Thursday 14 March 2019

Volcanos

Global Volcanic Activity - New Activity for the week of 6 March - 12 March 2019

Barren Island | Andaman Islands (India) : Based on analysis of satellite imagery and wind data, the Darwin VAAC reported that on 7 March ash plumes from Barren Island rose to an altitude of 1.8 km (6,000 ft) a.s.l. and drifted W and NW, and to an altitude of 1.2 km (4,000 ft) a.s.l. and drifted E and ESE.

Bezymianny | Central Kamchatka (Russia) : KVERT reported that a thermal anomaly over Bezymianny was identified in satellite images during 1-12 March. Strong gas-end-steam emissions continued to rise from the crater. Hot avalanches originating from the top of the lava dome were visible at night. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Karymsky | Eastern Kamchatka (Russia) : KVERT reported that ash plumes from Karymsky were identified in satellite images during 1 and 4-5 March rising as high as 3.5 km (11,500 ft) a.s.l. and drifting 90 km E. A thermal anomaly was also visible on those same days. The Aviation colour Code remained at Orange (the second highest level on a four-colour scale).

Mayon | Luzon (Philippines) : PHIVOLCS reported that during 6-11 March white steam plumes periodically emitted from Mayon drifted WNW, WSW, and SW, and crater incandescence was visible each night. As many as six volcanic earthquakes and two rockfalls per day were recorded by the seismic network. Phreatic events recorded at 0811 on 7 March and 0627 on 8 March generated grayish ash plumes that rose 500 and 300 m above the crater, respectively, and drifted SW. The Alert Level remained at 2 (on a 0-5 scale) and PHIVOLCS reminded residents to stay away from the 6-km-radius Permanent Danger Zone and the 7-km Extended Danger Zone on the SSW and ENE flanks.

Piton de la Fournaise | Reunion Island (France) : During an overflight between 0700 and 0800 on 6 March tourists observed a new active fissure on the NW flank of Piton de la Fournaise’s Piton Madoré, 150 m upstream of the main vent. The fissure likely opened the day before during 0900 and 1900. The tourist report noted that a small cone had formed, and a lava flow was traveling N. In the morning of 7 March at least six new vents were visible, although weather conditions prevented OVPF volcanologists from confirming if they were along a new fissure. During fieldwork on 8 March volcanologists inspected the 5 March fissure and observed a small cone ejecting material up to 10 m above the rim. Lava from the W side flowed a few tens of meters, and a flow from the N side progressed E. The new vents that opened on 7 March were confirmed to be along an E-W trending fissure. The vents were active, each producing 50-m-high lava fountains. The report also noted that samples from the 5 March and 7 March vents had different compositions, though no other details were noted. Lava flows traveled to around 1,000 m elevation. Satellite images showed sulfur dioxide plumes drifting 450-550 km E on 8 March. Lava flows rapidly progressed during 8-9 March; the lava emission rate was variable, ranging up to 25 cubic meters per second (based on satellite data), although since the new fissures opened the highest values (over 50 cubic meters per second) measured the past few days were approximately 10 times higher than the average values recorded during the 2017-2018 eruptions. By 0800 on 9 March the flow front was at an estimated elevation of 650-700 m. After a phase of intense surficial activity during 9-10 March, with lava fountains rising as high as 100 m, lava-flow emissions ceased around 0628 on 10 March and seismicity significantly decreased.

San Cristobal | Nicaragua : INETER reported that a low-energy explosion at San Cristóbal was detected by the seismic network at 1550 on 4 March. The event produced a gas-and-ash plume that rose 400 m above the crater rim and drifted SW.

Tengger Caldera | Eastern Java (Indonesia) : PVMBG reported that on 10 March an eruption at Tengger Caldera’s Bromo cone generated a white, brown, and gray ash plume that, according to a ground observer, rose 600 m and drifted SW. An event at 0600 on 11 March produced a dense gray-to-brown ash plume that rose 600 m and drifted S, SW, and W. The Alert Level remained at 2 (on a scale of 1-4).

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