Friday 29 March 2019

Volcanos

Global Volcanic Activity - Ongoing Activity for the week of 20 March - 26 March 2019

Agung | Bali (Indonesia) : PVMBG reported that at 0018 on 21 March an event at Agung was recorded for 1 minute and 47 seconds by the seismic network. Weather conditions prevented visual observations of the summit. 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 during 18-22 March there were two events and one explosion recorded at Minamidake crater (at Aira Caldera’s Sakurajima volcano). Plumes rose at least as high as 1.7 km above the crater rim. Small events occasionally occurred during 22-25 March; crater incandescence was visible at night on 24 March. The Alert Level remained at 3 (on a 5-level scale).

Dukono | Halmahera (Indonesia) : Based on satellite and wind model data, the Darwin VAAC reported that during 20-22 and 24 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. 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 15, 16-19, and 21 March that sent ash plumes up to 4.5 km (14,800 ft) a.s.l. Ash fell in Severo-Kurilsk during 15-16 and 21 March. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Fuego | Guatemala : On 22 March INSIVUMEH reported that activity at Fuego had increased during the previous few days. There were 15-20 explosions per hour producing ash plumes that rose as high as 1.3 km above the summit and drifted 20-30 km E, SE, S, SW, and W. Ashfall was reported in communities downwind including La Rochela, Ceylán, San Andrés Osuna, Las Palmas, Siquinalá, and Santa Lucia Cotzumalguapa (23 km SW). Shock waves vibrated residential structures within 20 km. The explosions also caused avalanches of material from the crater that traveled down the Seca (W), Ceniza (SSW), Taniluyá (SW), Trinidad (S), Las Lajas (SE), and Honda ravines. In the evening on 21 March and early morning hours of 22 March lava fountains rose 350 m above the summit. During 23-26 March explosions occurred at a rate of 15-25 per hour, generating ash plumes that rose as high as 1.2 km and drifted 15-20 km W, S, and SE. Explosions sometimes vibrated nearby residences. Incandescent material was ejected 200-300 m high and caused avalanches of material that traveled down Seca, Taniluyá, Ceniza, Trinidad, Las Lajas, and Honda ravines, sometimes reaching vegetated areas. Ashfall as reported in areas downwind including Panimache I (8 km SW), Morelia (8 km SW), Santa Sofia (12 km SE), La Rochela, and San Andrés Osuna.

Ibu | Halmahera (Indonesia) : The Darwin VAAC reported that a minor ash plume from Ibu rose to an altitude of 2.4 km (8,000 ft) a.s.l., drifted about 17 km NE, and dissipated. An ash plume rose to an altitude of 2.1 km (7,000 ft) a.s.l. later that day, and to 2.4 km on 23 March; both plumes drifted E. 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 visible in satellite images on 17 March. The volcano was quiet or obscured by clouds on the other days during 15-22 March. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Kilauea | Hawaiian Islands (USA) : HVO reported that during the previous several months monitoring data at Kilauea showed relatively low rates of seismicity, deformation, and gas emissions at the summit and East Rift Zone (ERZ) (including the area of the 2018 eruption). As a result, HVO lowered the Volcano Alert Level to Normal and the Aviation colour Code to Green.

Krakatau | Indonesia : PVMBG reported that a total of six explosions at Anak Krakatau were recorded on 18 March, with dense white plumes rising as high as 500 m from the summit. During 18-24 March no other plumes were noted although weather conditions often prevented visual observations. Events were recorded at 0301 and 0305 on 24 March, though ash plumes were not visible. The Alert Level remained at 3 (on a scale of 1-4), and residents were warned to remain outside of the 5-km radius hazard zone from the crater.

Manam | Papua New Guinea : The Darwin VAAC reported that during 19-22 March ash plumes from Manam rose to an altitude of 4.6 km (15,000 ft) a.s.l. and drifted E and SE based on satellite data and ground-based observations.

Merapi | Central Java (Indonesia) : PVMBG reported that the slow extrusion of a lava dome in Merapi’s summit crater continued during 17-24 March. By 21 March the lava dome had grown to an estimated size of 472,000 cubic meters based on analyses of drone footage. 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 as far as 1,500 m down the Gendol drainage during 18-19 and 23 March. 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.

Rincon de la Vieja | Costa Rica : OVSICORI-UNA reported that a small event at Rincón de la Vieja was recorded at 1851 on 19 March.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Sheveluch’s lava dome was identified daily in satellite images during 15-22 March. Strong gas-and-steam emissions containing variable amounts of ash rose 3.5-4 km (11,500-13,100 ft) a.s.l. and drifted 105 km E during 15-17 March. 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 15-22 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 a period of continuous emissions from Turrialba during 20-22 March. The emissions were characterized as white water vapor plumes with periodic pulses of diffuse ash rising 300 m above the vent rim and drifting W and SW. A sulfur odor was noted in Tierra Blanca de Cartago on 22 March. Only water vapor plumes with a low concentration of magmatic gases were visible during 23-26 March.

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