Smithsonian/USGS Weekly Volcanic Activity Report 29 February – 6 March 2012 8 March 2012Posted by admin in activity reports, Alaska, Bagana, Bezymianny, Canary Islands, Chile, Cleveland, Ecuador, eruptions, Etna, Fuego, Guatemala, Hawaii, Hierro, Italy, Japan, Kamchatka, Kanaga, Karymsky, Kilauea, Kizimen, Mexico, Papua New Guinea, Popocatépetl, Puyehue, Russia, Sakura-jima, Santa María, Shiveluch, Spain, Suwanose-jima, Tungurahua, United States, Weekly Volcanic Activity Reports.
Tags: Global Volcanism Program
The latest Smithsonian Institution and United States Geological Survey Weekly Volcanic Activity Report has been published by the Global Volcanism Program, covering the week 29 February to 6 March 2012. The report is compiled by Sally Kuhn Sennert. Some of the highlights of the volcanic week:
- Continuing activity at Etna including strombolian eruptions, lava fountaining and lava flows
- Explosions at Fuego produced plumes that reached 0.6 km above the crater
- Plumes rose to 1 km above Puyehue-Cordón Caulle as low-level eruptive activity continues
Click on the map for a larger version (1211 x 784 pixels).
The Smithsonian Institution/United States Geological Survey Weekly Volcanic Activity Report for 29 February – 6 March 2012 is now available on the Global Volcanism Program website. The following is a summary and not a substitute for the full report.
- The current report: Weekly Volcanic Activity Report.
- Previous reports: Weekly Reports Archive.
- The SI/USGS map of volcanoes discussed this week.
New activity/unrest: Bezymianny (Russia), Cleveland (Alaska, USA), Etna (Italy), Kanaga (Alaska, USA), Tungurahua (Ecuador).
Ongoing activity: Bagana (Papua New Guinea), Fuego (Guatemala), Hierro (Canary Islands), Karymsky (Russia), Kilauea (Hawaii, USA), Kizimen (Russia), Popocatépetl (Mexico), Puyehue-Cordón Caulle (Chile), Sakura-jima (Japan), Santa María (Guatemala), Shiveluch (Russia), Suwanose-jima (Japan).
Note: ‘a.s.l.’ = ‘above sea level’.
Bezymianny (Russia). KVERT reported that during 24 February-2 March seismic activity at Bezymianny remained elevated, with about 7-19 weak events registered daily. A thermal anomaly was detected in satellite images. Gas-and-steam activity was observed on 26 February; clouds obscured the volcano on the other days. One short volcanic tremor episode was detected on 29 February. About 40 seismic events were detected on 1 March and, according to satellite data analysis, the size and brightness of a thermal anomaly abruptly increased on 2 March. The Aviation Colour Code was raised to Red. During 2-5 March there were 25-40 weak seismic events detected; cloud cover prevented observations of the volcano. [GVP: Bezymianny]
Cleveland (Alaska, USA). AVO reported that during 24 February-2 March satellite images of Cleveland revealed no unusual activity and no significant changes in the size of the lava dome. A weak thermal anomaly was detected in satellite imagery on 3 March. The Volcano Alert Level remained at Watch and the Aviation Colour Code remained at Orange. No current seismic information was available because Cleveland does not have a real-time seismic network. [GVP: Cleveland]
Etna (Italy). Sezione di Catania – Osservatorio Etneo reported that the third episode of lava fountaining from Etna’s New Southeast Crater (New SEC) occurred on the morning of 4 March and was more explosive than the preceding episode. The beginning of the eruption was characterized by a rapid increase in volcanic tremor amplitude coincident with Strombolian explosions that increased in intensity and frequency. Just after 0800 lava overflowed the deep breach in the SE rim of the crater and reached the SE base of the cone within 15 minutes, then advanced towards the W rim of the Valle del Bove. Explosive activity changed to continuous lava fountaining and an eruption plume developed at about 0830. Large pyroclasts fell on the steep flanks of the cone, causing avalanches. At about 0850 small pyroclastic flows generated by the partial collapse of the eruption column mainly descended the NE flank, and somewhat down the S flank. A lava flow was emitted from a new eruptive vent on the upper SW flank of the New SEC cone and descended into the saddle between the old and new SEC cones. The lava interacted with snow, causing powerful explosions and small pyroclastic flows. These phreatic explosions generated jets of vapour and launched rock fragments to distances of several tens of meters. A lahar developed which traveled toward the ‘Belvedere’ monitoring station, on the W rim of the Valle del Bove, and passed a few tens of metres to the N of the monitoring instruments. A lava flow also issued from an eruptive fissure on the upper N flank of the cone and descended a few hundred meters to the NE, surrounding the N base of the cone. After descending the steep W slope of the Valle del Bove, the flow split into several branches on the more gently sloping terrain. These branches exceeded in length those of 9 February, reaching a total distance of about 3.5 km from the crater. Shortly after 1000, the activity started to diminish; lava fountaining ceased at 1032, two hours after the onset of the paroxysmal phase. The lava flow emitted from the fissure on the SW flank of the cone continued advancing for a few hours after the cessation of the activity. The eruption column rose several kilometres above the summit of Etna. Ash and lapilli were carried NE by the wind, affecting the areas around Piedimonte, Etneo, and Taormina. Fine ash fell as far as the Messina area and southern Calabria. Again, the pyroclastic cone of the New SEC had grown in height, mainly on its N rim. [GVP: Etna]
Kanaga (Alaska, USA). AVO reported that the level of unrest at Kanaga declined to background levels. On 2 March the Volcano Alert Level was lowered to Normal and the Aviation Colour Code was lowered to Green. [GVP: Kanaga]
Tungurahua (Ecuador). IG reported that during 29 February-2 March cloud cover prevented views of Tungurahua. On 3 March seismicity increased. Clouds mostly prevented observations; during breaks in the cloud cover ash plumes were observed rising 3 km above the crater and drifting S and SW. Explosions ejected blocks that rolled down the flanks. Two of the explosions generated sounds resembling cannon shots, and vibrated windows. Ashfall was reported in Choglontus (13 km WSW), Manzano (8 km SW), Cahuají (8 km SW), and Motilones (W). On 4 March ashfall was reported in Yuibug and observers noted hot deposits from a small pyroclastic flow that occurred high in the Achupashal drainage (NW). Ash plumes observed during breaks in the cloud cover on 5 March rose 1 km and drifted W. Ash again fell in Choglontus. Clouds prevented observations on 6 March. [GVP: Tungurahua]
Bagana (Papua New Guinea). Based on analyses of satellite imagery, the Darwin VAAC reported that on 7 March an ash plume from Bagana rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted 37 km SW. [GVP: Bagana]
Fuego (Guatemala). INSIVUMEH reported that during 1-2 March explosions from Fuego produced ash plumes that rose 600 m above the crater and drifted 15 km W and SW. Ashfall was reported in Yepocapa (W), Sangre de Cristo (W), and Panimache II (SW). Some explosions produced rumbling and degassing sounds. A 300-m-long lava flow descended the SW flank and produced block avalanches that reached vegetated areas. On 4 March the number of explosions increased to about 4-5 per hour. Explosions generated ash plumes that rose 600 m above the crater and drifted 12 km SSW. Rumbling sounds were heard 7 km away. [GVP: Fuego]
Hierro (Canary Islands). Instituto Geográfico Nacional (IGN) reported that during 29 February-6 March the seismic amplitude detected by every IGN station in El Hierro remained at very low values. Neither water discoloration nor activity was observed on the sea surface over the emission area. On 5 March, the Scientific Committee stated that the submarine eruption was over, but the volcanic process that started on mid July 2011 had not finished. The Canary Islands Government lowered the Volcanic Alert Code from Red to Yellow, maintaining a maritime exclusion zone around the emission area. Thirty four seismic events were located, most of them in the central part of the island, extending offshore to the S. Depths of the hypocentres varied between 7 and 24 km, and magnitudes were 0.1-2.1 (twenty eight events were magnitudes equal to or greater than 1). One of these events was felt by residents and had a maximum intensity value of II (EMS-98). GPS data did not show persistent trends in any horizontal or vertical components. [GVP: Hierro]
Karymsky (Russia). KVERT reported that seismic activity continued at a moderate level at Karymsky during 24 February-2 March, and indicated that possible ash plumes rose to an altitude of 3.9 km (12,800 ft) a.s.l. during 23-27 February. Satellite imagery showed a thermal anomaly on the volcano on 25 February; clouds obscured views on the other days. The Aviation Colour Code remained at Orange. [GVP: Karymsky]
Kilauea (Hawaii, USA). During 29 February-6 March, HVO reported that the lava lake circulated and periodically rose and fell in the deep pit within Kilauea’s Halema’uma’u Crater. Web camera views and satellite images indicated that lava flows continued to advance, reaching more than 7.5 km SE of Pu’u ‘O’o. Active flows were also visible at the top of the pali SE of Pu’u ‘O’o. Incandescence was visible on the NE and SE edges of the Pu’u ‘O’o crater floor and on the upper part of the lava-tube system on the E flank. According to a news article, the last house in the Royal Gardens subdivision was destroyed by a lava flow on 2 March. [GVP: Kilauea]
Kizimen (Russia). KVERT reported moderate seismic activity at Kizimen during 24 February-2 March and a large thermal anomaly that was detected in satellite images on most days. Video and satellite observations indicated both continued effusion of a large lava flow on the E flank and hot avalanches. Video data also showed strong gas-and-steam activity. The Aviation Colour Code remained at Orange. [GVP: Kizimen]
Popocatépetl (Mexico). CENAPRED reported that during 1-6 March steam-and-gas emissions rose from Popocatépetl. Emissions contained small amounts of ash on 1 March and crater incandescence was observed at night. During the night on 2 March crater incandescence rose 200-300 m above the crater. [GVP: Popocatépetl]
Puyehue-Cordón Caulle (Chile). Based on seismicity detected during 28 February-4 March, OVDAS-SERNAGEOMIN reported that the eruption from the Cordón Caulle rift zone, part of the Puyehue-Cordón Caulle volcanic complex, continued at a low level. During 28-29 February plumes observed with a web camera and satellite images rose 1 km above the crater and drifted 40 km NNE. During 2-3 March plumes rose 0.7-3 km above the crater and drifted SE. Cloud cover prevented observations of the crater on 4 March. The Alert Level remained at Red. [GVP: Puyehue-Cordón Caulle]
Sakura-jima (Japan). Based on information from JMA, the Tokyo VAAC reported that during 29 February-7 March explosions from Sakura-jima often produced plumes that rose to altitudes of 1.2-3 km (4,000-10,000 ft) a.s.l. and drifted NW, E, and SE. A pilot observed an ash plume on 5 March. Another pilot report on 6 March noted a plume drifting SE at an altitude of 2.4 km (8,000 ft) a.s.l. [GVP: Sakura-jima]
Santa María (Guatemala). INSIVUMEH reported that during 1-2 March explosions from Santa María’s Santiaguito lava-dome complex generated ash plumes that rose 800 m above the crater and drifted 20 km W and SW. Block avalanches descended the SW flank, and lava flows were active on the S, SW, and NE flanks. Based on analyses of satellite imagery, the Washington VAAC reported that during 3-4 March ash plumes drifted SW. On 5 March an ash plume rose to an altitude of 4.6 km (15,000 ft) a.s.l. [GVP: Santa María]
Shiveluch (Russia). KVERT reported that seismic activity at Shiveluch was low during 23 February-2 March. Ground-based observers and satellite imagery indicated that a viscous lava flow continued to effuse in the crater formed during a 2010 eruption. Seismic activity increased on 28 February and hot avalanches likely occurred at the lava dome. Satellite imagery showed a weak thermal anomaly over the lava dome during 23-26 February. Moderate fumarolic activity at the lava dome was observed during 1-2 March; cloud cover prevented observations on the other days. The Aviation Colour Code remained at Orange. [GVP: Shiveluch]
The foregoing is a summary of the Smithsonian Institution/United States Geological Survey Weekly Volcanic Activity Report covering 29 February – 6 March 2012. It is provided for information only, and is based on but not a substitute for the full report, which comes with its own criteria and disclaimers. The map base is derived from the Smithsonian Institution/USGS/US Naval Research Laboratory This Dynamic Planet website.
For all our coverage of the SI/USGS Weekly Volcanic Activity Reports: Weekly Volcanic Activity Reports « The Volcanism Blog.