Activity for the week of 28 March-3 April 2007
The Weekly Volcanic Activity Report is a cooperative project between the Smithsonian's Global Volcanism Program and the US Geological Survey's Volcano Hazards Program. Updated by 2300 UTC every Wednesday, notices of volcanic activity posted on these pages are preliminary and subject to change as events are studied in more detail. This is not a comprehensive list of all of Earth's volcanoes erupting during the week, but rather a summary of activity at volcanoes that meet criteria discussed in detail in the "Criteria and Disclaimers" section. Carefully reviewed, detailed reports on various volcanoes are published monthly in the Bulletin of the Global Volcanism Network.
New Activity / Unrest
| 16.25°S, 168.12°E
| Elevation 1334 m
The Wellington VAAC reported that on 3 April pilots observed lava and ash emissions from Ambrym. Ash plumes rose to altitudes below 2.4 km (8,000 ft) a.s.l.
Source: Wellington Volcanic Ash Advisory Center (VAAC)
| Komba Island (Indonesia)
| 7.791°S, 123.585°E
| Elevation 633 m
Based on satellite imagery and CVGHM, the Darwin VAAC reported that during 29 March-3 April semi-continuous emissions from Batu Tara produced diffuse plumes. The plumes rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted E and N.
Source: Darwin Volcanic Ash Advisory Centre (VAAC)
| 0.077°S, 77.656°W
| Elevation 3562 m
On 28 March, observers reported roaring noises and an ash column from Reventador that rose to an altitude of 5.6 km (18,400 ft) a.s.l. and drifted W. A small lava flow traveled 200 m down the S flank. Incandescent material and ash emissions were observed during 29-31 March. On 1 April, ash plumes rose to an altitude of 7.6 km (24,900 ft) a.s.l. and incandescent rocks were ejected about 50 m above the crater. Incandescent material was again seen at the summit on 2 April. The Washington VAAC reported that a strong hotspot was present on satellite imagery during 1-3 April. Based on pilot reports, IG reported that a steam-and-gas plume with little ash content rose to an altitude of 6.1 km (20,000 ft) a.s.l. and drifted W on 3 April.
Sources: Instituto Geofísico-Escuela Politécnica Nacional (IG), Washington Volcanic Ash Advisory Center (VAAC)
| Central Java (Indonesia)
| 7.242°S, 109.208°E
| Elevation 3428 m
According to a news article, a volcano observer monitoring Slamet reported on 1 April that plume activity had increased in intensity and frequency over the previous two weeks. Plumes rose to an estimated altitude of 3.8 km (12,500 ft) a.s.l.
Source: Earth Times
| 1.467°S, 78.442°W
| Elevation 5023 m
IG reported that on 27 March, at 1716, an ash column from Tungurahua rose to an altitude of 11 km (36,000 ft) a.s.l. An accompanying pyroclastic flow traveled 1 km down the Mandur gorge on the NW flank. A lahar traveled W down the Bilbao gorge and vibrated near-by structures. On 28 March, ash plumes again rose to altitudes of 11 km (36,000 ft) a.s.l. Ashfall was reported from areas downwind. Noises that resembled rolling blocks down the flanks were reported. Hot steaming mudflows traveled N, NW, and W. On 29 March, three explosions rattled windows in areas as far away as 8 km. During 30 March-3 April, ash plumes, occasionally accompanied by roaring noises and "cannon shots," rose to altitudes of 6-10.5 km (19,700-34,400 ft) a.s.l. and drifted mainly W and NW. Incandescent material was ejected 300 m above the crater and subsequently descended about 1 m down the flank on 31 March; similar activity was observed at the summit during 1-2 April. Ashfall was reported from areas about 8 km SW, N, and W.
Source: Instituto Geofísico-Escuela Politécnica Nacional (IG)
| Siau Island (Indonesia)
| 2.781°N, 125.407°E
| Elevation 1797 m
According to a news article, eruption plumes from Karangetang rose to an altitude of 1.9 km (6,000 ft) a.s.l. on 27 March. Pyroclastic flows may have occurred the next day.
Source: The Jakarta Post
| Eastern Kamchatka (Russia)
| 54.049°N, 159.443°E
| Elevation 1513 m
Based on satellite imagery and information from the Petropavlovsk-Kamchatsky Flight Information Region (FIR), the Tokyo VAAC reported that an eruption plume from Karymsky rose to an altitude of 3 km (10,000 ft) a.s.l. on 31 March.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
| Hawaiian Islands (USA)
| 19.421°N, 155.287°W
| Elevation 1222 m
During 28 March-3 April, lava from Kilauea continued to flow across a lava delta into the ocean at the Kamokuna entry. Lava was not seen entering the ocean at the East Lae'apuki entry. During 28-29 March, a more than usual number of earthquakes were located near the Halema'uma'u and Koko'olau craters and on the S flank. Incandescence was intermittently visible from several breakouts on the Pulama pali and from several vents in Pu'u 'O'o's crater. On 31 March, a major lava breakout from the Campout flow caused trees to ignite on a near-by kipuka (an "island" of vegetation) and produced small explosions from trapped gas.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
| Central Kamchatka (Russia)
| 56.056°N, 160.642°E
| Elevation 4754 m
Based on observation and video data, lava from Kliuchevskoi flowed down the NW flank on 29 March. On 31 March, lava bombs from Strombolian activity were projected about 100-200 m above the crater. According to a news article, lava flows are interacting with snow and ice and producing vapor plumes.
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT), RIA Novosti
Piton de la Fournaise
| Reunion Island (France)
| 21.244°S, 55.708°E
| Elevation 2632 m
OVPDLF reported that on 2 April lava fountains about 50 m high erupted from a fissure at Piton de la Fournaise. The NW-SE-trending fissure was located SW of Dolomieu crater and was about 1 km long.
Source: Observatoire Volcanologique du Piton de la Fournaise (OVPF)
| 19.023°N, 98.622°W
| Elevation 5393 m
Based on information from the Mexico City MWO, the Washington VAAC reported that an ash plume from Popocatépetl rose to an altitude of 7.6 km (25,000 ft) a.s.l. and drifted NE on 1 April.
Source: Washington Volcanic Ash Advisory Center (VAAC)
| New Britain (Papua New Guinea)
| 4.271°S, 152.203°E
| Elevation 688 m
RVO reported that during 26 March-1 April, Rabaul caldera's Tavurvur cone emitted steam and steam-and-ash plumes that rose to 0.8 km (2,600 ft) a.s.l. and drifted E, N, and NW. Roaring noises occasionally accompanied emissions. Incandescent material was ejected to at most 100 m above the lowest part of the vent during 26-30 March. Based on reports from RVO and satellite imagery, the Darwin VAAC reported that ash plumes rose to altitudes of 1.5-3 km (5,000-10,000 ft) a.s.l. and drifted NE during 1-2 April.
Sources: Rabaul Volcano Observatory (RVO), Darwin Volcanic Ash Advisory Centre (VAAC)
| 14.757°N, 91.552°W
| Elevation 3745 m
INSIVUMEH reported that explosions from Santa María's Santiaguito lava dome complex produced ash plumes that rose to an altitude of 5 km (16,400 ft) a.s.l. on 29 March. Ashfall was reported near the Observatory Vulcanológico de Santiaguito (OVSAN), about 5 km S. On 30 March, the Washington VAAC reported that diffuse ash plumes were visible on satellite imagery drifting SW. On 2 April, INSIVUMEH reported that ash plumes rose to 4.4 km (14,400 ft) a.s.l. and drifted SW.
Sources: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH), Washington Volcanic Ash Advisory Center (VAAC)
| Central Kamchatka (Russia)
| 56.653°N, 161.36°E
| Elevation 3283 m
An explosive event at Shiveluch on 29 March produced an ash plume that rose to an estimated altitude of 9.8 km (32,000 ft) a.s.l. and drifted NE. Based on reports from the Yelizovo Meteorological Watch Office and satellite imagery, the Tokyo VAAC reported that the plume reached an altitude of 11.9 km (39,000 ft) a.s.l. The next day, an explosive event that lasted about 6 minutes produced a plume to altitudes of 10.1-12.2 km (33,000-40,000 ft) a.s.l., based on estimates from AVO, Tokyo VAAC, and the Kamchatkan Branch of Geophysical Services. The plume drifted NE.
According to a news article, a mudflow covered an approximately 900-m-long section of road, about 20 km from Shiveluch on 31 March.
Sources: US Geological Survey Alaska Volcano Observatory (AVO), Itar-Tass News
| 16.72°N, 62.18°W
| Elevation 915 m
During 23 March-3 April, lava-dome growth at Soufrière Hills was reduced or possibly paused. Small, intermittent pyroclastic flows occurred in the Tar River Valley. Fumarolic activity was observed around the region of a collapse scar at the head of Tyres Ghaut and was audible during 28-29 March. The Washington VAAC reported that a SW-drifting, diffuse plume and a hotspot were visible on satellite imagery on 2 April.
Source: Montserrat Volcano Observatory (MVO)
| United States
| 46.2°N, 122.18°W
| Elevation 2549 m
Data from deformation-monitoring instruments and observations from a remote camera showed that during 28 March-3 April, lava-dome growth at Mount St. Helens continued. Seismicity persisted at low levels, punctuated by M 1.5-2.5 and occasionally larger earthquakes. On 3 April, a GPS unit on an active spine showed W-ward movement at a rate of about 30 cm/day.
Source: US Geological Survey Cascades Volcano Observatory (CVO)
| Ryukyu Islands (Japan)
| 29.638°N, 129.714°E
| Elevation 796 m
Based on information from JMA, the Tokyo VAAC reported explosions from Suwanose-jima on 30 March and 2 April. Ash was not visible on satellite imagery.
Source: Tokyo Volcanic Ash Advisory Center (VAAC)
| 16.355°S, 70.903°W
| Elevation 5672 m
Based on pilot reports, the Buenos Aires VAAC reported that an ash cloud from Ubinas rose to 5.5-6.1 km (18,000-20,000 ft) a.s.l. on 30 March and drifted E. According to a news article, local residents observed rockfalls and reported ashfall. A scientist from the Geological, Mining, and Metallurgic Institute (INGEMMET) reported that the eruption was the largest in a two-week period characterized by an increased rate of explosions. A diffuse ash plume was visible on satellite imagery on 3 April drifting NE.
Sources: Buenos Aires Volcanic Ash Advisory Center (VAAC), Living in Peru
Criteria & Disclaimers
The Weekly Volcanic Activity Report does not necessarily include all volcanic activity that occurred on Earth during the week. More than a dozen volcanoes globally have displayed more-or-less continuous eruptive activity for decades or longer, and such routine activity is typically not reported here. Moreover, Earth's sea-floor volcanism is seldom reported even though in theory it represents the single most prolific source of erupted material. The Weekly Volcanic Activity Report summarizes volcanic activity that meets one or more of the following criteria:
- A volcano observatory raises or lowers the alert level at the volcano.
- A volcanic ash advisory has been released by a volcanic ash advisory center (VAAC) stating that an ash cloud has been produced from the volcano.
- A verifiable news report of new activity or a change in activity at the volcano has been issued.
- Observers have reported a significant change in volcanic activity. Such activity can include, but is not restricted to, pyroclastic flows, lahars, lava flows, dome collapse, or increased unrest.
Volcanoes are included in the "New Activity/Unrest" section of the Weekly Volcanic Activity Report if the activity occurs after at least 3 months of quiescence. Once a volcano is included in the "New Activity/Unrest" section, updates will remain in that section unless the activity continues for more than 1 month without escalating, after which time updates will be listed in the "Continuing Activity" section. Volcanoes are also included in the "New Activity/Unrest" section if the volcano is undergoing a period of relatively high unrest, or increasing unrest. This is commonly equal to Alert Level Orange on a scale of Green, Yellow, Orange, Red, where Red is the highest alert. Or alert level 3 on a scale of 1-4 or 1-5.
It is important to note that volcanic activity meeting one or more of these criteria may occur during the week, but may not be included in the Weekly Volcanic Activity Report because we did not receive a report.
1. The Weekly Volcanic Activity Report is intended to provide timely information about global volcanism on a weekly basis. Consequently, the report is generated rapidly by summarizing volcanic reports from various sources, with little time for fact checking. The accuracy of the Weekly Volcanic Activity Report is dependent upon the quality of the volcanic activity reports we receive. Reports published in the Bulletin of the Global Volcanism Network are monthly, and more carefully reviewed, although all of the volcanoes discussed in the Weekly Volcanic Activity Report are not necessarily reported in the Bulletin. Because of our emphasis on rapid reporting on the web we have avoided diacritical marks. Reports are updated on the Weekly Volcanic Activity Report web page as they are received, therefore information may be included regarding events that occurred before the current report period.
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3. Preliminary accounts sometimes contain exaggerations and "false alarms," and accordingly, this report may include some events ultimately found to be erroneous or misleading.
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