Friday, 16 March 2018

Volcanos

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

Agung | Bali (Indonesia) : PVMBG reported that although there were sometimes foggy conditions during 7-13 March, white plumes were observed rising as high as 600 m above Agung’s crater rim and drifting E. An event at 2332 on 11 March generated an ash plume that rose about 950 m and drifted E. The Alert Level remained at 3 (on a scale of 1-4) and the exclusion zone continued at a 4-km radius.

Aira | Kyushu (Japan) : JMA reported that on 5 March at 2026 an event at Minamidake crater (at Aira Caldera’s Sakurajima volcano) produced an ash plume that rose 1 km above the crater rim, into the clouds. Two explosions were detected on 10 March; one of the events, at 2312, generated ash plumes that rose 1.5 km above the crater rim and ejected material as far as 1.3 km. The Alert Level remained at 3 (on a 5-level scale).

Ambae | Vanuatu : Based on satellite and webcam observations, and model data, the Wellington VAAC reported that during 12-13 March ash plumes from Ambae rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted SW.

Cleveland | Chuginadak Island (USA) : AVO reported that unrest continued at Cleveland during 7-13 March. Elevated surface temperatures were identified in satellite images on 7 March and seismicity slightly increased on 8 March. The Aviation colour Code was lowered to Yellow and the Volcano Alert Level was lowered to Advisory.

Dukono | Halmahera (Indonesia) : Based on analyses of satellite imagery and wind model data, the Darwin VAAC reported that during 7-13 March 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 volcanologists in Severo-Kurilsk (Paramushir Island), about 7 km E of Ebeko, explosions on 6 March generated ash plumes that rose as high as 1.7 km (5,600 ft) a.s.l. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Ibu | Halmahera (Indonesia) : PVMBG reported that although foggy conditions often prevailed at Ibu ash plumes were observed rising 300-600 m above the carter rim and drifting W and S. 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 : RVO reported that emissions from Kadovar’s Main Crater were white from 1 March, until an explosion on 1800 on 5 March was followed by gray emissions through 8 March. The gray plumes rose less than 360 m above the vent and drifted SE. Noises were described as roaring and rumbling during 1-2 and 6-8 March, and booming on 5 March. The lava dome at the SE Coastal Vent continued to grow and rose to 7-8 m above sea level on 1 March, 10-11 m on 2 March, and 10-17 m on 8 March. Dark gray ash plumes rose from the dome. Nighttime incandescence was noted from both Main Crater and the SE vent.

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

Mayon | Luzon (Philippines) : PHIVOLCS reported that during 6-13 March activity at Mayon was characterized by periods of gravity-driven lava advancement, gas-and-steam emissions, lava fountains, and quiescence. Episodes of weak lava fountaining during 6-10 March were accompanied by ash plumes that rose 100-300 m above the crater and drifted mainly SW. Rumbling sounds were audible at least within a 10-km radius. Active lava flows extended 3.3 km, 4.5 km, and 1.9 km long in the Mi-isi (S), Bonga (SE), and Basud (E) drainages, respectively. Steam plumes rose 2.4 km and drifted SW on 10 March. The next day white-and-gray plumes rose 2.5 km and drifted SW. The Alert Level remained at 3 (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.

Nevados de Chillan | Chile : Servicio Nacional de Geología and Minería (SERNAGEOMIN) Observatorio Volcanológico de Los Andes del Sur (OVDAS) reported continuing activity during 16-28 February associated with a low rate of growth of the Gil-Cruz lava dome in Nevados de Chillán’s Nicanor Crater. Continuous gas emissions from the SE-NW-trending fissure on the dome’s surface were punctuated by emission of ash and water vapor that rose no higher than 1.8 km. During an overflight on 22 February observers noted an increased volume of the dome compared to the previous observation. 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.

Popocatepetl | Mexico : CENAPRED reported that each day during 7-13 March there were 105-361 steam and gas emissions from Popocatépetl. Incandescence from the crater was visible at night. Explosions were recorded on 7 March. An explosion at 1042 on 12 March generated an ash plume that rose 1.5 km above the crater rim and drifted SE. The Alert Level remained at Yellow, Phase Two.

Reventador | Ecuador : During 6-13 March IG reported a high level of seismic activity including explosions, long-period earthquakes, harmonic tremor, and signals indicating emissions at Reventador. Steam, gas, and ash plumes sometimes rose higher than 600 m above the crater rim and drifted N, NW, and W. Incandescent blocks rolled as far as 800 m down the flanks. On 13 March a pyroclastic flow traveled 400 m down the S flank. Weather clouds sometimes prevented visual observations.

Sabancaya | Peru : Observatorio Vulcanológico del Sur del IGP (OVS-IGP) and Observatorio Vulcanológico del INGEMMET (OVI) reported that explosive activity at Sabancaya decreased compared to the previous week; explosions averaged 10 per day during 5-11 March. Seismicity was dominated by long-period events, with signals indicating emissions. Gas-and-ash plumes rose 5.4 km above the crater rim and drifted 30 km N, NW, W, and SW. The sulfur dioxide flux was high, at 2,396 tons per day on 9 March. The report noted that the public should not to approach the crater within a 12-km radius.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a weak thermal anomaly over Sheveluch was identified in satellite images on 4 and 6-8 March. The Aviation colour Code remained at Orange.

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