On 5 April, GeoNet reported that the temperature of Ruapehu's summit Crater Lake had been high for a sustained period and was currently between 38 and 39 degrees Celsius. The highest temperature since unrest began in October 2010 was 41 degrees Celsius, measured on 1 March. The report also noted that during the previous few weeks there was an increase in carbon dioxide gas emissions, increased seismicity, and changes in Crater Lake water chemistry.
Based on information from JMA, the Tokyo VAAC reported that during 1 and 3-5 April explosions from Sakura-jima produced plumes that rose to altitudes of 1.5-4 km (5,000-13,000 ft) a.s.l. and occasionally drifted E. A video of activity from 4 April showed incandescence emanating from the crater and a few explosions that ejected incandescent material onto the flanks.
On 31 March, AVO lowered the Volcano Alert Level and the Aviation Color Code for Cleveland to Unassigned noting that no eruptive activity had been confirmed during the previous few months. Neither significant thermal anomalies nor ash deposits on snow were observed in recent satellite imagery.
Based on analyses of satellite imagery, the Darwin VAAC reported that on 4 April an ash plume from Dukono rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted 185 km E.
Based on a NOTAM, the Toulouse VAAC reported that on 3 April ash from Etna rose to an altitude between 2.4-3.4 km (8,000-11,000 ft) a.s.l. Ash was not identified in satellite imagery.
INSIVUMEH reported that during 30-31 March and 4-5 April explosions from Fuego produced ash plumes that rose 200-700 m above the crater and drifted W, SW, and S. Lava flows traveled almost 200 m SW down the Ceniza drainage and produced block avalanches from lava-flow fronts. Crater incandescence was observed at night.
INGEOMINAS reported that on 31 March and 1 April emissions from Galeras were characterized by gas-and-steam plumes with low ash content. On 1 April a M 2.3 earthquake occurred 3 km E of the crater at a depth of 6 km and was felt by nearby residents. During an overflight on 2 April scientists noted a sulfur gas odor and observed that gas emissions rose from multiple areas of the active cone.
KVERT reported moderate seismic activity at Karymsky during 25 March-1 April. Seismic data indicated that possible ash plumes rose to an altitude of 5 km (16,400 ft) a.s.l. A thermal anomaly was detected daily in satellite imagery.
Wed, 30 Mar 2011, 06:00
Based on notifications from JMA and pilot observations, the Tokyo VAAC reported that during 3-4 April ash plumes from Kirishima's Shinmoe-dake (Shinmoe peak) rose to altitudes of 4.6-6.1 km (15,000-20,000 ft) a.s.l. and drifted E.
Read allWed, 30 Mar 2011, 06:00
KVERT reported that during 25 March-1 April seismicity from Kizimen was high, with many shallow volcanic earthquakes and volcanic tremor continuing to be detected. Satellite images showed a large bright thermal anomaly daily on the volcano. Ash and gas-and-steam plumes drifted multiple directions as far as 464 km.
Read allWed, 30 Mar 2011, 06:00
Based on analyses of satellite imagery, the Tokyo VAAC reported that a possible eruption from Kliuchevskoi on 30 March produced a plume that rose to an altitude of 5.2 km (17,000 ft) a.s.l. and drifted E. Subsequent images that day showed continuing ash emissions that later dissipated.
Read allWed, 30 Mar 2011, 06:00
INSIVUMEH reported that on 28 March explosions from Santa María's Santiaguito lava dome complex produced ash plumes that rose 300-800 m above Caliente dome and drifted NNE, depositing fine ash in Quetzaltenango (10 km NNE). During 30-31 March and 4-5 April explosions produced ash plumes that rose 400-700 m above the dome and drifted S; ashfall was reported in nearby areas downwind. Avalanches descended the SW and E flanks.
Read allWed, 30 Mar 2011, 06:00
KVERT reported that during 25 March-1 April seismic data at Shiveluch indicated that possible ash plumes rose to an altitude of 3.7 km (12,100 ft) a.s.l. A thermal anomaly on the lava dome was observed in satellite imagery during 25-29 March, and ash plumes drifted 57 km SE on 26 March. Ground-based observers noted that ash-and-gas plumes rose to an altitude of 5.5 km (18,000 ft) a.s.l. during 25-30 March.
Read allWed, 30 Mar 2011, 06:00
MVO reported that during 25 March-1 April activity at the Soufrière Hills lava dome was at a low level. A swarm of 36 earthquakes occurred within an hour on 28 March, the largest volcano-tectonic swarm since February 2010. The Hazard Level remained at 3.
Read allWed, 30 Mar 2011, 06:00
CVGHM reported that during 29 March-4 April brownish-gray ash plumes from Tengger Caldera's Bromo cone rose 400-800 m above the crater and drifted N, E, and NE. Ash fell at the Bromo observation post. Incandescence emanated from the crater and incandescent material was periodically ejected above the crater.
Read allSun, 27 Mar 2011, 20:18
Lava returned to the crater floor of Pu`u O`o crater this morning, covering it with a small lava lake. The new eruptive episode marks the end of one of the longest pauses in the eruption so far. It followed a day of inflation, first at the summit, then under the eastern rift zone, indicating the rise of underground magam filling the plumbing system again.
Fri, 25 Mar 2011, 09:34
INSIVUMEH reported that during 17-18 and 20-22 March explosions from Fuego produced ash plumes that rose 300-600 m above the crater and drifted 5-8 km W, SW, and S. Incandescent material was ejected as high as 100 m above the crater. Avalanches traveled SW, into the Taniluyá, Santa Teresa, Ceniza, and Trinidad drainages.
Read allFri, 25 Mar 2011, 09:27
Elevated activity continues at Santiaguito, as recent visitors and the latest reports from INSIVUMEH confirm. The Santiaguito lava dome has been producing frequent ash explosions with plumes to 700-800 m height and small avalanches and pyroclastic flows traveling down the eastern and southern flanks of Caliente dome.
Thu, 24 Mar 2011, 17:52
According to Indonesian news, the activity at Krakatau volcano has ceased and the eruption is considered to be over. How long the repose will last, time will tell.
Wed, 23 Mar 2011, 06:00
CVGHM reported that during 21-23 March incandescent material from Karangetang was ejected 50-75 m above the crater. Lava flows traveled as far as 2 km and collapses from the lava-flow fronts generated avalanches that moved down the flanks up to 300 m further. On 24 March lava was incandescent in areas 1.5 km away from the crater.
Read allWed, 23 Mar 2011, 06:00
HVO reported that at Kilauea's east rift zone small areas of incandescence in Pu'u 'O'o crater were visible through the web camera during 23-24 March. The lava lake in the deep pit within Halema'uma'u crater was crusted over; frequent rockfalls produced a few brown-tinged plumes. On 25 March the lava lake reappeared as lava streamed across and eventually covered the floor of the pit.
Read allWed, 23 Mar 2011, 06:00
Based on analyses of satellite imagery, the Darwin VAAC reported that on 29 March an ash plume from Rabaul caldera's Tavurvur cone rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted more than 53 km NW.
Read allWed, 23 Mar 2011, 06:00
Servicio Nacional de Estudios Territoriales (SNET) reported that during a survey of the San Miguel crater on 9 and 16 March observers noted pulses of gas rising 200 m from the crater. On 12 March the number and amplitude of earthquakes increased. RSAM values rose the next day to 121 units per day on average, up from normal values around 50 units per day.
Read allWed, 23 Mar 2011, 06:00
Based on information from JMA, the Tokyo VAAC reported that during 23-26 and 29 March explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-2.4 km (4,000-8,000 ft) a.s.l. and occasionally drifted E, SE, and S. On 26 March, a pilot observed an ash plume that rose to an altitude of 3.4 km (11,000 ft) a.s.l. and drifted SE.
Read allWed, 23 Mar 2011, 06:00
Based on analyses of satellite imagery, the Darwin VAAC reported that during 25-28 March ash plumes from Bagana rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted 35-100 km NW, W, and SW.
Read allWed, 23 Mar 2011, 06:00
Based on notices from the Manila airport (RPLL), the Tokyo VAAC reported that during 25-26 March ash from Bulusan was observed. PHIVOLCS reported that cloud cover prevented ground-based observations.
Read allWed, 23 Mar 2011, 06:00
KVERT reported moderate seismic activity at Karymsky during 18-25 March. Seismic data indicated that possible ash plumes rose to an altitude of 3.5 km (11,500 ft) a.s.l. A thermal anomaly was detected in satellite imagery during 19-24 March. The Aviation Color Code remained at Orange.
Read allWed, 23 Mar 2011, 06:00
Based on notifications from JMA, the Tokyo VAAC reported that an eruption from Kirishima's Shinmoe-dake (Shinmoe peak) on 23 March produced a plume that rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted SE. Subsequent notices that day stated that the ash had dissipated.
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