Based on information from JMA, the Tokyo VAAC reported that an eruption occurred at Suwanose-jima on 30 November at 1607. The eruption produced a plume to a height of ~1.2 km.
During 24-30 November, growth of the new lava dome inside the crater of St. Helens continued and was accompanied by intermittent emissions of steam and ash. Overall seismicity remained at low levels compared to that observed early in this unrest, consistent with a continuing, slow rise of magma driving uplift of the crater floor and feeding the extrusion of lava onto the surface, where it builds a dome.
During 19-26 November, the seismic network at Soufrière Hills recorded 25 hybrid earthquakes, five volcano-tectonic earthquakes, three rockfalls, and one long-period earthquake. The sulfur-dioxide flux was between 125 and 330 metric tons per day, averaging 195 metric tons per day during the report period.
During 24-26 November, weak-to-moderate explosions occurred at Santa María's Santiaguito lava-dome complex, producing plumes to a maximum height of 1.3 km above the crater. Block-lava avalanches traveled down the SW flank of Caliente Dome.
The Goma Volcano Observatory reported that during 10-17 November continuous volcanic tremor was recorded at all seismic stations located around Nyiragongo. Visual observation of the volcano's summit on 12 and 13 November revealed that the lava lake surface had widened considerably, with strong lava fountains. Numerous Pele's hairs and scoriae were seen on the cone's S, W, and N sides.
Around 26 November, the Concern Color Code at Kluichevskoi was reduced from Yellow to Green, the lowest level. During 19-26 November, seismicity was at background levels. Gas-and-steam plumes were seen up to 5 km a.s.l. on 24 November and weak fumarolic activity was observed on several days.
Surface lava flows at Kilauea were visible along two to three arms of the PKK lava flow on the Pulama pali fault scarp during 24-30 November. Most vents in the crater of Pu`u `O`o were incandescent. Lava entered the ocean through 26 November.
During 24-26 November there were several explosions at Fuego. On 25 and 26 November ash plumes from these explosions rose to low levels above the volcano. Incandescent lava was hurled ~100 m above the volcano and avalanches of block lava traveled towards the Taniluyá and Ceniza ravines.
Wed, 24 Nov 2004, 06:00
During 26-30 November, several small explosions occurred at Colima. Based on information from the Mexico City MWO, the Washington VAAC reported that a steam-and-ash emission occurred on 25 November. Satellite imagery showed the plume at a height of ~6 km a.s.l.
Read allWed, 17 Nov 2004, 06:00
Volcanic and seismic activity at Tungurahua during the report period were at relatively low levels, characterized by several long-period earthquakes and small to moderate explosions. Emissions mainly consisted of steam, gas, and small amounts of ash. During 17-18 November, explosions generated steam columns that rose 300-500 m above the summit of the volcano and drifted SSW.
Read allWed, 17 Nov 2004, 06:00
During 17-23 November, the Darwin VAAC issued numerous volcanic ash advisories concerning plumes emitted from Manam that were visible on satellite imagery. On 19 November at 1125, a plume visible on satellite imagery reached a height of 7-8 km a.s.l and extended 74 km to the NE. A plume detected on 23 November at 2225 rose to around 14 km a.s.l and extended 130 km to the ESE.
Read allWed, 17 Nov 2004, 06:00
Galeras volcano erupted explosively on 21 November at 1544, Instituto Colombiano de Geología y Minería reported. The eruption produced a shock wave felt as far away as Cimarrones (18 km N of the volcano), Chachagui (17 km N of the volcano), and Laguna de La Cocha (20 km SW of the volcano). Effects of the shock wave varied from a loud roar, to the vibration of large windows, to the feeling of an earthquake.
Read allWed, 17 Nov 2004, 06:00
Growth of the new lava dome inside the crater of St. Helens continued and was accompanied by intermittent emissions of steam and ash. When weather permitted during the report period, a plume was observed rising passively and drifting out of the crater.
Read allWed, 17 Nov 2004, 06:00
Elevated levels of seismicity continued to be recorded at Mount Spurr. Seismicity rates have been relatively constant in the last week at roughly 5 locatable earthquakes per day. No unusual activity was observed in satellite or web camera images. Spurr remained at Concern Color Code Yellow.
Read allWed, 17 Nov 2004, 06:00
Seismicity was above background levels at Shiveluch during 12-19 November, with weak shallow earthquakes occurring at a depth of 0.5 km beneath the active lava dome. Based on interpretations of seismic data, possible ash-and-gas explosions up to 6 km a.s.l were registered on 15 November. Ash-and-gas explosions up to 4-5 km a.s.l were noted all week and possible weak ash-and-gas explosions and hot avalanches also occurred.
Read allWed, 17 Nov 2004, 06:00
During 17-22 November, weak-to-moderate explosions occurred at Santa María's Santiaguito lava-dome complex, causing the emission of ash columns to heights of 300-1000 m above the active crater. Slight amounts of light gray ash fell on the flanks of the volcano.
Read allWed, 17 Nov 2004, 06:00
IGNS reported that a new heating cycle may be under way at Ruapehu volcano. The temperature of Crater Lake has increased three degrees to 18 degrees Celsius, and elevated levels of volcanic tremor have occurred over the last three weeks. Ruapehu remained at Volcanic Alert Level 1 (some signs of volcano unrest).
Read allWed, 17 Nov 2004, 06:00
The Toulouse VAAC reported that an eruption began at Nyiragongo sometime earlier than 0700 on 22 November. A narrow SW-drifting plume was discernable on satellite imagery at a height of around 5 km a.s.l. A narrow plume was visible again on satellite imagery on 23 November at 1130, although no ash was identifiable.
Read allWed, 17 Nov 2004, 06:00
Lava from Kilauea's PKK flow continued to enter the sea at the newly formed lava delta at eastern Lae`apuki delta during 17-23 November. Fieldwork on 18 November determined that the new lava delta is 260 m long and extends about 80 m beyond pre-existing land (the front of the old Lae`apuki delta). The area of the delta is about 1.2 ha.
Read allWed, 17 Nov 2004, 06:00
During the report period, avalanches of incandescent volcanic material continued towards the Lajas and Taniluyá ravines on the volcano's SE and SW flanks. Small and moderate explosions expelled abundant incandescent lava to heights ~150 m above the crater. Some explosions generated rumblings, shock waves, and fine ash that was deposited on the skirts of the volcano.
Read allWed, 17 Nov 2004, 06:00
During 16-22 November, block-lava flows continued to travel down Colima's N, W, NW, and S flanks as they have since 30 September. The lava flow on the N flank is 2200 m long and approximately 330 m wide. The lava flow advancing on the NW flank is at least 600 m long by 200 m at its widest part.
Read allWed, 10 Nov 2004, 06:00
Volcanic and seismic activity at Tungurahua during the report period were at relatively low levels, characterized by several long-period earthquakes and small to moderate explosions. Emissions mainly consisted of steam, gas, and small amounts of ash. On 15 November, incandescence was observed in the crater of the volcano and explosions generated steam columns with moderate ash content that rose ~2 km above the crater and drifted S.
Read allWed, 10 Nov 2004, 06:00
Rabaul Volcanological Observatory reported a Strombolian eruption at Manam volcano that began 10 November at 2200 and lasted until 11 November at 1915. There was some fluctuation in intensity during the course of the eruption. The ash column from the eruption was estimated to have risen ~5-6 km above the crater, and perhaps rose as high as ~9 km above the crater at around 1732 according to an Air Niugini pilot account.
Read allWed, 10 Nov 2004, 06:00
According to news reports, Asama volcano erupted with a loud explosion 14 November at 2059. The Japan Meteorological Agency rated the eruption as mid-sized, 3 on a scale of 5 in terms of power of the explosion. The agency issued a warning of falling ash in areas downwind of the volcano, although no ash plume was observed due to cloudy weather conditions.
Read allWed, 10 Nov 2004, 06:00
Growth of the new lava dome inside the crater of St. Helens continued and was accompanied by intermittent emissions of steam and ash. When weather permitted during the report period, a plume was observed rising passively and drifting out of the crater.
Read allWed, 10 Nov 2004, 06:00
Elevated levels of seismicity continued to be recorded at Spurr during 5-12 November. A period of slightly increased seismicity occurred between 6-8 November when as many as three shallow earthquakes per hour were recorded. Since then, the level of seismicity had declined to an average of six earthquakes per day.
Read allWed, 10 Nov 2004, 06:00
During 8-15 November, volcanic and seismic activity at Soufrière Hills remained elevated. The seismic network recorded one rockfall and nine hybrid earthquakes. Weather conditions limited measurements of sulfur dioxide emissions during 8-15 November.
Read allWed, 10 Nov 2004, 06:00
Seismicity was above background levels at Shiveluch during 5-12 November, with weak shallow earthquakes occurring beneath the active lava dome. Based on interpretations of seismic data, possible ash-and-gas explosions up to 6.5-7 km a.s.l. were registered on 5, 7, 9, and 11 November.
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