REPORT OF ACTIVE VOLCANOES 9 March-15 March 2011
New Activity/Unrest: | Karangetang [Api Siau], Siau I | Kilauea, Hawaii (USA) | Kirishima, Kyushu | Santa María, GuatemalaOngoing Activity: | Dukono, Halmahera | Karymsky, Eastern Kamchatka (Russia) | Kizimen, Eastern Kamchatka (Russia) | Nyiragongo, Democratic Republic of Congo | Popocatépetl, México | Sakura-jima, Kyushu | Shiveluch, Central Kamchatka (Russia) | Suwanose-jima, Ryukyu Islands (Japan)
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.
Note: Many news agencies do not archive the articles they post on the Internet, and therefore the links to some sources may not be active. To obtain information about the cited articles that are no longer available on the Internet contact the source.
New Activity/Unrest
KARANGETANG [API SIAU] Siau I 2.78°N, 125.40°E; summit elev. 1784 m
Based on analyses of satellite imagery, the Darwin VAAC reported that on 11 March an ash plume from Karangetang rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted 55 km SW. According to news reports, lava flows at the summit were visible on 11 March. Blocks originating from the lava dome traveled as far as 2 km down the flanks. Hot gas clouds also descended the flanks. The VAAC also noted that on 13 March an ash plume rose to an altitude of 3.7 km (12,000 ft) a.s.l. and drifted 37 km.
Geologic Summary. Karangetang (also known as Api Siau) lies at the northern end of the island of Siau, N of Sulawesi, and contains five summit craters strung along a N-S line. One of Indonesia's most active volcanoes, Karangetang has had more than 40 recorded eruptions since 1675. Twentieth-century eruptions have included frequent explosions, sometimes accompanied by pyroclastic flows and lahars.
Map
Sources: Darwin Volcanic Ash Advisory Centre (VAAC), Okezone, Novinite
Karangetang [Api Siau] Information from the Global Volcanism Program
KILAUEA Hawaii (USA) 19.421°N, 155.287°W; summit elev. 1222 m
HVO reported that on 9 March vigorous spattering as high as 50 m was noted from the W end of the Kamoamoa fissure, which had opened on 5 March, along Kilauea's east rift zone between Napau Crater and Pu'u 'O'o. Low lava fountains fed a channelized 'a'a lava flow, 80-290 m wide, that advanced at least 2.9 km to the SE. The lava flow waned starting at 1700 and spattering from the fissure stopped around 2230. The Volcano Alert Level was lowered to Watch and the Aviation Color Code remained at Orange.
During 9-10 March gas measurements showed a sulfur dioxide emission rate of about 4,400 tonnes/day from all east rift zone sources. The rate dropped to 350 tonnes/day on 10 March, and to 100 tonnes/day on 13 March, a value lower than those measured for the months before the Kamoamoa fissure eruption. Seismic tremor declined, but remained elevated above pre-Kamoamoa eruption levels at the summit and the eruption site. During 13-15 March incandescent areas were visible within Pu'u 'O'o crater.
At the summit caldera, a gas plume from the deep pit within Halema'uma'u crater drifted mainly SW during 9-15 March. The level of the lava in the pit was about 220 m below the crater floor, confirmed during an overflight on 9 March. It could not be observed during an overflight the next day because the bottom of the vent was obscured by rubble. Incandescence was occasionally seen in the web camera. An overflight on 14 March revealed that lava was present in the vent; the level slowly rose during the night. On 15 March tephra and fresh spatter was collected from an area beneath the plume.
Geologic Summary. Kilauea, one of five coalescing volcanoes that comprise the island of Hawaii, is one of the world's most active volcanoes. Eruptions at Kilauea originate primarily from the summit caldera or along one of the lengthy E and SW rift zones that extend from the caldera to the sea. About 90% of the surface of Kilauea is formed of lava flows less than about 1,100 years old; 70% of the volcano's surface is younger than 600 years. A long-term eruption from the East rift zone that began in 1983 has produced lava flows covering more than 100 sq km, destroying nearly 200 houses and adding new coastline to the island.
Map
Source: US Geological Survey Hawaiian Volcano Observatory (HVO)
Kilauea Information from the Global Volcanism Program
KIRISHIMA Kyushu 31.931°N, 130.864°E; summit elev. 1700 m
Based on notifications from JMA and pilot observations, the Tokyo VAAC reported that an eruption from Kirishima's Shinmoe-dake (Shinmoe peak) on 13 March produced ash plumes that rose to altitudes of 5.5-6.1 km (18,000-20,000 ft) a.s.l. Some plumes drifted E. According to news sources, people within 1.6 km evacuated and windows more than 6 km away shattered.
Geologic Summary. Kirishima is a large group of more than 20 Quaternary volcanoes located north of Kagoshima Bay. The late-Pleistocene to Holocene volcano group consists of stratovolcanoes, pyroclastic cones, maars, and underlying shield volcanoes located over an area of 20 x 30 km. The larger stratovolcanoes are scattered throughout the field, with the centrally located, 1,700-m-high Karakuni-dake being the highest. Onami-ike and Mi-ike, the two largest maars, are located SW of Karakuni-dake and at its far eastern end, respectively. Holocene eruptions have been concentrated along an E-W line of vents from Mi-ike to Ohachi, and at Shinmoe-dake to the NE. Frequent small-to-moderate explosive eruptions have been recorded since the 8th century.
Map
Sources: Tokyo Volcanic Ash Advisory Center (VAAC), Daily Mail
Kirishima Information from the Global Volcanism Program
SANTA MARIA Guatemala 14.756°N, 91.552°W; summit elev. 3772 m
INSIVUMEH reported that during 8-9 March a pyroclastic flow from Santa María's Santiaguito lava dome complex traveled down the E flank, depositing material in Rio Nima I. An ash plume rose 1 km and drifted E. Ashfall was reported in Quetzaltenango (10 km NNE) and Retalhuleu (27 km SW) from plumes produced during the previous few days. Based on analyses of satellite imagery, the Washington VAAC reported that ash-and-gas plumes drifted 22 km SW and 19 km W on 10 March.
Geologic Summary. Symmetrical, forest-covered Santa María volcano is one of a chain of large stratovolcanoes that rises dramatically above the Pacific coastal plain of Guatemala. The stratovolcano has a sharp-topped, conical profile that is cut on the SW flank by a large, 1-km-wide crater, which formed during a catastrophic eruption in 1902 and extends from just below the summit to the lower flank. The renowned Plinian eruption of 1902 followed a long repose period and devastated much of SW Guatemala. The large dacitic Santiaguito lava-dome complex has been growing at the base of the 1902 crater since 1922. Compound dome growth at Santiaguito has occurred episodically from four westward-younging vents, accompanied by almost continuous minor explosions and periodic lava extrusion, larger explosions, pyroclastic flows, and lahars.
Map
Sources: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hid..., Washington Volcanic Ash Advisory Center (VAAC)
Santa María Information from the Global Volcanism Program
http://www.volcano.si.edu/reports/usgs/
