lahar that traveled down the El Jute (SE) ravine, carrying tree trunks and blocks as large a 2 m in diameter. Explosions during 18-20 June produced ash plumes that rose as high as 950 m above the crater and drifted 8-12 km S, SW, and W. Ashfall was noted in areas downwind including Morelia (9 km SW), Santa Sofía (12 km SW), Finca Palo Verde, El Porvenir (8 km ENE), Sangre de Cristo (8 km WSW), and Panimaché I and II (8 km SW). Incandescent material was ejected 100-200 m above the crater rim, and caused avalanches of material that traveled into the Ceniza, Taniluyá, Trinidad, and Santa Teresa drainages.

Ibu | Halmahera (Indonesia) : Based on PVMBG observations, satellite images, and wind data, the Darwin VAAC reported that during 14 and 17-19 June ash plumes from Ibu rose 1.5-1.8 km (5,000-6,000 ft) a.s.l. and drifted S, SW, W, and N.

Kilauea | Hawaiian Islands (USA) : During 14-20 June 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, from a vent high on the NE flank of the cone, and from a small lava pond (which had many small spattering sites along the margin) in a pit on the W side of the crater. The 61G lava flow, originating from a vent on Pu’u ‘O’o Crater’s E flank, continued to enter the ocean at Kamokuna. Field observations on 31 May revealed that the lava delta had grown to an area of approximately 0.01 square kilometers. A solidified lava ramp extended from the tube exit high on the sea cliff down to the delta, whose leading edge was about 100 m from the tube exit on the sea cliff. Lava flows from the upper portion of the flow field continued to advance downslope, producing surface flows above and on the pali.

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that during 9-16 June explosions at Klyuchevskoy generated ash plumes that rose to 6-7 km (19,700-23,000 ft) a.s.l. and drifted about 580 km SE and SW. A weak thermal anomaly was identified in satellite images during 11-16 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 wind model data, the Darwin VAAC reported that on 14 June ash plumes from Langila rose 1.8 km (6,000 ft) a.s.l. and drifted WNW. On 20 June an ash plume drifted NW at an altitude of 2.1 (7,000 ft) a.s.l.

Poas | Costa Rica : OVSICORI-UNA reported that during 13-15 June gas emissions from Poás rose no higher than 500 m above the crater rim and drifted N. During breaks in weather, observers near the crater on 16 June noted ash emissions rising less than 1 km above the crater rim and drifting N. Ash emissions from events at 1340 on 18 June, and 1100 and 1350 on 20 June, rose less than 1 km.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya slightly decreased from the previous week; there was an average of 26 explosions recorded per day during 12-18 June. Gas-and-ash plumes rose as high as 3.7 km above the crater rim and drifted more than 40 km SW. The MIROVA system detected nine thermal anomalies, spread over the SE, N, and NW flanks. Sulfur dioxide flux was as high as 3,557 tons per day on 14 June.

Sinabung | Indonesia : Based on PVMBG observations, satellite images, and wind data, the Darwin VAAC reported that during 14-17 and 19 June ash plumes from Sinabung rose 3-6.4 km (10,000-21,000 ft) a.s.l. and drifted in multiple directions.

Turrialba | Costa Rica : OVSICORI-UNA reported that during 14-15 June gas emissions at Turrialba sometimes contained ash and rose no higher than 300 m above the crater. Events at 0620 and 1405 on 16 June generated ash plumes that rose 500 m and drifted NW, and 200 m and drifted S, respectively. Passive ash emissions during 19-20 June rose as high as 1 km and drifted in multiple directions.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week of 14 June – 20 June 2017

Bogoslof | Fox Islands (USA) : AVO reported that elevated surface temperatures and a small steam emission at Bogoslof were identified in satellite images during 13-14 June. Weakly elevated surface temperatures were detected on 16 June, and a 13-km-long steam plume was visible on 18 June. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was identified in satellite images during 10-12 and 14-15 June. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Pavlof | United States : AVO reported that seismicity at Pavlof had declined since the small increase on 7 June, and no unusual activity was observed in seismic or infrasound data through 20 June. Minor steam emissions occasionally rose from the summit crater. Satellite images showed an approximately 55 km-long steam plume drifting W on 14 June, and a thermal anomaly during 15-16 and 20 June. The Aviation colour Code remained at Yellow and the Volcano Alert Level remained at Advisory.

Rincon de la Vieja | Costa Rica : OVSICORI-UNA reported that on 15 June a diffuse plume of mainly water vapor rose 50 m above Rincón de la Vieja’s crater rim. A small hydrothermal explosion from the crater with the highly acidic lake was detected around noon on 18 June. In a report posted the next day OVSICORI-UNA noted that seismicity was characterized by low-frequency events, volcano-tectonic events, and tremor with intensifying amplitude; the seismic patterns were similar to those that preceded the phreatomagmatic events on 23 May and 11 June, though the recent seismicity was not as energetic.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that during 10-13 June explosions at Sheveluch produced ash plumes that rose as high as 8 km (26,200 ft) a.s.l. and drifted 1,500 km SE and NW. At 0425 on 15 June powerful explosions generated ash plumes that rose as high as 12 km (39,400 ft) a.s.l. The Aviation colour Code was raised to Red (the highest level on a four-colour scale), and then back down to Orange at the end of the day. Ash plumes drifted 1,000 km NE and SW during 15-16 June. Ash fell in Klyuchi (50 km SW), Maiskoe, Kozyrevsk (115 km SW), and Atlasovo (160 km SW).

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 7 June – 13 June 2017

Aira | Kyushu (Japan) : JMA reported four events at Showa Crater (at Aira Caldera’s Sakurajima volcano) during 5-12 June, one of which was explosive. Material was ejected 800 m away the crater rim. Ash plumes rose as high as 3.2 km on 6 June and 1.9 km on 10 June. A very small event occurred at Minamidake summit crater on 5 June. The Alert Level remained at 3 (on a 5-level scale).

Asamayama | Honshu (Japan) : JMA stated that activity at Asama had been progressively increasing. During 2-5 June a plume rose less than 400 m above the active crater. Weak incandescence from the summit crater was recorded at night with a webcam. Sulfur dioxide flux was a little higher than 900 tons per day when measured on 2 June. The Alert Level remained at 2 (on a scale of 1-5).

Bagana | Bougainville (Papua New Guinea) : Based on analyses of satellite imagery and model data, the Darwin VAAC reported that during 7-8 and 14 June ash plumes from Bagana rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 65 km SW, W, and NW.

Cleveland | Chuginadak Island (USA) : AVO reported that on 6 June small low-frequency earthquakes at Cleveland were recorded by the seismic network. Elevated surface temperatures identified in satellite images during 6-7 June were consistent with lava effusion at the summit crater. No volcanic activity was detected in seismic, infrasound, or cloudy satellite images during 8-13 June, though AVO noted that lava effusion may have been occurring. A thermal anomaly was identified in satellite images during 12-13 June. 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 7-14 June ash plumes from Dukono rose to altitudes of 1.8-2.1 km (6,000-7,000 ft) a.s.l. and drifted in multiple directions. Ash plumes drifted as far as 140 km E on 7 June.

Ebeko | Paramushir Island (Russia) : Based on observations by residents of Severo-Kurilsk (Paramushir Island) about 7 km E of Ebeko, KVERT reported that explosive activity continued at the volcano during 2-9 June. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Fuego | Guatemala : INSIVUMEH reported that during 8-9 June explosions at Fuego generated ash plumes that rose as high as 1.1 km above the crater rim and drifted 15 km W, NW, and N. Rumbling was noted, and block avalanches descended multiple ravines. Lahars traveled down several ravines on the SE, S, and SW flanks, especially down the Pantaleón (W) ravine. On 10 June at 1150 a lahar descended the Ceniza (SSW) drainage, carrying blocks 1 m in diameter. The lahar was 15-18 m wide and as deep as 3 m. During 10-11 June explosions produced ash plumes that rose 750-1,050 m and drifted 12-15 km W, NW, and N. Shock waves from some of the explosions were detected. Two hot lahars descended the flanks on 13 June. The first one traveled down the Pantaleón river and was 35 m wide and 2.5-3 m deep, and carried trees and blocks 2-3 m in diameter. The second lahar descended the Ceniza and was 25 m wide and 3 m deep, and carried blocks up to 2 m in diameter.

Ibu | Halmahera (Indonesia) : Based on PVMBG observations, webcam and satellite images, and wind data, the Darwin VAAC reported that during 9-12 and 14 June ash plumes from Ibu rose 1.5-1.8 km (4,800-6,000 ft) a.s.l. and drifted N, W, and SSW.

Kilauea | Hawaiian Islands (USA) : During 7-13 June 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, from a vent high on the NE flank of the cone, and from a small lava pond (which had many small spattering sites along the margin) in a pit on the W side of the crater. The 61G lava flow, originating from a vent on Pu’u ‘O’o Crater’s E flank, continued to enter the ocean at Kamokuna. Field observations on 31 May revealed that the lava delta had grown to an area of approximately 0.01 square kilometers. A solidified lava ramp extended from the tube exit high on the sea cliff down to the delta, whose leading edge was about 100 m from the tube exit on the sea cliff.

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that during 2-9 June explosions at Klyuchevskoy generated ash plumes that rose to 5 km (16,400 ft) a.s.l. and drifted about 325 km NE, SE, and SW. A weak thermal anomaly was identified in satellite images on 4 and 8 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 wind model data, the Darwin VAAC reported that on 7 June ash plumes from Langila rose 2.1 km (7,000 ft) a.s.l. and drifted over 45 km NW. On 14 June ash plumes rose 1.8 km (6,000 ft) a.s.l. and drifted WNW.

Poas | Costa Rica :OVSICORI-UNA reported that during 7-13 June seismicity at Poás was characterized by low-amplitude tremor, discrete volcano-tectonic events, low-frequency events, and some periods of small long-period events with low amplitude. During 7-8 June the webcam recorded strong emissions of water vapor, magmatic gases, and particulates. A sulfur odor was reported in Alajuela, San Ramon, and Barva, and incandescence in the area of the crater was recorded at night. OVSICORI-UNA noted that during 8-9 June a plume of water vapor, magmatic gases, and particulates rose from two vents; the lake had evaporated and exposed the vents. A minor sulfur odor was reported on the campus of the Universidad Nacional in Heredia. Events at 1610 and 1750 on 11 June generated plumes that rose 300 and 600 m above the crater, respectively. Plumes from the vents rose 1 km during 12-13 June. A sulfur odor was noted in Quesada, Santa Ana, San José de Alajuela, and San Juanillo Naranjo.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya slightly decreased from the previous week; there was an average of 31 explosions recorded per day during 5-11 June. The number and magnitude of long-period and hybrid events were moderate and low, respectively. Levels of long-period events were moderate and hybrid events were low. Gas-and-ash plumes rose as high as 2.8 km above the crater rim and drifted more than 30 km E and SE. The MIROVA system detected four thermal anomalies, spread over the SE, N, and NW flanks. Sulfur dioxide flux was as high as 3,392 tons per day on 6 June.

Sinabung | Indonesia : Based on PVMBG observations, webcam and satellite images, and wind data, the Darwin VAAC reported that during 12-14 June ash plumes from Sinabung rose 3.4-5.5 km (11,000-18,000 ft) a.s.l. and drifted W and S.

Turrialba | Costa Rica : OVSICORI-UNA reported that tremor amplitude at Turrialba fluctuated from low to medium levels during 7-13 June. Periods of small volcano-tectonic events and many small-amplitude long-period events were also recorded. Plumes of gas and water vapor rose as high as 1 km above the vent and drifted mainly NW, W, and SW.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week of 7 June – 13 June 2017

Bogoslof | Fox Islands (USA) : colourAVO reported that a new lava dome at Bogoslof breached the surface of the ocean on or around 6 June, and was the first observation of lava at the surface since the start of the eruption that began in mid-December 2016. The dome was an estimated 110 m in diameter on 7 June, and then grew to 160 m in diameter by 9 June.

An explosive eruption began at 0318 on 10 June with a series of short infrasound signals which then, starting at about 0416, transitioned into several minutes-long continuous seismic and infrasound tremor signals. The events generated an ash-rich cloud that rose to an estimated altitude of 10.4 km (34,000 ft) a.s.l. and drifted NW. The Aviation colour Code (ACC) was raised to Red and the Volcano Alert Level (VAL) was raised to Warning. The eruption ended at 0528. Satellite data indicated that at least part of the volcanic cloud was more ash-rich than most in the current eruption period. On 11 June AVO noted no detectable activity in seismic or infrasound data after the event the day before. The ACC was lowered to Orange and the VAL was lowered to Watch. Satellite image acquired on 10 June and a photograph from an observer aboard a jet aircraft on 11 June suggested that the lava dome was no longer above the surface of the water, and was destroyed during the 10 June event.

A series of explosive events, each lasting 10-30 minutes, began at 1747 on 12 June and ended around 2035. Ash plumes rose 7.6 km (25,000 ft) a.s.l. and drifted SE. The ACC was raised to Red and the VAL was raised to Warning. At 0817 on 13 June a six-minute-long explosion was detected in seismic and infrasound data. A plume was not observed, likely because it was too small or below detection limits. The ACC was lowered to Orange and the VAL was lowered to Watch.

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that a thermal anomaly over Karymsky was identified in satellite images during 3-8 June. Explosions on 8 June generated ash plumes that rose 2-3 km (6,600-9,800 km) a.s.l. and drifted 70 km E, SE, and SW. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Pavlof | United States : On 7 June AVO reported that during the past several days an increase in low-frequency earthquake activity was detected at Pavlof. This kind of activity can sometime precede eruptive episodes. In addition, several short-duration tremor bursts were observed, and a pilot reported a possible ash cloud to 1.2 km (4,000 ft) a.s.l. Infrasound data from instruments on the volcano and from a more distant network in Sand Point showed no evidence of significant explosive activity. AVO noted that since activity prior to eruptions of Pavlof had always been very subtle, they increased the Aviation colour Code to Yellow and the Alert Level to Advisory based on these observations. During 8-9 June gas emissions from the summit were observed in web camera images and by local observers in Cold Bay (60 km SW). AVO noted that vapor emissions (with or without minor amounts of volcanic ash) are common and may occur from the summit vent at any time.

Rincon de la Vieja | Costa Rica : OVSICORI-UNA reported that a small, minute-long, phreatic eruption in Rincón de la Vieja’s crater lake began at 0542 on 11 June. Poor visibility prevented visual confirmation of plume details, though the Washington VAAC reported that a thermal anomaly was present in satellite images. A small seismic signal that lasted less than one minute was recorded at 2106 on 12 June. The signal possibly represented an emission, though it was not confirmed.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that during 3, 5, and 7-8 June powerful explosions at Sheveluch generated ash plumes that rose as high as 8 km (26,200 ft) a.s.l. and drifted 1,554 km SW, S, and SE. Pyroclastic flows traveled 10 km. Ashfall was reported in Klyuchi Village (50 km SW) on 8 June. A thermal anomaly was identified daily in satellite images. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 31 May – 6 June 2017

Aira | Kyushu (Japan) : JMA reported 15 events at Showa Crater (at Aira Caldera’s Sakurajima volcano) during 22-29 May, two of which were explosive. Material was ejected as high as 800 m above the crater rim. Ash plumes rose as high as 3.4 km on 31 May and 3 km on 2 June. Very small events occurred at Minamidake summit crater during 4-5 June. 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 on 3 and 5 May ash plumes from Bagana rose to altitudes of 1.5-2.1 km (5,000-7,000 ft) a.s.l. and drifted W and SE.

Bogoslof | Fox Islands (USA) : AVO reported that a short-duration (less than 10 minute) explosion at Bogoslof began at 1842 on 31 May based on seismic and infrasound data. A volcanic cloud identified in satellite images rose 7.3 km (24,000 ft) a.s.l., drifted WNW, and dissipated over the Bering Sea. The explosion was preceded by a several hour-long swarm of very small earthquakes. Seismicity decreased in the hours prior to the explosion and remained below the detection threshold. A sulfur dioxide plume from an explosion on 28 May was visible in satellite data drifting over the Hudson Bay region of Canada on 2 June. A short-duration explosive event at 0750 on 5 June produced a small volcanic cloud observed by a pilot. Low-amplitude tremor was detected in seismic data beginning at about 1229 on 5 June but then decreased to background levels. A vessel in the area reported vigorous steaming and a white plume rising several thousand feet above sea level. A brief explosive event was detected at 0600 on 6 June. The event likely produced a low-level (less than 3 km or 10,000 ft a.s.l.) emission; a possible plume at 1.8 km (6,000 ft) a.s.l. was identified in a satellite image following the detection of the activity in seismic and infrasound data, but quickly dissipated. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Cleveland | Chuginadak Island (USA) : AVO reported that no significant volcanic activity at Cleveland was detected in seismic, infrasound, or cloudy satellite images during 31 May-5 June. The webcam recorded steam emissions during periods of clear weather. Small low-frequency events were recorded by the seismic station located on the flank of the volcano beginning at 0939 on 6 June. The events were consistent with lava-dome growth, but growth could not be visually confirmed. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Colima | Mexico : On 2 June the Centro Universitario de Estudios e Investigaciones de Vulcanologia – Universidad de Colima reported that during the previous week seismic data revealed 21 high-frequency events, 14 long-period events, 1.7 hours of tremor, 12 landslides, and zero explosions. During 25-26 May sulfur dioxide emissions were low at 35-51 tons per day, close to the detectable limits.

Dukono | Halmahera (Indonesia) : Based on analyses of satellite imagery, wind model data, and notices from PVMBG, the Darwin VAAC reported that during 31 May-6 June ash plumes from Dukono rose to altitudes of 1.8-2.4 km (6,000-8,000 ft) a.s.l. and drifted NW, W, SW, and E.

Ebeko | Paramushir Island (Russia) : Based on observations by residents of Severo-Kurilsk (Paramushir Island) about 7 km E of Ebeko, KVERT reported that explosive activity continued at the volcano during 25 May-2 June. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Fuego | Guatemala : INSIVUMEH reported increased activity at Fuego on 1 June, characterized by an increase in the number of explosions (6-7 per hour) and ash plumes rising as high as 950 m above the crater and drifting W. Explosions generated shock waves that rattled structures in multiple areas including Panimaché I and II (8 km SW), Morelia (9 km SW), Santa Sofía (12 km SW), El Porvenir, and Sangre de Cristo (8 km WSW). Incandescent material was ejected as high as 500 m above the crater rim, and caused avalanches of material on the flanks. On 2 June explosions produced ash plumes that rose 550-950 m and drifted 10-12 km W and SW. Shock waves were detected within a radius of 25 km. Incandescent material was ejected 300-500 m high, causing avalanches in the Ceniza (SSW), Taniluyá (SW), and Santa Teresa (W) drainages. During 3-4 June there were 2-4 explosions recorded per hour. Ash plumes rose 650-1,050 m high and drifted 8-10 km W and SW. Weak shock waves rattled nearby buildings. Avalanches from ejected incandescent material continued to descend the three drainages. On 4 June a hot lahar descended the Pantaleón (W) drainage, carrying blocks more than 2 m in diameter, branches, and tree trunks. The lahar was 30 m wide and had a strong sulfur odor. During 4-5 June incandescent material rose 150 m and a lava flow traveled 300 m down the Santa Teresa drainage. On 6 June INSIVUMEH noted that eruptive episode number five had ended, with remnant lava flows in the Santa Teresa (2 km long) and Ceniza (3 km long) drainage. Explosions generated ash plumes that rose 950 m and drifted 15 km W and NW.

Ibu | Halmahera (Indonesia) : PVMBG reported that eruptions at Ibu on 1 and 5 June generated ash plumes that rose 150-250 m above the crater and drifted N and SE, respectively.

Kilauea | Hawaiian Islands (USA) : During 31 May-6 June 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, from a vent high on the NE flank of the cone, and from a small lava pond (which had many small spattering sites along the margin) in a pit on the W side of the crater. The 61G lava flow, originating from a vent on Pu’u ‘O’o Crater’s E flank, continued to enter the ocean at Kamokuna. Field observations on 31 May revealed that the lava delta had grown to an area of approximately 0.01 square kilometers. A solidified lava ramp extended from the tube exit high on the sea cliff down to the delta, whose leading edge was about 100 m from the tube exit on the sea cliff.

Klyuchevskoy | Central Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Klyuchevskoy was identified in satellite images during 27 and 30-31 May and 2 June. Explosions during 1-2 June generated ash plumes that rose to 6 km (19,700 ft) a.s.l. and drifted about 400 km SSE. Ash plumes drifted over Petropavlovsk-Kamchatsky and Elizovo. 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 wind model data, the Darwin VAAC reported that on 1 June ash plumes from Langila rose 1.8 km (6,000 ft) a.s.l. and drifted N and NW.

Manam | Papua New Guinea : RVO reported that although weather clouds often obscured views of Manam during 1-7 June white emissions were periodically seen rising from Southern Crater and Main Crater. Seismicity was very low. The Alert Level remained at Stage 1.

Planchon-Peteroa | Central Chile-Argentina border : Based on Observatorio Volcanológico de los Andes del Sur (OVDAS) – SERNAGEOMIN observations, ONEMI reported on 17 May that the number and magnitude of earthqaukes at Planchón-Peteroa had gradually declined during the past months, reaching baseline levels. Minor to no surface activity was noted. OVDAS-SERNAGEOMIN lowered the Alert Level to Green (the lowest level on a three-colour scale), and ONEMI canceled the Yellow Alert for the communities of Molina (66 WNW), Curicó (68 km NW), Romeral (75 km NW), and Teno (68 km NW) that had been in place since 1 July 2016.

Poas | Costa Rica : OVSICORI-UNA reported that tremor amplitude at Poás fluctuated from low to medium levels during 30-31 May, often associated with the vigor of emissions of water vapor, magmatic gases, and material from vents. An event at 1200 on 2 June generated a plume consisting of water vapor, gases, and minor amounts of ash that rose 600 m above the crater. Another event recorded at 1353 could not be confirmed visually due to weather conditions. An event at 0858 on 6 June generated a plume that rose 1 km.

Popocatepetl | Mexico : Each day during 31 May-2 June CENAPRED reported 51-78 and steam and gas emissions from Popocatépetl; the daily count increased to 144-276 during 2-5 June. Explosions were detected during 31 May-1 June (1-2 per day) and during 2-5 June (13-22 per day) though cloudy conditions prevented visual confirmation of ash, gas, and steam plumes. Observers noted material being ejected 200 m from the crater on 3 June. Crater incandescence was visible on some nights. 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 for the second week in a row explosive activity at Sabancaya slightly increased from the previous week; there was an average of 47 explosions recorded per day during 29 May-4 June. Seismicity was dominated by long-period events, and the number and magnitude of hybrid events were low. Gas-and-ash plumes rose as high as 3 km above the crater rim and drifted more than 40 km E and SE. The MIROVA system detected five thermal anomalies, spread over the SE, N, and NW flanks. Sulfur dioxide flux was as high as 1,703 tons per day on 3 June.

Sinabung | Indonesia : Based on PVMBG observations, webcam and satellite images, and wind data, the Darwin VAAC reported that during 31 May-5 June ash plumes from Sinabung rose 3.4-5.5 km (11,000-18,000 ft) a.s.l. and drifted in multiple directions.

Turrialba | Costa Rica : OVSICORI-UNA reported that volcano-tectonic amplitude at Turrialba fluctuated from low to moderate levels during 30-31 May. Plumes of water vapor, magmatic gases, and material rose no higher than 300 m above the crater rim, sporadically contained ash, and drifted NW. On 3 June at 1930 an event produced an ash plume that rose 300 m and drifted SW. The report noted that during the previous week ash emissions had been sporadic and not generated by explosions.

Volcanos

Roundup of Global Volcanic Activity – New Activity for the week of 31 May – 6 June 2017

Bulusan | Luzon (Philippines) : PHIVOLCS reported that a minor phreatic eruption at Bulusan occurred at 1029 on 5 June and was recorded by the seismic network for 12 minutes. The eruption could not be visually observed due to dense weather clouds covering the summit. Minor ashfall, a sulfuric odor, and rumbling sound were reported in barangays Monbon and Cogon in Irosin, while sulfuric odor was noted in barangay Bolos, Irosin. The Alert Level remained at 1, indicating abnormal conditions and a 4-km-radius Permanent Danger Zone (PDZ).

Copahue | Central Chile-Argentina border : OVDAS-SERNAGEOMIN reported that webcams recorded an increase in ash emissions at Copahue on 4 June. There were no significant changes in the magnitude or number of earthquakes recorded by the seismic network. The report noted that due to inclement weather making visual observations difficult, the observatory did not know if the ash emission began in the early hours of 4 June, or the day before. The Alert Level was raised to Yellow (the second lowest on a four-colour scale); SERNAGEOMIN recommended no entry into a restricted area within 1 km of the crater.

Karymsky | Eastern Kamchatka (Russia) : Based on Tokyo VAAC data, KVERT reported that an explosive eruption at Karymsky began at 0040 on 4 June. An ash plume rose 3 km (9,800 ft) a.s.l. and drifted over 40 km NE. The Aviation colour Code was raised to Orange (the second highest level on a four-colour scale). Less than four hours later ash plumes rose 2 km (6,600 ft) a.s.l. and drifted 85 km ENE. The VAAC reported that a possible ash plumes rose 4 km 13,000 ft) a.s.l. during 5-6 June and drifted E.

Marapi | Indonesia : PVMBG reported four explosions at Marapi on 4 June, each lasting less than one minute. The explosions occurred at 1001, 1011, 1256, and 1550, and produced dense ash-and-steam plumes that rose 300 m, at least 700 m, 200 m, and 250 m above the crater, respectively. The plumes drifted E. Ejected bombs were deposited around the crater. Seismicity increased after the explosions. Minor ashfall was reported in the Pariangan District (8 km SSE), Tanah Datar Regency. The Alert Level remained at 2 (on a scale of 1-4). Residents and visitors were advised not to enter an area within 3 km of the summit.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that during 26-27 and 31 May powerful explosions at Sheveluch generated ash plumes that rose 8 km (26,200 ft) a.s.l. and drifted 550 km ESE and about 650 km WSW. A thermal anomaly was identified in satellite images during 26 May-2 June. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Volcanos

Roundup of Global Volcanic Activity – Ongoing Activity for the week of 24 May – 30 May 2017

Aira | Kyushu (Japan) : JMA reported 22 events at Showa Crater (at Aira Caldera’s Sakurajima volcano) during 22-29 May, seven of which were explosive. The explosions ejected material as high as 800 m above the crater rim, and as far away as 500 m. Ash plumes rose as high as 3.3 km on 23 May and 3.4 km on 29 May. Crater incandescence was detected on 25 May. A very small event occurred at Minamidake summit crater on 26 May. The Alert Level remained at 3 (on a 5-level scale).

Bezymianny | Central Kamchatka (Russia) : On 26 May KVERT reported that after an explosive eruption at Bezymianny on 9 March, and the effusion of several lava flows onto the dome flanks, the volcano became quiet. Gas-and-steam emissions continued, along with a thermal anomaly identified in satellite images. The Aviation colour Code was lowered to Yellow (the second lowest level on a four-colour scale).

Bogoslof | Fox Islands (USA) : An eruption at Bogoslof began at 1416 on 28 May prompting AVO to raise the Aviation colour Code (ACC) to Red and the Volcano Alert Level (VAL) to Warning. Pilot and satellite observations indicated than ash plumes rose at least 10.7 km (35,000 ft) a.s.l. and possibly as high as 13.7 km (45,000 ft) a.s.l. An observer on Unalaska Island reported seeing a large white-gray mushroom cloud form over Bogoslof, with ashfall to the W. The event lasted 50 minutes. On 29 May the ash cloud continued to drift NE. No detectable activity was observed in data from seismic or infrasound stations located on nearby Islands, and no new activity has been observed in satellite data. The ACC was lowered to Orange and the VAL was lowered to Watch.

Cleveland | Chuginadak Island (USA) : AVO reported that no significant volcanic activity at Cleveland was detected in seismic, infrasound, or mostly cloudy satellite images during 24-30 May. The webcam periodically recorded steam emissions. The Aviation colour Code remained at Orange and the Volcano Alert Level remained at Watch.

Colima | Mexico : On 26 May the Centro Universitario de Estudios e Investigaciones de Vulcanologia – Universidad de Colima reported that during the previous week seismic data revealed 36 high-frequency events, 20 long-period events, 2.6 hours of tremor, 12 landslides, and three low-intensity explosions. On 23 May sulfur dioxide emissions were below detectable limits (8.6 tons/day). A short-lived, low-amplitude episode of tremor was detected on 24 May.

Dukono | Halmahera (Indonesia) : Based on analyses of satellite imagery and wind model data the Darwin VAAC reported that during 24-30 May ash plumes from Dukono rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted NW, W, and SW. Plumes drifted over 230 km W on 27 May.

Ebeko | Paramushir Island (Russia) : KVERT reported that during 23-24 May explosions at Ebeko were observed by residents of Severo-Kurilsk (Paramushir Island) about 7 km E. Ash plumes 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).

Kilauea | Hawaiian Islands (USA) : During 24-30 May HVO reported that the lava lake continued to rise, fall, and spatter in Kilauea’s Overlook crater. A portion of the N Overlook crater wall collapsed into the lake, causing lake agitation and depositing tephra at the Hawaiian Volcano Observatory and Jaggar Museum. Webcams recorded incandescence from long-active sources within Pu’u ‘O’o Crater, from a vent high on the NE flank of the cone, and from a small lava pond in a pit on the W side of the crater. The 61G lava flow, originating from a vent on Pu’u ‘O’o Crater’s E flank, continued to enter the ocean at Kamokuna adding to a growing delta. Narrow cracks on the delta parallel to the coast were noted. Surface lava flows were active above and on the upper slopes of the pali.

Langila | New Britain (Papua New Guinea) : Based on analyses of satellite imagery and wind model data, the Darwin VAAC reported that during 24-27 May ash plumes from Langila rose 2.1-3 km (7,000-10,000 ft) a.s.l. and drifted 75-85 km W and NW.

Manam | Papua New Guinea : RVO reported that Strombolian activity at Manam’s Southern Crater during 13-14 and 18 May generated lava flows that descended the SW valley. Lava flows traveled to 180-220 m elevation during 13-14 May but were significantly small on 18 May. Activity was low on other days during 13-26 May; ash plumes rose from the crater during 15-18 May. Conditions were quiet at Main Crater. RVO recommended that the Alert Level be lowered to Stage 1.

Nevado del Ruiz | Colombia : Servicio Geológico Colombiano’s (SGC) Observatorio Vulcanológico y Sismológico de Manizales reported that during 23-29 May seismicity at Nevado del Ruiz continued to indicate unrest. Five episodes of drumbeat seismicity (low-energy long-period events) were recorded between 1343 and 1930 on 29 May, likely signifying growing lava domes. Significant amounts of water vapor and gas continued to be emitted. Gas, steam, and ash plumes rose 880 m above the crater rim on 27 May and drifted NW and SW. A thermal anomaly was identified on 28 May. The Alert Level remained at III (Yellow; the second lowest level on a four-colour scale).

Pacaya | Guatemala : INSIVUMEH reported nighttime crater incandescence and small Strombolian explosions at Pacaya’s Mackenney cone during 27-28 May.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that during 22-28 May explosive activity at Sabancaya slightly increased from the previous week, with an average of 41 explosions detected per day. Seismcity was dominated by long-period events, and the number and magnitude of hybrid events were low. Gas-and-ash plumes rose as high as 2.8 km above the crater rim and drifted more than 30 km E and SE. The MIROVA system detected two thermal anomalies.

Santa Maria | Guatemala : INSIVUMEH reported that during 24-25 May avalanches of material from Santa María’s Santiaguito lava-dome complex traveled short distances down the flanks. During 27-30 May weak explosions generated ash plumes that rose 600-700 m and drifted W and SW. Ashfall was reported in Monte Claro (S).

Sinabung | Indonesia : Based on PVMBG observations, webcam and satellite images, and wind data, the Darwin VAAC reported that during 24-29 May ash plumes from Sinabung rose 3.7-5.8 km (12,000-19,000 ft) a.s.l. and drifted in multiple directions.

Turrialba | Costa Rica : OVSICORI-UNA reported that tremor amplitude at Turrialba fluctuated from low to high levels during 23-30 May, often corresponding to emission characteristics. Periods of volcano-tectonic and long-period events were also recorded. During 24-26 May several passive and sporadic ash emissions rose no higher than 500 m above the vent and drifted NW and SW. Frequent and small explosions during 26-27 May generated ash plumes that rose higher than 500 m above the vent, and ejected material higher than 200 m and no farther than 100 m towards Central Crater. Small explosions during 27-29 May produced ash plumes that rose 300-500 m.