Volcanos

Global Volcanic Activity - Ongoing Activity for the week of 2 October - 8 October 2019

Aira | Kyushu (Japan) : JMA reported that incandescence from Minamidake crater (at Aira Caldera’s Sakurajima volcano) was occasionally visible at night during 30 September-7 October. The sulfur dioxide emission rate was high, at 2,000 tons/day, measured during fieldwork on 1 October. An explosion was recorded at 0055 on 4 October but weather clouds prevented visual confirmation. Two explosions during 6-7 October generated ash plumes that rose as high as 2.4 km above the crater rim and ejected large blocks 1.1 km away. The Alert Level remained at 3 (on a 5-level scale).

Dukono | Halmahera (Indonesia) : Based on satellite and wind model data, and information from PVMBG, the Darwin VAAC reported that during 2-8 October 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. The Alert Level remained at 2 (on a scale of 1-4), and the public was 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 27 September-4 October that sent ash plumes up to 4 km (13,100 ft) a.s.l. Ash plumes drifted SE, E, and NE. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Fuego | Guatemala : INSIVUMEH reported that there were 10-18 explosions per hour recorded at Fuego during 2-8 October, generating ash plumes that rose as high as 1.1 km above the crater rim and drifted 10-25 km S, SW, W, and NW. Ashfall was reported in several areas downwind including Santa Sofía (12 km SW), Morelia (9 km SW), Panimaché I and II (8 km SW), Finca Palo Verde, San Pedro Yepocapa (8 km NW), and El Porvenir (8 km ENE). Explosions sometimes produced shock waves that rattled houses in nearby communities. Incandescent material was ejected 200-400 m high and caused avalanches of material that occasionally traveled long distances (reaching vegetated areas) down the Seca (W), Taniluyá (SW), Ceniza (SSW), Trinidad (S), El Jute (SE), Las Lajas (SE), and Honda ravines. Lava flows traveled 200 m down the Seca drainage on 6 October and were active in the Santa Teresa (W) drainage on 8 October. Lahars descended the Ceniza, El Mineral, and Seca drainages during 3-7 October, carrying tree branches, trunks, and blocks 1-3 m in diameter.

Hakoneyama | Honshu (Japan) : On 7 October JMA lowered the Alert Level for Hakoneyama to 1 (the lowest level on a 5-level scale), noting that the number of volcanic earthquakes had decreased to background levels after a spike in seismicity was recorded in May. Inflation had been detected but had become almost stagnant after late August. Fumaroles in the Owakudani hot springs area continued to be active, with gas-and-steam plumes rising 100-400 m above their vents.

Ibu | Halmahera (Indonesia) : The Darwin VAAC reported that during 6-7 October ash plumes from Ibu rose to altitudes of 2.1-2.7 km (7,000-9,000 ft) a.s.l. and drifted S and N based on satellite images and weather models. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to stay at least 2 km away from the active crater, and 3.5 km away on the N side.

Karangetang | Siau Island (Indonesia) : PVMBG reported that during 30 September-6 October lava continued to effuse from Karangetang’s Main Crater (S), traveling as far as 1.8 km down the Nanitu, Pangi, and Sense drainages on the SW and W flanks. Sometimes dense white plumes rose to 300 m above the summit. The Alert Level remained at 2 (on a scale of 1-4).

Karymsky | Eastern Kamchatka (Russia) : On 3 October KVERT reported that a weak thermal anomaly over Karymsky continued to be periodically visible in satellite images. Ash explosions were last recorded on 24 September. The Aviation colour Code was lowered to Yellow (the second lowest level on a four-colour scale).

Kerinci | Indonesia : PVMBG reported that at 1253 on 6 October a brown ash emission from Kerinci rose around 600 m above the summit and drifted WSW according to a ground observer. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 3-km exclusion zone.

Krakatau | Indonesia : PVMBG reported that Anak Krakatau’s seismic network recorded one eruptive event during 30 September-6 October. A webcam at the summit recorded diffuse white plumes rising as high as 50 m above the crater rim. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to remain outside of the 2-km-radius hazard zone from the crater.

Manam | Papua New Guinea : RVO reported that white emissions rose from Manam during 1-7 October and variable crater incandescence from Main Crater was visible at night. Seismicity was at low to moderate levels with RSAM values fluctuating around 300 units. The Darwin VAAC reported that during 3-4 October diffuse ash plumes rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted N and NW, based on satellite data and weather models. A thermal anomaly was also visible.

Nevado del Ruiz | Colombia : Servicio Geológico Colombiano’s (SGC) Observatorio Vulcanológico y Sismológico de Manizales reported that during 24 September-1 October seismicity at Nevado del Ruiz increased in both frequency and magnitude compared to the previous week. Steam-and-gas plumes rose as high as 1.4 km above the summit and drifted mainly NW. A tremor pulse recorded at 2353 on 29 September was associated with an ash plume that drifted NW and was observed by Parque Nacional Natural los Nevados (PNNN) officials, SGC staff in the field, and residents of Manizales (25 km NW). Seismicity continued to indicate gas-and-ash emissions during 1-4 October. Beginning at 0138 on 4 October seismicity increased; several ash emissions were visible during the morning in webcam images and by SGC staff in the field. The emissions rose as high has 800 m and drifted mainly NW, causing ashfall locally and in Manizales. The Alert Level remained at 3 (Yellow; the second lowest level on a four-colour scale).

Nevados de Chillan | Chile : ONEMI and SERNAGEOMIN reported that during 2-8 October white-to-gray gas plumes from Nevados de Chillán’s Nicanor Crater rose as high as 1 km above the rim and drifted ESE, S, and SE. Explosions on 2 and 6 October ejected incandescent material onto the flank. The lava flow on the NNE flank ceased advancing around 6 October, and small pyroclastic flows were recorded during 6-8 October. The volcano Alert Level remained at Orange, the second highest level on a four-colour scale. ONEMI maintained an Alert Level Yellow (the middle level on a three-colour scale) for the communities of Pinto, Coihueco, and San Fabián, and stated that the public should stay at least 3 km away from the crater on the SW flank and 5 km away on the ENE flank.

Santa Maria | Guatemala : INSIVUMEH reported that each day during 2-8 October there were as many as five explosions per hour detected at Santa María's Santiaguito lava-dome complex. Ash plumes rose 700-900 m above the complex and drifted SW. Avalanches of material descended the SE and S flanks. Ash fell in Monte Claro (S) on 2 October.

Sheveluch | Central Kamchatka (Russia) : KVERT reported that during 29 September and 1-2 October video and satellite images recorded ash plumes from explosions at Sheveluch rising as high as 9 km (29,500 ft) a.s.l., and a notable pyroclastic flow traveled SE on 1 October. Ash plumes from the events drifted 1,400 km SE and E. On 6 October satellite images showed ash plumes rising to 10 km (32,800 ft) a.s.l. and drifting 430 km NE. The Aviation colour Code was raised to Red (the highest level on a four-colour scale). Later that day the ash plumes were visible in satellite images drifting 1,080 km ENE. The Alert Level was lowered back to Orange.

Tangkubanparahu | Western Java (Indonesia) : PVMBG reported that during 30 September-6 October diffuse white water vapor plumes rose 150 m above the vent on Tangkubanparahu's Ratu Crater floor. The seismic network recorded continuous tremor. The Alert Level remained at 2 (on a scale of 1-4), and the public was warned to stay 1.5 km away from the active crater.