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Smithsonian/USGS Weekly Volcanic Activity Report 2-8 February 2011
From: "Kuhn, Sally" <KUHNS@si.edu>
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Smithsonian/USGS Weekly Volcanic Activity Report
2-8 February 2011
Sally Kuhn Sennert - Weekly Report Editor
kuhns@si.edu
URL: http://www.volcano.si.edu/reports/usgs/
New Activity/Unrest: | Fuego, Guatemala | Galeras, Colombia | Kirishima, Kyushu | Nyiragongo, Democratic Republic of Congo
Ongoing Activity: | Bezymianny, Central Kamchatka (Russia) | Karymsky, Eastern Kamchatka (Russia) | Kilauea, Hawaii (USA) | Kizimen, Eastern Kamchatka (Russia) | Popocatépetl, México | Sakura-jima, Kyushu | Santa María, Guatemala | Shiveluch, Central Kamchatka (Russia) | Suwanose-jima, Ryukyu Islands (Japan) | Tengger Caldera, Eastern Java (Indonesia) | Villarrica, Central Chile
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
FUEGO Guatemala 14.473°N, 90.880°W; summit elev. 3763 m
INSIVUMEH reported that during 2-3 February Fuego produced 27 explosions with ash plumes that rose 300-500 m above the crater and drifted 7 km W and SW. The explosions generated shock waves detected as far away as 5 km W and SW, in Sangre de Cristo, Panimache I and II, and Morelia. Block avalanches descended the Santa Teresa, Taniluyá, Cenizas, and Trinidad drainages to the SW. During 6-8 February explosions produced ash plumes that rose 500 m above the crater and drifted W and SW. At night incandescence was observed emanating from the crater and explosions sometimes ejected incandescent material 100 m above the crater rim.
Geologic Summary. Volcán Fuego, one of Central America's most active volcanoes, is one of three large stratovolcanoes overlooking Guatemala's former capital, Antigua. The scarp of an older edifice, Meseta, lies between 3,763-m-high Fuego and its twin volcano to the N, Acatenango. Construction of Meseta volcano continued until the late Pleistocene or early Holocene, after which growth of the modern Fuego volcano continued the southward migration of volcanism that began at Acatenango. Frequent vigorous historical eruptions have been recorded at Fuego since the onset of the Spanish era in 1524, and have produced major ashfalls, along with occasional pyroclastic flows and lava flows. The last major explosive eruption from Fuego took place in 1974, producing spectacular pyroclastic flows visible from Antigua.
Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH) http://www.insivumeh.gob.gt/geofisica/boletin%20formato.htm
GALERAS Colombia 1.22°N, 77.37°W; summit elev. 4276 m
On 8 February, INGEOMINAS reported that "tornillo-type" earthquakes from Galeras had not been detected since 5 February. Seismic levels continued to fluctuate. On 6 February an overflight revealed that gas emissions had increased in comparison to the previous week, forming plumes that drifted NW. The Alert Level was lowered to III (Yellow; "changes in the behavior of volcanic activity").
Geologic Summary. Galeras, a stratovolcano with a large breached caldera located immediately W of the city of Pasto, is one of Colombia's most frequently active volcanoes. The dominantly andesitic Galeras volcanic complex has been active for more than 1 million years, and two major caldera collapse eruptions took place during the late Pleistocene. Longterm extensive hydrothermal alteration has affected the volcano. This has contributed to large-scale edifice collapse that has occurred on at least three occasions, producing debris avalanches that swept to the W and left a large horseshoe-shaped caldera inside which the modern cone has been constructed. Major explosive eruptions since the mid Holocene have produced widespread tephra deposits and pyroclastic flows that swept all but the southern flanks. A central cone slightly lower than the caldera rim has been the site of numerous small-to-moderate historical eruptions since the time of the Spanish conquistadors.
Source: Instituto Colombiano de Geología y Minería (INGEOMINAS) http://www.ingeominas.gov.co//
KIRISHIMA Kyushu 31.931°N, 130.864°E; summit elev. 1700 m
According to a news article, explosions on 2 February from Shinmoe-dake (Shinmoe peak), a stratovolcano of the Kirishima volcano group, disrupted flights to Tokyo. The article also noted that JMA widened the restricted zone to a 4-km-radius around the crater. About 600 people from Miyazaki (55 km E) had evacuated.
Based on reports from JMA, analyses of satellite imagery, and pilot observations, the Tokyo VAAC reported that during 2-8 February ash plumes rose to altitudes of 1.5-4.6 km (5,000-15,000 ft) a.s.l. and drifted SE. On 3 February, a pilot noted that an ash plume rose to an altitude of 9.1 km (30,000 ft) a.s.l. and drifted NE.
According to JMA, scientists observed Shinmoe-dake during an overflight on 6 February and noted that the lava dome was about 600 m in diameter, similar to observations from four days prior. Gas plumes rose from the edges of the lava dome, from multiple areas on the E side of the dome, and from a central vent. Ash plumes rose 1.5 km above the crater rim and drifted SE.
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.
Sources: Earthquake Research Institute http://www.eri.u-tokyo.ac.jp/,
Japan Meteorological Agency http://www.jma.go.jp/jma/indexe.html,
Tokyo Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/OTH/JP/messages.html,
Asia One http://www.asiaone.com/News/Latest+News/Asia/Story/A1Story20110202-261714.html
NYIRAGONGO Democratic Republic of Congo 1.52°S, 29.25°E; summit elev. 3470 m
The Toulouse VAAC reported that during 4-5 February diffuse plumes, likely composed primarily of sulfur dioxide gas, were observed in satellite imagery.
Geologic Summary. One of Africa's most notable volcanoes, Nyiragongo contained an active lava lake in its deep summit crater that drained catastrophically through its outer flanks in 1977. In contrast to the low profile of its neighboring shield volcano, Nyamuragira, Nyiragongo displays the steep slopes of a stratovolcano. Benches in the steep-walled, 1.2-km-wide summit crater mark the levels of former lava lakes, which have been observed since the late 19th century. About 100 parasitic cones are located on the volcano's flanks and along a NE-SW zone extending as far as Lake Kivu. Monitoring is done from a small observatory building located in Goma, ~18 km S of the Nyiragongo crater.
Source: Toulouse Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/OTH/FR/messages.html
Ongoing Activity
BEZYMIANNY Central Kamchatka (Russia) 55.978°N, 160.587°E; summit elev. 2882 m
KVERT reported that during 28 January-4 February seismicity from Bezymianny did not exceed background levels, however weak volcanic earthquakes were detected. A thermal anomaly over the volcano was observed daily in satellite imagery. Gas and steam activity was observed during 30-31 January and 1-3 February; cloud cover prevented observations on the other days. The Aviation Color Code level remained at Yellow.
Based on information from the Yelizovo Airport (UHPP), the Tokyo VAAC reported that on 4 February an ash plume rose to an altitude of 4.6 km (15,000 ft) a.s.l. drifted NE.
Geologic Summary. Prior to its noted 1955-56 eruption, Bezymianny volcano had been considered extinct. Three periods of intensified activity have occurred during the past 3,000 years. The latest period, which was preceded by a 1,000-year quiescence, began with the dramatic 1955-56 eruption. That eruption, similar to the 1980 event at Mount St. Helens, produced a large horseshoe-shaped crater that was formed by collapse of the summit and an associated lateral blast. Subsequent episodic but ongoing lava-dome growth, accompanied by intermittent explosive activity and pyroclastic flows, has largely filled the 1956 crater.
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php,
Tokyo Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/OTH/JP/messages.html
KARYMSKY Eastern Kamchatka (Russia) 54.05°N, 159.45°E; summit elev. 1536 m
KVERT reported that moderate seismic activity was detected at Karymsky during 28 January-4 February. Seismic data showed that possible ash plumes rose to an altitude of 4.7 km (15,400 ft) a.s.l. Satellite imagery showed a daily thermal anomaly, and ash plumes were observed drifting 120 km E during 30-31 January and 1-2 February. The Aviation Color Code remained at Orange.
Geologic Summary. Karymsky, the most active volcano of Kamchatka's eastern volcanic zone, is a symmetrical stratovolcano constructed within a 5-km-wide caldera that formed about 7,600-7,700 radiocarbon years ago. Construction of the Karymsky stratovolcano began about 2,000 years later. The latest eruptive period began about 500 years ago, following a 2,300-year quiescence. Much of the cone is mantled by lava flows less than 200 years old. Historical eruptions have been Vulcanian or Vulcanian-Strombolian with moderate explosive activity and occasional lava flows from the summit crater. Most seismicity preceding Karymsky eruptions has originated beneath Akademia Nauk caldera, which is located immediately S of Karymsky volcano and erupted simultaneously with Karymsky in 1996.
Source: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php
KILAUEA Hawaii (USA) 19.421°N, 155.287°W; summit elev. 1222 m
During 2-8 February, activity continued from the summit caldera and east rift zone. At the summit caldera, the level of the lava-pool surface in the deep pit within Halema'uma'u crater circulated and remained mostly stable at approximately 100 m below the crater floor, periodically rising or falling. Nighttime incandescence was visible from the Jaggar Museum on the NW caldera rim. A plume from the vent that drifted mostly SW, W, and N deposited ash and fresh spatter nearby.
At the east rift zone, lava that broke out of the Quarry tube in a saddle between two rootless shields around 610 m elevation continued to advance both E and W, producing scattered surface flows. At the lowest elevation of the E branch, lava advanced along Highway 130 near Kalapana, periodically burning vegetation, and to the S towards the coast. On 4 February incandescence from the TEB vent and upper rootless shields visible on the web camera was later confirmed to be from spatter and lava flows. Lava continued to issue from each location during 5-8 February. Multiple small ocean entries were active on the W part of the Puhi-o-Kalaikini lava delta until 7 or 8 February.
In Pu'u 'O'o crater, incandescence emanated from the fuming vent in the E wall of the crater, and spatter and lava flows were produced from a cone on the N portion of the crater floor. On 7 February activity significantly increased; lava flowed from several vents including the vent on the E wall and multiple spatter cones on the N and NW areas of the floor.
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.
Source: US Geological Survey Hawaiian Volcano Observatory (HVO) http://hvo.wr.usgs.gov/
KIZIMEN Eastern Kamchatka (Russia) 55.130°N, 160.32°E; summit elev. 2376 m
KVERT reported that during 28 January-4 February seismicity from Kizimen was high but variable, and many shallow volcanic earthquakes as well as volcanic tremor continued to be detected. Satellite images showed a bright thermal anomaly over the volcano daily. During 27-31 January and 1-3 February ash plumes rose to an altitude of 6.1 km (16,400 ft) a.s.l. and drifted more than 430 km E. The Aviation Color Code remained at Orange.
Based on information from KEMSD, the Tokyo VAAC reported that on 8 February an eruption produced a plume that rose to an altitude of 4 km (13,000 ft) a.s.l.
Geologic Summary. Kizimen is an isolated, conical stratovolcano that is morphologically similar to Mount St. Helens prior to its 1980 eruption. The summit of Kizimen consists of overlapping lava domes, and blocky lava flows descend the flanks of the volcano, which is the westernmost of a volcanic chain north of Kronotsky volcano. The 2,376-m-high Kizimen was formed during four eruptive cycles beginning about 12,000 years ago and lasting 2,000-3,500 years. The largest eruptions took place about 10,000 and 8300-8400 years ago, and three periods of longterm lava-dome growth have occurred. The latest eruptive cycle began about 3,000 years ago with a large explosion and was followed by lava-dome growth lasting intermittently about 1,000 years. An explosive eruption about 1,100 years ago produced a lateral blast and created a 1.0 x 0.7 km wide crater breached to the NE, inside which a small lava dome (the fourth at Kizimen) has grown. A single explosive eruption, during 1927-28, has been recorded in historical time.
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php,
Tokyo Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/OTH/JP/messages.html
POPOCATEPETL México 19.023°N, 98.622°W; summit elev. 5426 m
CENAPRED noted that steam-and-gas emissions rose from Popocatépetl during 2-8 February.
Geologic Summary. Popocatépetl, whose name is the Aztec word for smoking mountain, towers to 5,426 m 70 km SE of Mexico City and is North America's second-highest volcano. Frequent historical eruptions have been recorded since the beginning of the Spanish colonial era. A small eruption on 21 December 1994 ended five decades of quiescence. Since 1996 small lava domes have incrementally been constructed within the summit crater and destroyed by explosive eruptions. Intermittent small-to-moderate gas-and-ash eruptions have continued, occasionally producing ashfall in neighboring towns and villages.
Source: Centro Nacional de Prevencion de Desastres (CENAPRED) http://www.cenapred.unam.mx/es/
SAKURA-JIMA Kyushu 31.585°N, 130.657°E; summit elev. 1117 m
Based on information from JMA, the Tokyo VAAC reported that during 1-8 February explosions from Sakura-jima produced plumes that rose to altitudes of 1.2-3.4 km (4,000-11,000 ft) a.s.l. and drifted SE, E, and NE. During 3-4 and 7 February, pilots reported that ash plumes rose to altitudes of 2.4-3 km (8,000-10,000 ft) a.s.l. According to a news article, an eruption on 8 February produced a gas-and-ash plume that rose 2 km. A large amount of ashfall prompted local authorities to temporarily ban residents from driving near the area.
Geologic Summary. Sakura-jima, one of Japan's most active volcanoes, is a post-caldera cone of the Aira caldera at the northern half of Kagoshima Bay. Eruption of the voluminous Ito pyroclastic flow was associated with the formation of the 17 x 23-km-wide Aira caldera about 22,000 years ago. The construction of Sakura-jima began about 13,000 years ago and built an island that was finally joined to the Osumi Peninsula during the major explosive and effusive eruption of 1914. Activity at the Kita-dake summit cone ended about 4,850 years ago, after which eruptions took place at Minami-dake. Frequent historical eruptions, recorded since the 8th century, have deposited ash on Kagoshima, one of Kyushu's largest cities, located across Kagoshima Bay only 8 km from the summit. The largest historical eruption took place during 1471-76.
Sources: Tokyo Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/OTH/JP/messages.html,
Arirang http://www.arirang.co.kr/News/News_View.asp?nseq=112364&code=Ne2&category=2
SANTA MARIA Guatemala 14.756°N, 91.552°W; summit elev. 3772 m
Based on analyses of satellite imagery, the Washington VAAC reported that on 2 February an ash plume from Santa María's Santiaguito lava dome complex drifted less than 30 km SW and quickly dissipated. INSIVUMEH reported that during 2-3 February explosions produced ash plumes that rose 300 m above Caliente dome and drifted S and SW. On 4 February the VAAC noted that an ash plume was detected in satellite imagery. INSIVUMEH notices also stated that fumarolic plumes rose as high as 150 m above the dome during 2-3 and 6-7 February and drifted SE and W. Several landslides on the flanks occurred during 6-7 February. Explosions during 7-8 February produced ash plumes that rose 400 m above the dome and drifted SE.
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.
Sources: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH) http://www.ssd.noaa.gov/VAAC/messages.html,
Washington Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/messages.html
SHIVELUCH Central Kamchatka (Russia) 56.653°N, 161.360°E; summit elev. 3283 m
KVERT reported that moderate seismic activity was detected at Shiveluch during 28 January-4 February and many volcanic earthquakes were detected. A thermal anomaly over the lava dome was observed in satellite imagery. Gas and steam activity was occasionally observed. Ash plumes were seen rising to an altitude of 6 km (19,700 ft) a.s.l. on 30 January and 3 February. Ash plumes observed in satellite imagery drifted 120 km NE during 31 Janaury-1 February, and rose to altitudes of 6-8 km (19,700-26,200 ft) a.s.l. on 1 February. The Aviation Color Code remained at Orange.
The Tokyo VAAC reported that on 8 February a possible eruption detected in satellite imagery produced a plume that rose to an altitude of 4 km (13,000 ft) a.s.l. and drifted E. Subsequent notices that day stated that ash had dissipated.
Geologic Summary. The high, isolated massif of Shiveluch volcano (also spelled Sheveluch) rises above the lowlands NNE of the Kliuchevskaya volcano group and forms one of Kamchatka's largest and most active volcanoes. The currently active Molodoy Shiveluch lava-dome complex was constructed during the Holocene within a large breached caldera formed by collapse of the massive late-Pleistocene Strary Shiveluch volcano. At least 60 large eruptions of Shiveluch have occurred during the Holocene, making it the most vigorous andesitic volcano of the Kuril-Kamchatka arc. Frequent collapses of lava-dome complexes, most recently in 1964, have produced large debris avalanches whose deposits cover much of the floor of the breached caldera. Intermittent explosive eruptions began in the 1990s from a new lava dome that began growing in 1980. The largest historical eruptions from Shiveluch occurred in 1854 and 1964.
Sources: Kamchatkan Volcanic Eruption Response Team (KVERT) http://www.kscnet.ru/ivs/kvert/index_eng.php,
Tokyo Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/OTH/JP/messages.html
SUWANOSE-JIMA Ryukyu Islands (Japan) 29.635°N, 129.716°E; summit elev. 799 m
Based on a pilot observation, the Tokyo VAAC reported that on 5 February an ash plume from Suwanose-jima rose to an altitude of 0.7 km (2,000 ft) a.s.l. and drifted S. Explosions during 5-7 February were noted by JMA.
Geologic Summary. The 8-km-long, spindle-shaped island of Suwanose-jima in the northern Ryukyu Islands consists of an andesitic stratovolcano with two historically active summit craters. Only about 50 persons live on the sparsely populated island. The summit of the volcano is truncated by a large breached crater extending to the sea on the east flank that was formed by edifice collapse. Suwanose-jima, one of Japan's most frequently active volcanoes, was in a state of intermittent Strombolian activity from On-take, the NE summit crater, that began in 1949 and lasted nearly a half century. The largest historical eruption took place in 1813-14, when thick scoria deposits blanketed residential areas, after which the island was uninhabited for about 70 years. The SW crater produced lava flows that reached the western coast in 1813, and lava flows reached the eastern coast of the island in 1884.
Source: Tokyo Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/OTH/JP/messages.html
TENGGER CALDERA Eastern Java (Indonesia) 7.942°S, 112.95°E; summit elev. 2329 m
CVGHM reported that on 5 February volcanic bombs ejected from Tengger Caldera's Bromo cone were found 1.2-1.4 km from the crater rim. During 5-8 February gray-to-brown ash plumes rose 400-800 m above the crater and drifted ENE. Incandescent material was ejected 200-300 m above the crater and landed as far as 500 m away. Roaring and booming noises were noted. Ash fell at the Bromo observation post, and in nearby villages including Ngadirejo (10 km WNW), Sukapura (14 km NE), and Sumber (18 km E). High-amplitude seismicity and volcanic tremor were detected. Deformation measurements had remained stable since 31 December 2010. The Alert Level remained at 3 (on a scale of 1-4). Residents and tourists were not permitted within a 2-km-radius of the active crater.
Geologic Summary. The 16-km-wide Tengger caldera in eastern Java is located at the northern end of a volcanic massif extending from Semeru volcano. The massive Tengger volcanic complex consists of five overlapping stratovolcanoes, each truncated by a caldera. The most recent is the 9 x 10 km wide Sandsea caldera, which formed incrementally during the late Pleistocene and early Holocene. An overlapping cluster of post-caldera cones was constructed on the floor of the Sandsea caldera within the past several thousand years. The youngest of these is Bromo, one of Java's most frequently visited and most active volcanoes. More than 50 mild-to-moderate explosive eruptions have occurred since 1804.
Source: Center of Volcanology and Geological Hazard Mitigation (CVGHM) http://www.vsi.esdm.go.id/
VILLARRICA Central Chile 39.42°S, 71.93°W; summit elev. 2847 m
Based on web camera views, the Buenos Aires VAAC reported that on 7 February diffuse gas-and-steam plumes rose from Villarrica and quickly dissipated.
Geologic Summary. Villarrica, one of Chile's most active volcanoes, rises above the lake and town of the same name. It is the westernmost of three large stratovolcanoes that trend perpendicular to the Andean chain. A 6-km wide caldera formed during the late Pleistocene, more than 0.9 million years ago. A 2-km-wide postglacial caldera is located at the base of the presently active, dominantly basaltic-to-andesitic cone at the NW margin of the Pleistocene caldera. About 25 scoria cones dot Villarrica's flanks. Plinian eruptions and pyroclastic flows have been produced during the Holocene from this dominantly basaltic volcano, but historical eruptions have consisted largely of mild-to-moderate explosive activity with occasional lava effusion. Lahars from the glacier-covered volcano have damaged towns on its flanks.
Source: Buenos Aires Volcanic Ash Advisory Center (VAAC) http://www.ssd.noaa.gov/VAAC/OTH/AG/messages.html
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