Smithsonian/USGS Weekly Volcanic Activity Report 7-13 March 2012

The latest Smithsonian Institution and United States Geological Survey Weekly Volcanic Activity Report has been published by the Global Volcanism Program, covering the week 7-13 March 2012. The report is compiled by Sally Kuhn Sennert. Some of the news from a week that has seen quite a lot of new activity:

• An explosive eruption at Bezymianny sent ash up to 8 km altitude
• Activity at Nevado del Ruiz marked by explosions, ash emissions and increased seismicity
• Cleveland stirs with small explosive eruptions
• Explosions at Santa María produce localized ashfall

Click on the map for a larger version (1211 x 784 pixels).

The Smithsonian Institution/United States Geological Survey Weekly Volcanic Activity Report for 7-13 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), Ijen (Indonesia), Iliamna (Alaska, USA), Lamongan (Indonesia), Marapi (Indonesia), Nevado del Ruiz (Colombia), Tungurahua (Ecuador).

Ongoing activity: Karymsky (Russia), Kilauea (Hawaii, USA), Kizimen (Russia), Puyehue-Cordón Caulle (Chile), Sakura-jima (Japan), Santa María (Guatemala), Shiveluch (Russia), Villarrica (Chile).

Note: ‘a.s.l.’ = ‘above sea level’.

NEW ACTIVITY/UNREST

Bezymianny (Russia). KVERT reported that a strong explosive eruption from Bezymianny was detected by seismic instruments on 9 March. Ash plumes rose to altitudes of 3.5-5 km (11,500-16,400 ft) a.s.l. and drifted NE. During the most intense phase of the eruption ash plumes from pyroclastic flows rose to an altitude of 8 km (26,200 ft) a.s.l. Satellite imagery showed the plume drifting 700 km NE. Ashfall was reported in Ust-Kamchatsk Village (120 km ENE). Later that day activity decreased significantly and the Aviation Colour Code was lowered to Orange. During 9-13 March strong gas-and-steam emissions were noted, a viscous lava flow effused onto the lava-dome flank, and a thermal anomaly continued to be detected in satellite imagery. The Aviation Colour Code was lowered to Orange on 14 March. [GVP: Bezymianny]

Cleveland (Alaska, USA). AVO reported that a small explosion from Cleveland was detected at 1905 on 7 March by distant seismic stations and infrasound arrays. Weather conditions prevented the detection of a possible eruption cloud in satellite images or by visual observation of the summit. Another small explosion was detected at 1605 on 9 March and again weather conditions prevented observations. No other activity was detected during 11-13 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]

Ijen (Indonesia). CVGHM raised the Alert Level for Ijen from 2 to 3 (on a scale of 1-4) on 12 March because of increased seismicity and visual observations. On 10 March scientists observed some plant damage around the crater lake and a 10-m-wide area of disrupted water on the crater-lake surface. [GVP: Ijen]

Iliamna (Alaska, USA). AVO reported that earthquake activity had steadily increased at Iliamna during the past three months. On 9 March AVO increased the Alert Level to Advisory and the Aviation Colour Code to Yellow. The report noted that the current activity was characterized by numerous earthquakes that had varied in their number and magnitude over the past week. [GVP: Iliamna]

Lamongan (Indonesia). CVGHM reported that during 1 February-9 March diffuse white plumes rose at most 20 m above Lamongan. Seismicity increased on 23 February, then fluctuated in intensity through 7 March. Seismicity increased significantly on 8 March and tremor was recorded continuously the next day. CVGHM raised the Alert Level to 2 (on a scale of 1-4) on 9 March. Residents and tourists were prohibited from going within a 1-km-radius of the active crater. [GVP: Lamongan]

Marapi (Indonesia). According to a news article from 5 March, several eruptions from Marapi produced ash plumes during the previous week. An ash plume rose 1 km above the crater on 4 March and drifted 10 km S. A representative from CVGHM noted that the Alert Level remained at 2 (on a scale of 1-4). [GVP: Marapi]

Nevado del Ruiz (Colombia). INGEOMINAS reported a significant increase in seismicity at Nevado del Ruiz during 5-11 March. On 8 March scientists aboard an overflight observed a gas plume that rose 1.4 km above Arenas crater, originating from multiple emission sources and thermally anomalous areas within the crater. They noted ash deposits on the glacier, near the crater rim and on the E flank, likely from an explosion on 22 February. Later that day a small explosion detected by the seismic network produced an ash emission that was observed with a camera installed in La Piranha (NW). Increased sulphur dioxide emissions were also detected. Fieldwork revealed ash deposits at the headwaters of Gualí River, SW of Arenas crater. [GVP: Nevado del Ruiz]

Tungurahua (Ecuador). IG reported that, although visual observations of Tungurahua during 6-11 March were sometimes limited due to cloud cover, steam plumes were noted on 6 and 8 March, and a gas-and-ash plume that rose 500 m above the crater was observed on 7 March. Slight ashfall was reported in Choglontus (13 km WSW) on 7 March. An ash plume rose 1 km above the crater on 11 March and drifted SE. Lahars descended the Chacauco (NW) and Mapayacu (SW) drainages. The next day seismicity increased and an ash plume rose 2-3 km above the crater that drifted W and SW. During 12-13 March ashfall was reported in Choglontus and Manzano (8 km SW). [GVP: Tungurahua]

ONGOING ACTIVITY

Karymsky (Russia). KVERT reported that during 2-9 March seismic activity from Karymsky continued to be detected and indicated that possible ash plumes rose to an altitude of 3.4 km (11,000 ft) a.s.l. on 3 March. Satellite imagery showed a thermal anomaly on the volcano on 2 March. The Aviation Colour Code remained at Orange. [GVP: Karymsky]

Kilauea (Hawaii, USA). During 7-13 March, HVO reported that the lava lake periodically rose and fell in the deep pit within Kilauea’s Halema’uma’u Crater. Almost daily measurements indicated that the gas plume from the vent continued to deposit variable amounts of ash and fresh spatter nearby. Incandescence was visible from both a small pit on the NE edge and a small spatter cone on the SE edge of the Pu’u ‘O’o crater floor, and on the upper part of the lava-tube system on the E flank. Lava flows continued to advance down the pali and across the coastal plain. On 12 March the leading edge of the flows were 9 km SE of Pu’u ‘O’o and about 2 km from the coast. [GVP: Kilauea]

Kizimen (Russia). KVERT reported moderate seismic activity at Kizimen during 2-9 March and a large thermal anomaly that was detected in satellite images. Video and satellite observations indicated both continued effusion of a large lava flow on the E flank and hot avalanches. The Aviation Colour Code remained at Orange. [GVP: Kizimen]

Puyehue-Cordón Caulle (Chile). Based on seismicity detected during 6-13 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. Plumes observed most days in web camera and satellite images rose 0.3-1.2 km above the crater and drifted 30-50 km NNE, E, and SW. Incandescence from the crater was observed during 5-8 and 10-13 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 7-9 and 11-13 March explosions from Sakura-jima often produced plumes that rose to altitudes of 1.2-2.7 km (4,000-9,000 ft) a.s.l. and drifted E and SE. Pilots observed ash plumes during 9 and 11-13 March that rose to altitudes of 1.8-3 km (6,000-10,000 ft) a.s.l. [GVP: Sakura-jima]

Santa María (Guatemala). INSIVUMEH reported that during 8-9 March explosions from Santa María’s Santiaguito lava-dome complex generated ash plumes that rose 800-1,000 m above the crater and drifted W and SW. Block avalanches descended the SE and NW flanks. Ashfall was reported in the communities of Loma Linda, San Marcos, and Palajunoj. During 11-12 March explosions generated ash plumes that rose 800 m above the crater and drifted 20 km SSW. Ashfall was reported at the observatory, on the El Faro and Patzulin ranches, and in the village of Las Marías. Lava flows continued to produce avalanches. [GVP: Santa María]

Shiveluch (Russia). KVERT reported that seismic activity at Shiveluch was low during 2-9 March. Ground-based observers and satellite imagery indicated that a viscous lava flow continued to effuse in the crater formed during a 2010 eruption. Moderate fumarolic activity at the lava dome was observed during 2 and 5-8 March; cloud cover prevented observations on the other days. Satellite imagery showed a weak thermal anomaly over the lava dome during 3, 5, and 7-8 March. The Aviation Colour Code remained at Orange. Based on information from KVERT, the Tokyo VAAC reported that on 10 March an ash plume rose to an altitude of 5.2 km (17,000 ft) a.s.l. and drifted NE. Yelizovo Airport (UHPP) reported that an ash plume rose to an altitude of 2.1 km (7,000 ft) a.s.l. and drifted SW. [GVP: Shiveluch]

Villarrica (Chile). According to Projecto Observación Visual Volcán Villarrica (POVI), two small ash emissions from Villarrica occurred on 7 March. Incandescence from the crater was observed from the town of Pucon (16 km N) during 7-8 March. [GVP: Villarrica]

The foregoing is a summary of the Smithsonian Institution/United States Geological Survey Weekly Volcanic Activity Report covering 7-13 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.