Volcanoes

[Shammu]

CHAITEN

As of the 4th of December, the Global Volcanism Network (GVN) reported that based on observations of satellite imagery, pilot reports, SIGMET notices, and web camera views, the Buenos Aires VAAC reported that on 23, 25, 27, and 29th of November, and the 2nd of December, ash plumes from Chaitén rose to altitudes 1.8-3 km (6,000-10,000 ft) a.s.l. and drifted SE and NNW. A thermal anomaly was detected on satellite imagery on the 25th and 29th of November.

The Current Colour Code for Chaiten is currently at the RED
~~~~~~~~~

SUWANOSE-JIMA

As of the 27th of November, the Japan Meteorlogical Agency (JMA) has reported that based on information from JMA, the Tokyo VAAC reported an eruption from Suwanose-jima on 21 November. A plume rose to an altitude of 1.5 km (5,000 ft) a.s.l. and drifted E. An explosion was reported on 25 November.

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 E 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 (also called Otake), 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.(JMA)

The Current Colour Code for Suwanose-Jima is currently at the YELLOW
~~~~~~~~~

DUKONO

As of the 27th of November, the Volcano Society of Indonesia (VSI) has reported to INTLVRC that based on analysis of satellite imagery, the Darwin VAAC reported that on the 20th of November an ash plume from Dukono rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted 110 km NW.

Reports from this remote volcano in northernmost Halmahera are rare, but Dukono has been one of Indonesia's most active volcanoes. More-or-less continuous explosive eruptions, sometimes accompanied by lava flows, occurred from 1933 until at least the mid-1990s, when routine observations were curtailed. During a major eruption in 1550, a lava flow filled in the strait between Halmahera and the north-flank cone of Gunung Mamuya. Dukono is a complex volcano presenting a broad, low profile with multiple summit peaks and overlapping craters. Malupang Wariang, 1 km SW of Dukono's summit crater complex, contains a 700 x 570 m crater that has also been active during historical time.

The Current Colour Code for Dukono is currently at the ALERT LEVEL 1

[Shammu]

GALERAS

As of the 4th of December, the Observatory Vulcanológico and Sismológico de Pasto - INGEOMINAS, informs that the seismic activity that predominates continues associate with processes related to flowed sources of movement of inside the volcanic system, that in surface is reflected with the fluctuating degassing of the system. Generally, the seismicity registered diminution with respect to the levels of the last month. Also lapses of several hours are appearing in which the seismicity is reduced well-known. Concerning manifestations of the activity in surface, the noticeable fact registered the 30th of November related to a process of ash emission that was associated with an episode of spasmodic tremor that began towards 0218 hrs with a duration near 30 minutes. The emission was characterised by the fine ash presence that basically dispersed towards the south and the south-southwest with respect to the volcano in sites like High Gualmatán, High Cubiján, Marqueza Alto and Cobanegra to distances with respect to the main crater of 7, 12,5, 7,5 and 6 km respectively. Thicknesses of ash were observed smaller 1 mm East event appeared as much after a remarkable diminution in number as in energy of the seismic events of transitory character. During the last week the maximum daily value of Dioxide emission of Azufre (SO2) to the atmosphere, registered the 29th of November, with a value near the 700 tonnes. The general evaluation of the phenomenon stays under which the existence of a magmatic body in surfaces is demonstrated, that a degassing process maintains fluctuating, and that is showing cooling evidences, solidification and possible obstruction of conduits which can favor the occurrence of episodes at least similar to registered the 30th of November. The presence of that magmatic material in surface, in the form of dome, deserves special attention to the evolution of the process, without so far it implies a change in the activity level.

Galeras, a stratovolcano with a large breached caldera located immediately west 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. Long-term 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 west 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.

The Current Colour Code for Galeras is currently at LEVEL III
~~~~~~~~

NEVADO del HUILA

As of the 27th of November, the National Institute Of Sismología, Volcanology, Meteorology And Hidrologia, INGEOMINAS reported that an eruption of Nevado del Huila at 2145 hrs on 20 November that destroyed part of a new lava dome that had formed during the previous months. The Alert Level was raised to Red (on a 4-color scale where Red is the highest level). According to the Washington VAAC, two gas-and-ash plumes rose to altitudes of 12.4-15.4 km (40,700-50,500 ft) a.s.l. and drifted W and SE. Hot material erupted at the summit melted areas of the surrounding glacier and caused lahars in the Bellavista and Páez rivers. Lahars in the Páez River damaged infrastructure and destroyed homes, and residents of Taravira, Tóez, and La Estrella reported abundant ashfall and noises associated with both the eruption and the lahar. There may have been as many as 10 fatalities and 10 others were missing, and several populations were left without means of communication. By the time of a report at 0230 on 21 November, the seismicity had decreased. During an overflight, scientists observed a 400-m-dimater crater in the SW area of Pico Central. A lava dome inside the crater was degassing. Intense fumarolic activity was noted from the W end of a crack generated in April 2007. The next day, the Alert Level was lowered back to Orange because seismicity had returned to background levels. INGEOMINAS continued to receive reports of sulfur odors and continuous gas emissions from the summit. According to news reports, the lahars damaged or destroyed about 70 homes and several bridges, and displaced many families. Hundreds of people were evacuated.

The Current Colour Code for Nevado del Huila is currently at ORANGE
~~~~~~~~~

PACAYA

As of the 4th of December, the National Institute Of Sismología, Volcanology, Meteorology And Hidrologia, (INSIVUMEH) has reported that for Atmospheric Conditions: Partially Dimmed. Pluvial Precipitation: 0.0 mm. Wind speed: 32.0 km/hr. Direction: Southwest. Activity: Moderate fumaroles in a southwestern direction. Continuous the effusive activity with 3 lava flows, one to the west with 100 metres in length and other two to the southwest, with 100 and 150 metres in length. The seismic activity registers events associated superficial type “B” or to activity of small explosions on the crater.

The eruptions from Pacaya, one of Guatemala's most active volcanoes, are frequently visible from Guatemala City, the nation's capital. Pacaya is a complex basaltic volcano constructed just outside the southern topographic rim of the 14 x 16 km Pleistocene Amatitlán caldera. A cluster of dacitic lava domes occupies the southern caldera floor. The post-caldera Pacaya massif includes the Cerro Grande lava dome and a younger volcano to the SW. Collapse of Pacaya volcano about 1100 years ago produced a debris-avalanche deposit that extends 25 km onto the Pacific coastal plain and left an arcuate somma rim inside which the modern Pacaya volcano (MacKenney cone) grew. A subsidiary crater, Cerro Chino, was constructed on the NW somma rim and was last active in the 19th century. During the past several decades, activity at Pacaya has consisted of frequent strombolian eruptions with intermittent lava flow extrusion that has partially filled in the caldera moat and armored the flanks of MacKenney cone, punctuated by occasional larger explosive eruptions that partially destroy the summit of the cone.

The Current Colour Code for Pacaya is currently at ORANGE

[Shammu]

FUEGO

As of the 4th of December, the National Institute Of Sismología, Volcanology, Meteorology And Hidrologia, (INSIVUMEH) has reported that for Atmospheric Conditions: Cleared. Pluvial Precipitation: 0.0 mm. Wind speed: 40.0 km/hr. Direction: Southwest. Activity: Constant avalanches of blocks in weak and moderate form on the southwestern flank. 10 explosions, 2 weak and 8 moderate ones have been observed, expelling gray ash to 300, 700 and 1000 metres moving to the south and southwest, by 10 kilometres. These explosions are being accompanied moderate rumblings and sensible shock waves to 7 km of the volcano. Also, degassing sounds similar to a train locomotive were generated, with lapses of 3 to 15 minutes. The lava flow stays in the Ash-gray ravine with approximated length of 150 metres.

The 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 3763-m-high Fuego and its twin volcano to the north, Acatenango. Construction of Meseta volcano dates back to about 230,000 years and continued until the late Pleistocene or early Holocene. Collapse of Meseta volcano may have produced the massive Escuintla debris-avalanche deposit, which extends about 50 km onto the Pacific coastal plain. Growth of the modern Fuego volcano followed, continuing the southward migration of volcanism that began at Acatenango. In contrast to the mostly andesitic Acatenango volcano, eruptions at Fuego have become more mafic with time, and most historical activity has produced basaltic rocks. 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 Current Colour Code for Fuego is currently at ORANGE
~~~~~~~~~

SANTA MARIA

As of the 4th of December, the National Institute Of Sismología, Volcanology, Meteorology And Hidrologia, (INSIVUMEH) has reported that for Atmospheric Conditions: Cleared. Pluvial Precipitation: 0.0 mm. Wind speed: 4.0 km/hr. Direction: South & Southeast. Activity: Dispersed ash curtains even exist in the volcanic area, this is caused by the removal of ash-gray release, which the dispersed strong wind in several directions and is dragged to several kilometres of the volcano even on Quetzaltenango and parts of the South coast. In the morning 2 explosions have been registered, a weak and a moderate one, expelling gray ash to 300 and 600 metres dispersing to the southeast, on the properties of this zone.

The symmetrical, forest-covered Santa María volcano is one of the most prominent of a chain of large stratovolcanoes that rises dramatically above the Pacific coastal plain of Guatemala. The 3772-m-high stratovolcano has a sharp-topped, conical profile that is cut on the SW flank by a large, 1.5-km-wide crater. The oval-shaped crater extends from just below the summit of Volcán Santa María to the lower flank and was formed during a catastrophic eruption in 1902. The renowned plinian eruption of 1902 that devastated much of SW Guatemala followed a long repose period after construction of the large basaltic-andesite stratovolcano. The massive 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, the most recent of which is Caliente. Dome growth has been accompanied by almost continuous minor explosions, with periodic lava extrusion, larger explosions, pyroclastic flows, and lahars.

The Current Colour Code for Santa Maria is currently at ORANGE
~~~~~~~~~~~

SOUFRIERE HILLS

As of the 4th of December, the Monstserrat Volcano Observatory (MVO) reported that they observed an ash emission around 0045Z and subsequent imagery to 0115X showed a puff extending 17.25 mi to the WSW. Based on observed speed and movement...estimated height is placed at 280,000 ft. Earlier emissions are not currently seen in satellite imagery.

There was an explosion and pyroclastic flow at the Soufriere Hills Volcano at approximately 2135 hrs local time on the 2nd of December 2008. The explosion happened without any warning. There was no precursory seismic activity. The explosion appears to have taken place on the western side of the lava dome. The explosion sent large blocks to distances up to a kilometre from the dome. Incandescent blocks were scattered over the north-westen side of Gages mountain which implies a vertical element to the explosion. There have been no reports of air-fall pumice or ballistics in inhabited areas. The pyroclastic flow was on the western flank of the volcano. It travelled down Gages Valley and into Plymouth and appears to have reached the sea. Buildings were set alight in Plymouth and could be seen burning from Salem for several hours afterwards. The explosion and pyroclastic flow both generated ash columns and these were accompanied by lightning strikes. It was not possible to estimate the height of the ash columns. The ash was blown to the west and there have been no reports of ash fall in inhabited areas. The Hazard Level is 3.

The complex, dominantly andesitic Soufrière Hills volcano occupies the southern half of the island of Montserrat. The summit area consists primarily of a series of lava domes emplaced along an ESE-trending zone. English's Crater, a 1-km-wide crater breached widely to the east, was formed during an eruption about 4000 years ago in which the summit collapsed, producing a large submarine debris avalanche. Block-and-ash flow and surge deposits associated with dome growth predominate in flank deposits at Soufrière Hills. Non-eruptive seismic swarms occurred at 30-year intervals in the 20th century, but with the exception of a 17th-century eruption that produced the Castle Peak lava dome, no historical eruptions were recorded on Montserrat until 1995. Long-term small-to-moderate ash eruptions beginning in that year were later accompanied by lava-dome growth and pyroclastic flows that forced evacuation of the southern half of the island and ultimately destroyed the capital city of Plymouth, causing major social and economic disruption.

The Current Colour Code for Soufriere Hills is currently at ALERT LEVEL 3

[Shammu]

UBINAS

As of the 4th December, the El Observatorio Volcanológico de los Andes del Sur (OVDAS-SERNAGEOMIN) reported that based on a SIGMET notice, the Buenos Aires VAAC reported that on 30 November an ash plume from Ubinas rose to altitudes of 5.5-6.1 km (18,000-20,000 ft) a.s.l. and drifted SW.

A small, 1.4-km-wide caldera cuts the top of Ubinas, Peru's most active volcano, giving it a truncated appearance. Ubinas is the northernmost of three young volcanoes located along a regional structural lineament about 50 km behind the main volcanic front of Perú. The growth and destruction of Ubinas I volcano was followed by construction of Ubinas II volcano beginning in the mid-Pleistocene. The upper slopes of the andesitic-to-rhyolitic Ubinas II stratovolcano are composed primarily of andesitic and trachyandesitic lava flows and steepen to nearly 45 degrees. The steep-walled, 150-m-deep summit caldera contains an ash cone with a 500-m-wide funnel-shaped vent that is 200 m deep. Debris-avalanche deposits from the collapse of the SE flank of Ubinas about 3700 years ago extend 10 km from the volcano. Widespread plinian pumice-fall deposits from Ubinas include one of Holocene age about 1000 years ago. Holocene lava flows are visible on the volcano's flanks, but historical activity, documented since the 16th century, has consisted of intermittent minor-to-moderate explosive eruptions.

The Current Colour Code for Ubinas is currently at ORANGE
~~~~~~~~~~~

KLIUCHEVSKOI

As of the 4th of December, the Kamchatkan Volcanic Eruption Response Team (KVERT) has reported that seismic activity at Kliuchevskoi was above background levels during 21-28 November; Strombolian activity and lava effusion continued. On 21 November, a lava flow traveled 1.5-1.8 km down the NW flank. Gas-and-steam plumes drifted 80 km NW on 24 November and 20-40 km SE during 25-26 November. Gas-and-steam plumes containing slight amounts of ash rose to altitudes of 5.3-5.5 km (17,400-18,000 ft) a.s.l. during 26-27 November. Analysis of satellite imagery revealed a large daily thermal anomaly in the crater during 21-28 November. The Level of Concern Colour Code remained Orange.

Kliuchevskoi is Kamchatka's highest and most active volcano. Since its origin about 6000 years ago, the beautifully symmetrical, 4835-m-high basaltic stratovolcano has produced frequent moderate-volume explosive and effusive eruptions without major periods of inactivity. Kliuchevskoi rises above a saddle NE of sharp-peaked Kamen volcano and lies SE of the broad Ushkovsky massif. More than 100 flank eruptions have occurred at Kliuchevskoi during the past roughly 3000 years, with most lateral craters and cones occurring along radial fissures between the unconfined NE-to-SE flanks of the conical volcano between 500 m and 3600 m elevation. The morphology of its 700-m-wide summit crater has been frequently modified by historical eruptions, which have been recorded since the late-17th century. Historical eruptions have originated primarily from the summit crater, but have also included numerous major explosive and effusive eruptions from flank craters.

The Current Colour Code for Kliuchevskoi is currently at ORANGE
~~~~~~~~~~~~

KARYMSKY

As of the 28th of November, the Kamchatkan Volcanic Eruption Response Team (KVERT) has reported that activity of the volcano continues and ash explosions up to 6 km (or 19,700 ft.) ASL are possible. The explosive activity of the volcano could affect low-flying aircraft. Seismic activity of the volcano was above background levels on November 24-25, and at background levels in the other days of the week. According to seismic data, possibly ash-gas explosions up to 3.0 km (9,800 ft) ASL occurred at the volcano on November 23-25. According to visual data by volcanologists from a helicopter in the area of the volcano, gas-steam rose up to 2.0-2.4 km (6,600-7,900 ft) ASL. According to satellite data, a thermal anomaly was registered over the volcano on November 20th, 22nd and 24-26. Clouds obscured the volcano on the other days of the week.

Karymsky, the most active volcano of Kamchatka's eastern volcanic zone, is a symmetrical stratovolcano constructed within a 5-km-wide caldera that formed during the early Holocene. The caldera cuts the south side of the Pleistocene Dvor volcano and is located outside the north margin of the large mid-Pleistocene Polovinka caldera, which contains the smaller Akademia Nauk and Odnoboky calderas. Most seismicity preceding Karymsky eruptions originated beneath Akademia Nauk caldera, which is located immediately south of Karymsky volcano. The caldera enclosing Karymsky volcano formed about 7600-7700 radiocarbon years ago; construction of the Karymsky stratovolcano began about 2000 years later. The latest eruptive period began about 500 years ago, following a 2300-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.

The Current Colour Code for Karymsky is currently at ORANGE

[Shammu]

BEZYMIANNY

As of the 28th of November, the Kamchatkan Volcanic Eruption Response Team (KVERT) has reported that growth of the lava dome continues - possibly a viscous lava flow continues to effusing to the south-southeast flank of the dome. Sudden ash emission related to this activity could affect low-flying aircraft in the vicinity of the volcano. Strong seismicity of Klyuchevskoy volcano does not allow to detach a seismicity of Bezymianny volcano. A moderate fumarolic activity of the volcano was observed on web-camera on November 27-28. Clouds obscured the volcano in the other days of the week. According to satellite data, a weak thermal anomaly was registered over the lava dome on November 25th and 26th.

Prior to its noted 1955-56 eruption, Bezymianny volcano had been considered extinct. The modern Bezymianny volcano, much smaller in size than its massive neighbours Kamen and Kliuchevskoi, was formed about 4700 years ago over a late-Pleistocene lava-dome complex and an ancestral volcano that was built between about 11,000-7000 years ago. Three periods of intensified activity have occurred during the past 3000 years. The latest period, which was preceded by a 1000-year quiescence, began with the dramatic 1955-56 eruption. This eruption, similar to that of Mt. St. Helens in 1980, 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.

The Current Colour Code for Bezymianny is currently at YELLOW
~~~~~~~~~~~

SHEVELUCH

As of the 4th of December, the Kamchatkan Volcanic Eruption Response Team (KVERT) has reported to INTLVRC that seismic activity at Sheveluch was above background levels during 21-28 November. Based on interpretations of seismic data, ash plumes rose to an altitude of 5.6 km (18,400 ft) a.s.l. Ashfall was reported in the town of Klyuchi, about 30 km SW, on 22 November. Visual observations confirmed that ash plumes rose to an altitude of 5.5 km (18,000 ft) a.s.l. on 25 November. Fumarolic activity was visible on the web camera during 26-28 November. Analysis of satellite imagery revealed a daily thermal anomaly on the lava dome and a gas-and-steam plume that drifted about 30 km SE on 26 November. The Level of Concern Colour Code remained at Orange. Based on information from KEMSD and analysis of satellite imagery, the Tokyo VAAC reported that on 1 December eruptions produced plumes to an altitude of 4.9 km (16,000 ft) a.s.l.

The high, isolated massif of Sheveluch volcano (also spelled Shiveluch) rises above the lowlands NNE of the Kliuchevskoi volcano group. The 1300 cu km Shiveluch is one of Kamchatka's largest and most active volcanic structures. The summit of roughly 65,000-year-old Stary Shiveluch is truncated by a broad 9-km-wide late-Pleistocene caldera breached to the south. Many lava domes dot its outer flanks. The Molodoy Shiveluch lava dome complex was constructed during the Holocene within the large horseshoe-shaped caldera; Holocene lava dome extrusion also took place on the flanks of Stary Shiveluch. At least 60 large eruptions of Shiveluch have occurred during the Holocene, making it the most vigorous andesitic volcano of the Kuril-Kamchatka arc. Widespread tephra layers from these eruptions have provided valuable time markers for dating volcanic events in Kamchatka. Frequent collapses of dome complexes, most recently in 1964, have produced debris avalanches whose deposits cover much of the floor of the breached caldera.

The Current Colour Code for Sheveluch is currently at ORANGE
~~~~~~~~~~~

COLIMA

As of the 4th of December, the Government of the State, through the State Unit of Civil Defence-Colima reports that detected two exhalations during last the twenty-four hours, which has not caused reports on damages or affectation in the adjacent populations, according to information the Government into the State, through the State Unit of Civil Defense Colima. The zone where is the volcano finds cleared most of the time, but it continues the possibility of storm clouds, water precipitations and electrical activity; for that reason one reminds the population to avoid the permanence in bordering ravines, before the possibility of lahars (mud flows). Also, it follows the restriction effective for the overflights that do not have scientific aims or of civil defence, and is prohibited the permanence of people other people's to these activities in ravines of the volcano. According to the monitoring, this past Tuesday registered one more exhalation at 1614 hours; it was of white colour and, concerning the volcanic dome, went towards the West. This past Wednesday, however, detected an exhalation of gray colour at 1147 hours, that lifted to 380 metres on the level of the dome, in a vertical direction.

The Colima volcanic complex is the most prominent volcanic centre of the western Mexican Volcanic Belt. It consists of two southward-younging volcanoes, Nevado de Colima (the 4320 m high point of the complex) on the north and the 3850-m-high historically active Volcán de Colima at the south. A group of cinder cones of late-Pleistocene age is located on the floor of the Colima graben west and east of the Colima complex. Volcán de Colima (also known as Volcán Fuego) is a youthful stratovolcano constructed within a 5-km-wide caldera, breached to the south, that has been the source of large debris avalanches. Major slope failures have occurred repeatedly from both the Nevado and Colima cones, and have produced a thick apron of debris-avalanche deposits on three sides of the complex. Frequent historical eruptions date back to the 16th century. Occasional major explosive eruptions (most recently in 1913) have destroyed the summit and left a deep, steep-sided crater that was slowly refilled and then overtopped by lava dome growth.

The Current Colour Code for volcano Colima is YELLOW

[Shammu]

POPOCATEPETL

As of the 4th of December, the El Centro Nacional de Prevención de Desastres de la Secretaría de Gobernación (CENAPRED) has reported that in the last 24 hours the monitoring system again detected 23 low exhalations accompanied by steam and gas. The other monitored parameters remain without important changes. At the moment of this report CENAPRED can see the volcano with a steam and gas emissions with direction to the east. From high to low probability the expected activity scenarios in the next hours, days or weeks are: moderate exhalations, some with ash emissions; occasionally mild incandescence during nights and sporadic low level explosions with low probabilities of incandescent fragment at short distance to the crater. There is a permanent monitoring of the volcano to detect any change. The traffic light of volcanic alert remains in YELLOW Phase 2.

Volcano Popocatépetl, whose name is the Aztec word for smoking mountain, towers to 5426 m 70 km SE of Mexico City to form North America's 2nd-highest volcano. The glacier-clad stratovolcano contains a steep-walled, 250-450 m deep crater. The generally symmetrical volcano is modified by the sharp-peaked Ventorrillo on the NW, a remnant of an earlier volcano. At least three previous major cones were destroyed by gravitational failure during the Pleistocene, producing massive debris-avalanche deposits covering broad areas south of the volcano. The modern volcano was constructed to the south of the late-Pleistocene to Holocene El Fraile cone. Three major plinian eruptions, the most recent of which took place about 800 AD, have occurred from Popocatépetl since the mid Holocene, accompanied by pyroclastic flows and voluminous lahars that swept basins below the volcano. Frequent historical eruptions, first recorded in Aztec codices, have occurred since pre-columbian time.

The Current Colour Code for volcano Popocatepetl is YELLOW
~~~~~~~~~~

TUNGURAHUA

As of the 4th of December, the Instituto Geofísico (IG) has reported that seismic conditions of the volcano continue presenting/displaying low levels. Rains by the sector of the volcano have not appeared.

The IG reports that seismicity: In the last 24 hours, a total of 9 events of long period (LP) has been entered (LP). Observations, Emissions and Ash: In the morning the high part of the volcano was sprightly and fumarolic activity was not observed in the interior of the crater. Rains and Lahars: In the afternoon of yesterday and today, rains by the sector of the volcano have not been registered.

Tungurahua, a steep-sided andesitic-dacitic stratovolcano that towers more than 3 km above its northern base, is one of Ecuador's most active volcanoes. Three major volcanic edifices have been sequentially constructed since the mid-Pleistocene over a basement of metamorphic rocks. Tungurahua II was built within the past 14,000 years following the collapse of the initial edifice. Tungurahua II itself collapsed about 3000 years ago and produced a large debris-avalanche deposit and a horseshoe-shaped caldera open to the west, inside which the modern glacier-capped stratovolcano (Tungurahua III) was constructed. Historical eruptions have all originated from the summit crater. They have been accompanied by strong explosions and sometimes by pyroclastic flows and lava flows that reached populated areas at the volcano's base. Prior to a long-term eruption beginning in 1999 that caused the temporary evacuation of the city of Baños at the foot of the volcano, the last major eruption had occurred from 1916 to 1918, although minor activity continued until 1925.

The official colour of the volcanic alarm light remains on ORANGE
~~~~~~~~~~

REVENTADOR

As of the 27th of November, the Instituto Geofísico (IG) has reported that inclement weather prevented observations of Reventador during 19-23 November. A seismic station situated on the NE flank of the central cone recorded a high number of rockfall signals that presumably originated from the active lava-flow fronts.

In the last 24 hours a total of 8 volcano-tectonic events and 3 movements of long period (LP) have been entered. In the station of CONE, located in the northeastern flank of the cone, a high number of signals of rock falls is registered which come from the front of the lava flow that descends by that sector (32 signals per hour). The volcano has remained dimmed and in the morning today one slight rain was registered. They have not registered lahars.

Reventador is the most frequently active of a chain of Ecuadorian volcanoes in the Cordillera Real, well east of the principal volcanic axis. The forested, dominantly andesitic Volcán El Reventador stratovolcano rises to 3562 m above the jungles of the western Amazon basin. A 4-km-wide caldera widely breached to the east was formed by edifice collapse and is partially filled by a young, unvegetated stratovolcano that rises about 1300 m above the caldera floor to a height comparable to the caldera rim. Reventador has been the source of numerous lava flows as well as explosive eruptions that were visible from Quito in historical time. Frequent lahars in this region of heavy rainfall have constructed a debris plain on the eastern floor of the caldera. The largest historical eruption at Reventador took place in 2002, producing a 17-km-high eruption column, pyroclastic flows that traveled up to 8 km, and lava flows from summit and flank vents.

The official colour of the volcanic alarm light remains on ORANGE

[Shammu]

Mt. ETNA

As of the 3rd of December it has been reported by INGV-CT that normally December should be one month of festivals, or mix happiness in family, the gifts of end of the year and the approach of New Year's Day that we wish and hope for all happiness and good health. This morning there is bad news coming from Mt. Etna. Photograher/ExplorerThomas Reichart had disappeared for Saturday after midday on Mt. Etna. Its lifeless body was found this morning in Valle del Bove in the zone of the hornitos to 2750 metres after having seemed that he slipped on ice into a rather abrupt place. Roof of bad luck and this after the newspaper Sicilia, Thomas sent a sms (Help, Thomas) to Boris Behnnke who work for INGV-CT. Boris waned to help but the bad weather conditions did not allow to find him before this morning. Thomas also had this passion of Mt. Etna and rather often went to photograph and film the eruptions of Mt. Etna.

Mt. Etna, towering above Catania, Sicily's second largest city, has one of the world's longest documented records of historical volcanism, dating back to 1500 BC. Historical lava flows of basaltic composition cover much of the surface of this massive volcano, whose edifice is the highest and most voluminous in Italy. The Mongibello stratovolcano, truncated by several small calderas, was constructed during the late Pleistocene and Holocene over an older shield volcano. The most prominent morphological feature of Etna is the Valle del Bove, a 5 x 10 km horseshoe-shaped caldera open to the east. Two styles of eruptive activity typically occur at Mt. Etna. Persistent explosive eruptions, sometimes with minor lava emissions, take place from one or more of the three prominent summit craters, the Central Crater, NE Crater, and SE Crater (the latter formed in 1978). Flank vents, typically with higher effusion rates, are less frequently active and originate from fissures that open progressively downward from near the summit (usually accompanied by strombolian eruptions at the upper end). Cinder cones are commonly constructed over the vents of lower-flank lava flows. Lava flows extend to the foot of the volcano on all sides and have reached the sea over a broad area on the SE flank.

The volcano Mt. Etna is currently at the ORANGE
~~~~~~~~

RABAUL

As of the 4th of December, the Rabaul Volcano Observatory (RVO) has reported that during 21-27 November light gray ash plumes and white steam plumes from Rabaul caldera's Tavurvur cone rose to an altitude of 1.7 km (5,600 ft) a.s.l. and drifted SE, S, SW, and W. Ashfall was reported in areas downwind. Incandescence from the vent was observed, and rumbling and roaring noises were reported on some days. Explosions or forceful emissions sometimes ejected incandescent lava fragments. Based on analysis of satellite imagery, the Darwin VAAC reported that during the 30th of November-the 1st of December ash plumes rose to an altitude of 3 km (10,000 ft) a.s.l. and drifted W and WSW.

The low-lying Rabaul caldera on the tip of the Gazelle Peninsula at the NE end of New Britain forms a broad sheltered harbour utilised by what was the island's largest city prior to a major eruption in 1994. The outer flanks of the 688-m-high asymmetrical pyroclastic shield volcano are formed by thick pyroclastic-flow deposits. The 8 x 14 km caldera is widely breached on the east, where its floor is flooded by Blanche Bay and was formed about 1400 years ago. An earlier caldera-forming eruption about 7100 years ago is now considered to have originated from Tavui caldera, offshore to the north. Three small stratovolcanoes lie outside the northern and NE caldera rims of Rabaul. Post-caldera eruptions built basaltic-to-dacitic pyroclastic cones on the caldera floor near the NE and western caldera walls. Several of these, including Vulcan cone, which was formed during a large eruption in 1878, have produced major explosive activity during historical time. A powerful explosive eruption in 1994 occurred simultaneously from Vulcan and Tavurvur volcanoes and forced the temporary abandonment of Rabaul city.

The Rabaul volcano is currently at the ALERT LEVEL 2
~~~~~~~~~~~

KILAUEA

As of the 4th of December, it has been reported to INTLVRC direct from the Hawaiian Volcano Observatory (HVO), that there have been no significant changes. Sulfur dioxide emission rates from the Halema`uma`u and the Pu`u `O`o vents remain high. Tephra production from the Halema`uma`u vent remains a small fraction of east rift zone lava production. At the east rift eruption site, lava flows through tubes to the ocean; surface flows are active near the base of the pali.

Last 24 hours at Kilauea summit: Yesterday, southerly winds moved the plume northward in the morning, shifting to northwestward in the afternoon; the HVO, Kilauea Visitors Center, the Volcano Golf Course, and Kulani Prison SO2 sensors all recorded high concentrations mid-afternoon yesterday. Glow, or indirect incandescence, from the vent was recorded intermittently by the webcam last night. Weak winds this morning are allowing the plume to rise nearly vertically from the vent and stagnate in the summit area producing low SO2 concentrations. This morning, the plume must also be moving northward resulting in very high SO2 concentrations at Kulani Prison as of this posting. Sulfur dioxide emission rates remain elevated and variable. The most recent average measurement was 500 tonnes/day on November 26th, still elevated above the 2003-2007 average rate of 140 tonnes/day. Measurements will resume when moderate trade winds return. Variable but small amounts of tephra, mostly ash-sized spatter, continue to be produced and deposited downwind of the vent. The collectors south of the vent received very little fallout. The southerly winds are allowing occasional views from the south into the vent; bright glow was seen from that vantage with somewhat different sounds, possibly from different acoustics; rockfalls were still heard. The network of tiltmeters within the caldera recorded minor oscillations with no significant overall change. The GPS receiver networks (less sensitive than tiltmeters) recorded neither extension nor contraction across the caldera since mid-November; overall, there has been almost 3 cm of contraction in the past 3 months. Seismic activity continues to be focused on the south caldera; tremor levels remain at moderate values. A total of 7 earthquakes were located beneath Kilauea or nearby, with 4 beneath the south caldera and 2 on south flank faults.

Last 24 hours in the middle east rift zone vents and flow field: Magma continues to degas through Pu`u `O`o Crater. The most recent sulfur dioxide emission rate measurement was 1,300 tonnes/day measured on November 25th compared to the 2003-2007 average of about 1,700 tonnes/day for this vent. No incandescence was observed within the crater overnight. Pu`u `O`o continues to deflate/collapse. The tiltmeter on the north side of Pu`u `O`o recorded minor oscillations without much net change. GPS stations spanning the crater (less sensitive than tiltmeters) recorded almost 4 cm of contraction over the past 3 months. Seismic tremor levels near Pu`u `O`o and the TEB vent remain at low values. Lava from the TEB vent and the rootless shield complex continues to flow through tubes to the ocean. Yesterday afternoon, the Waikupanaha ocean entry and surface flows in the western branch were active. Overnight, no incandescence was seen in the area extending from the east rift eruption site to the top of the pali. GOES-WEST imagery showed persistent thermal anomalies, suggesting continued surface flow activity overnight. This morning, CD officials report continuing ocean entry activity and dim glow from the western branch of the TEB flow early.

The Kilauea volcano is currently at the ORANGE

[Shammu]

ARENAL

As of the 1st of December, the Observatorio Vulcanológico y Sismológico de Costa Rica reported that conical Volcán Arenal is the youngest stratovolcano in Costa Rica and one of its most active. The 1670-m-high andesitic volcano towers above the eastern shores of Lake Arenal, which has been enlarged by a hydroelectric project. Arenal lies along a volcanic chain that has migrated to the NW from the late-Pleistocene Los Perdidos lava domes through the Pleistocene-to-Holocene Chato volcano, which contains a 500-m-wide, lake-filled summit crater. The earliest known eruptions of Arenal took place about 7000 years ago, and it was active concurrently with Cerro Chato until the activity of Chato ended about 3500 years ago. Growth of Arenal has been characterized by periodic major explosive eruptions at several-hundred-year intervals and periods of lava effusion that armor the cone. Arenal's most recent eruptive period began with a major explosive eruption in 1968. Continuous explosive activity accompanied by slow lava effusion and the occasional emission of pyroclastic flows has occurred since then from vents at the summit and on the upper western flank and continues to this day.

Once locally known as Cerro Arenal (i.e. Mount Arenal) it was presumed extinct until July 29, 1968 when an earthquake caused it to erupt after approximately 400 years of dormancy. The eruption wiped out the town of Arenal and killed 87 people. It lasted for several days, and during that time destroyed crops, property, livestock, and forests. 15 square kilometers were buried and the explosion affected over 232 square kilometers. The eruption caused three new and active craters to form. Before the eruption, there was a wide variety of plant and wildlife on the mountain. It has been active since the explosion and can be reported to have minor eruptions every 5-10 minutes.

The Arenal Volcano, in Spanish Volcán Arenal, is an active andesitic stratovolcano in north-western Costa Rica (10.5N, 84.7W), around 90 km north-west of San José, in the province of Alajuela. Recognised as a volcano since the 19th century, it was known by foreign investigators as "Volcan Costa Rica, Rio Frio", "Canastos" Volcano and "Cerro de los Guatusos". Arenal is the youngest and most active of all the mountains in Costa Rica. Scientists have been able to date it back to more than 4000 years ago. The area remained largely unexplored until 1937, when a documented expedition took place to reach the summit.

The Current Colour Code for Arenal is ORANGE
~~~~~~~~~

YASUR

As of the 1st of December, mainly from reports from colleague, John Seach of Australia, reports that Yasur is still currently erupting. Strombolian and mild Vulcanian eruptions continue at Yasur volcano. Three main active vents are visible inside the summit crater. Incandescent lava explosions reached 250 m above the crater, accompanied by loud explosions. Projectiles were observed falling on the crater rim, 170 m from the vents. Yasur volcano, in southern Vanuatu continues to be one of the world's most active volcanoes. The volcano continues to erupt many times per hour as it has for at least 800 years. Yasur has been called the "Lighthouse of the Pacific" because of the regular Strombolian eruptions visible from sea. Warning: Approaching the active crater at Yasur volcano is dangerous at any time ! Observers are at risk from projectiles, toxic gas and avalanches.

Projectile ejection Yasur volcano has not produced a large destructive eruption historically. There is no indication that a large eruption will occur in the near future at Yasur volcano. Magma chamber inflation is currently being accommodated by the volcano. The largest reasonable level of activity expected is the ejection of bombs 3-4 km from the vent, and pyroclastic flows threatening low lying areas near the volcano. This type of activity would pose a danger to nearby villages. Ground deformation Yasur volcano has the second greatest level of ground uplift in the world. Since 1000 AD there has been a yearly average uplift of 149 mm. This is only beaten by Iwo Jima volcano in Japan with 200 mm uplift per year since 1200 AD. Tsunami Volcanic and tectonic earthquakes, and landslides may result in the production of tsunamis which may threaten coastal populations. Flooding Lake Siwi broke through its natural dam in 2002 flooding Sulphur Bay Village and destroying houses. Landslides Landslide and debris flow pose significant risks to the surrounding population. Uplift of the caldera creates unstable ground, combined with the deposition of unstable ash and cinders. Ashfall Periods of strong volcanic activity may cause ashfall over large areas of Tanna Island. Ashfall can damage crops, cause roofs to collapse, and result in mudflows after rain. Gas samples collected from the plume crossing Yasur crater rim in 1988 contained SO2 and HCl gases at concentrations between 3 and 9 ppm. This is a hazardous level of gas. This level of SO2 causes a decrease in lung function and immediate irritation of eyes nose and throat. Lava Flow Lava flows occur infrequently at Yasur volcano.

Yasur, the best-known and most frequently visited of the Vanuatu volcanoes, has been in more-or-less continuous strombolian and vulcanian activity since Captain Cook observed ash eruptions in 1774. Yasur, located at the SE tip of Tanna Island, is a mostly unvegetated 361-m-high pyroclastic cone with a nearly circular, 400-m-wide summit crater. Yasur is largely contained within the small Yenkahe caldera and is the youngest of a group of Holocene volcanic centres constructed over the down-dropped NE flank of the Pleistocene Tukosmeru volcano. Active tectonism along the Yenkahe horst accompanying eruptions of Yasur has raised Port Resolution harbour more than 20 m during the past century.

The Current Colour Code for Yasur is ALERT LEVEL 3
~~~~~~~~~

STROMBOLI

As of the 1st of December, the Instituto Nazionale di Geofisica e Vulcanologia - Sezione di Catania has reported that eruptions still continue at Stromboli. As of September 23rd, Hans Aeschlimann recorded moderate to strong activity on Pizzo.

Spectacular incandescent nighttime explosions at Stromboli volcano have long attracted visitors to the "Lighthouse of the Mediterranean." Stromboli, the NE-most of the Aeolian Islands, has lent its name to the frequent mild explosive activity that has characterised its eruptions throughout much of historical time. The small, 924-m-high island of Stromboli is the emergent summit of a volcano that grew in two main eruptive cycles, the last of which formed the western portion of the island. The Neostromboli eruptive period from about 13,000 to 5000 years ago was followed by formation of the modern Stromboli edifice. The active summit vents are located at the head of the Sciara del Fuoco, a prominent horseshoe-shaped scarp formed about 5000 years ago as a result of the most recent of a series of slope failures that extend to below sea level. The modern volcano has been constructed within this scarp, which funnels pyroclastic ejecta and lava flows to the NW. Essentially continuous mild strombolian explosions, sometimes accompanied by lava flows, have been recorded at Stromboli for more than a millennium.

The Current Colour Code for Stromboli is ORANGE

[Shammu]

Mt. EREBUS

As of the 1st of December, the Mt. Erebus Volcano Observatory (MEVO) reports that Mt. Erebus continues to have a persistent convecting phonolite lava lake, persistent low-level eruptive activity. It is one of Earth's few long-lived lava lakes. It is the most active volcano in Antarctica. Lavas and bombs contain large (<10 cm) phenocrysts (crystals) of anorthoclase feldspar. Lava flows of more viscous phonotephrite, tephriphonolite and trachyte are erupted after the basanites.

CAVEAT: Despite the database of information on the geology of Mt. Erebus, there is still much to be learned about the volcano. The relative lack of knowledge becomes apparent when Mt. Erebus is stacked up against other active volcanoes of the world. There are many reasons for this comparative lack of knowledge, including the scarcity of rock exposures due to snow and ice cover, the remoteness of the volcano, the extreme environment, the brief field season (<6 weeks per year) and its non-threatening nature (i.e. no large populations are in jeopardy because of Mt. Erebus, unlike Vesuvius in Italy or Popocatepetl in Mexico).

Despite the above factors limiting the Mt. Erebus knowledge base, clearly much has been learned about the volcano over the past 25+ years. Nearly all exposed lava flow sets on Mt. Erebus have been physically sampled. Nearly all of these have been examined petrographically and petrologically. The summit lava flows on Mt. Erebus have been extensively mapped and dated by the 40Ar/39Ar method. The flank flows have been mapped in less detail, but many have also been dated. Tephra from Mt. Erebus has been found in glaciers on the volcano, mapped, geochemically examined and dated. The morphological characteristics of the edifice have been combined with the geochronological data to provide an evolutionary history of Mt. Erebus. And the physical and eruptive characteristics of the summit lava lake has been observed nearly every year for the past 25 years.

Mt. Erebus, Ross Island, Antarctica is the world's southern-most active volcano. Discovered in 1841 by James Ross, it is one of only a very few volcanoes in the world with a long-lived (decades or more) lava lake. Scientific research, sponsored by the U.S. National Science Foundation (NSF) since began the early 1970ís had included basic study of the petrology and geophysics of the volcano, the eruptive history, activity and degassing behavior of the lava lake, and the overall impact of the volcano on the Antarctica and global environment.

The Current Colour Code for Mt. Erebus is ORANGE

[Shammu]

 Yellowstone quakes raise explosion fears

    * 15:36 06 January 2009 by David Shiga

Hundreds of earthquakes rippled through Yellowstone National Park, Wyoming, in late December and early January, prompting fears that the shaking might trigger dangerous steam explosions.

Magma and steam permeate the rock beneath Yellowstone, and the motion of these fluids is thought to be responsible for the thousands of small earthquakes recorded in and around the park each year.

With magnitudes between 0 and 2, these everyday quakes are usually small enough to go unnoticed by people on the surface.

But beginning on 26 December, a much more powerful swarm of quakes shook the area. The strongest were easily felt by visitors and park staff, including one with a magnitude of 3.9 that unleashed hundreds of times the energy of a magnitude 2.

These were still too small to cause damage directly, but there were worries that the vibrations might cause pent up steam to burst through the surface with explosive force.
Crater evidence

Yellowstone, which sits atop a supervolcano, is pockmarked with craters thought to have been produced this way, and geologists estimate an explosion big enough to make a 100-metre crater happens there about every 200 years.

At the time of writing, though, the swarm was subsiding with no reports of such an event. "It hasn't stopped, but it has reduced markedly in the last couple of days," said Robert Smith of the University of Utah on Monday.

There are no signs of any volcanic eruptions on the way, either, said Smith, who monitors Yellowstone's geologic activity.

The quakes appear to be concentrated along a fault beneath the park. Further analysis should reveal whether they were triggered by forces associated with the fault, activity of hot fluids beneath the surface, or some other cause, he says.

Yellowstone quakes raise explosion fears

[Shammu]

Now as promised earlier...............

YELLOWSTONE CALDERA - UNITED STATES (Wyoming)

As of the 9th of January, the Yellowstone Volcano Observatory (YVO), reported that the Yellowstone Lake Earthquake Swarm Summary as of 8 January 2009is as follows: Seismic activity at Yellowstone Lake in Yellowstone National Park increased in late December 2008. As of January 6, 2009, the seismic activity has markedly decreased (Listen to a podcast with YVO's Scientist-in-Charge about the recent swarm). It is possible that the swarm has ended, although a return of activity may occur as previous Yellowstone swarms of this size have lasted for tens of days to many weeks. Swarms are common at Yellowstone. The last notable swarm occurred in 2004.

Seismologists continue to review the earthquakes. About 900 earthquakes occurred between Dec. 26th, 2008 and Jan. 8th, 2009 in the Yellowstone Lake area. Five hundred of the earthquakes (including all greater than magnitude 2.0) have been reviewed by seismologists. There were 111 earthquakes with magnitudes greater than 2.0 (>M2.0)and 18 earthquakes >M3.0. About 400 smaller earthquakes have yet to be reviewed. The largest earthquake during the swarm was a magnitude 3.9 on Sunday, December 28th, 2008. One of the analyses seismologists use to talk about earthquakes and swarms is the cumulative seismic moment, which is a measure of the earthquake energy. The cumulative moment (the energy from all the analysed earthquakes in the swarm) for the Yellowstone Lake Swarm is equal to the energy of a single magnitude 4.5 earthquake. Depths for shallow earthquake hypocentres (the point within the earth where an earthquake rupture starts) are difficult to determine accurately unless the seismic stations are spaced much more closely than those in the Yellowstone Seismic Network. The best located earthquakes have hypocentres (depths) of 3 to 10 km (1.8 to 6.0 miles). From Dec. 26 through Jan 2, the hypocentres appear to have migrated northwards, starting southeast of near Stevenson Island, with many of the latest events occurring near Fishing Bridge.

Swarms are normal at Yellowstone. The recent swarm is well above typical activity at Yellowstone. Nevertheless it is not unprecedented during the last 40 years of monitoring. Earthquake swarms within the Yellowstone caldera are typical, with magnitudes occasionally ranging above 4.0. The 1985 swarm on the northwest rim of the caldera lasted for three months, with earthquakes up to M4.9 and over 3000 total events recorded. The magnitudes of earthquakes in this swarm range from zero to 3.9. Earthquakes with magnitudes less than 3.4 are generally not felt by people unless they are very shallow and you are standing very close to the epicentre (point on the earth's surface above the hypocentre). For perspective, earthquakes of magnitude 3.4 to 4.5 are often felt and there were multiple reports of felt earthquakes during this swarm. A magnitude 5 or greater is generally required to produce damage to buildings or other structures.

New equipment allowed UUSS to monitor the swarm. Improved volcano and seismic monitoring at Yellowstone gives us a greater ability to locate earthquakes, understand their source process and identify anomalous sources of seismic activity. New equipment including precise measurements of ground motion by GPS receivers and borehole strainmeters provided by the National Science Foundation's EarthScope and Continental Dynamics Program have been used extensively during the last week of intense earthquake activity. Ground motions accompanying the swarm, from the GPS instruments will take two or more weeks to fully process. It is worth noting that in 2004 the Yellowstone caldera began a period of accelerated uplift measured by GPS instruments that was as large as 7 cm/yr (2.7 inches/yr), three times as fast as recorded in the recorded history but has now reduced to about a maximum rate of 4 cm/yr. Scientists have modeled this deformation as due to magmatic recharge of the Yellowstone magma chamber at a depth of ~10 km (6 miles). The area of the swarm is on the eastern side of the uplift area.

There are several causes for earthquakes. Earthquakes at Yellowstone are caused by a combination of geological factors including: 1) regional stress associated with normal faults (those where the valleys go down relative to the mountains) such as the nearby Teton and Hebgen Lake faults, 2) magmatic movements at depth (>7 kms or 4 miles), and 3) hydrothermal fluid activity caused as the groundwater system is heated to boiling by magmatic heat. At this time, no one has noted any anomalous changes in surface discharges (hot springs, gas output, etc.).

YVO staff from the USGS, University of Utah and Yellowstone National Park continue to carefully review all data streams that are recorded in real-time. At this time, there is no reason to believe that magma has risen to a shallow level within the crust or that a volcanic eruption is likely. The USGS Volcano alert level for Yellowstone Volcano remains at Normal/Green. Yellowstone National Park is evaluating infrastructure near the north end of Yellowstone Lake to assess if any damage has occurred to facilities. Winter visitor activities and staff operations have not been impacted and continue as normal.

Data are transmitted to the University in real-time by radio and satellite links from a network of 28 seismographs in the Yellowstone area and are available on the web. Seismologists continue to analyze data from this swarm of earthquakes and provide updates to the NPS and USGS and to the public via the following web pages.
Information on U.S. earthquake activity including Yellowstone can be viewed at the U.S. Geological Survey web site: http://earthquake.usgs.gov/eqcenter/recenteqsus/
Information on earthquakes can also be viewed at the University of Utah Seismograph Stations web site: http://www.seis.utah.edu/.
Seismographic recordings from Yellowstone seismograph stations can be viewed online at: http://www.quake.utah.edu/helicorder/heli/yellowstone/index.html.

The colour code at Yellowstone is currently at GREEN

******** Pro 10.7 is not capable of forecasting a supervolcano to erupt. 

[Shammu]

SHISHALDIN - ALEUTIAN IS.

As of the 9th of January, the Alaska Volcano Observatory (AVO) has reported that a weak thermal anomaly persists in satellite views of Shishaldin Volcano. Seismicity remains unchanged. Yesterday, AVO received a pilot report and observations from Cold Bay describing a vigorous vapor plume from the summit. This activity is considered typical for Shishaldin.

The beautifully symmetrical volcano of Shishaldin is the highest and one of the most active volcanoes of the Aleutian Islands. The 2857-m-high, glacier-covered volcano is the westernmost of three large stratovolcanoes along an E-W line in the eastern half of Unimak Island. The Aleuts named the volcano Sisquk, meaning "mountain which points the way when I am lost." A steady steam plume rises from its small summit crater. Constructed atop an older glacially dissected volcano, Shishaldin is Holocene in age and largely basaltic in composition. Remnants of an older ancestral volcano are exposed on the west and NE sides at 1500-1800 m elevation. Shishaldin contains over two dozen pyroclastic cones on its NW flank, which is blanketed by massive aa lava flows. Frequent explosive activity, primarily consisting of strombolian ash eruptions from the small summit crater, but sometimes producing lava flows, has been recorded since the 18th century.

The colour code at Shishaldin is currently at YELLOW.
~~~~~~~~~~~~~~~~~~~~~.

CLEVELAND - ALEUTIAN IS.

As of the 6th of January, the Alaska Volcano Observatory (AVO) has reported that a minor thermal anomaly observed in satellite views of the summit this morning. No other reports of activity have been received. Cleveland is not seismically monitored; satellite data and pilot reports are the primary source of information.

Beautifully symmetrical Mt. Cleveland stratovolcano is situated at the western end of the uninhabited, dumbbell-shaped Chuginadak Island. It lies SE across Carlisle Pass strait from Carlisle volcano and NE across Chuginadak Pass strait from Herbert volcano. Cleveland is joined to the rest of Chuginadak Island by a low isthmus. The 1730-m-high Mt. Cleveland is the highest of the Islands of the Four Mountains group and is one of the most active of the Aleutian Islands. The native name for Mt. Cleveland, Chuginadak, refers to the Aleut goddess of fire, who was thought to reside on the volcano. Numerous large lava flows descend the steep-sided flanks of the volcano. It is possible that some 18th-to-19th century eruptions attributed to Carlisle should be ascribed to Cleveland (Miller et al., 1998). In 1944 Cleveland produced the only known fatality from an Aleutian eruption. Recent eruptions from Mount Cleveland have been characterized by short-lived explosive ash emissions, at times accompanied by lava fountaining and lava flows down the flanks.

The colour code at Cleveland is currently at YELLOW.
~~~~~~~~~~~~~~~

REDOUBT - UNITED STATES (Alaska)

As of the 4th of January, the Alaska Volcano Observatory (AVO), reported that seismic activity at Redoubt remains at low levels. Nothing unusual was seen in clear views of the volcano from satellite. No reports of unusual activity were received.

Redoubt is a 3108-m-high glacier-covered stratovolcano with a breached summit crater in Lake Clark National Park about 170 km SW of Anchorage. Next to Mt. Spurr, Redoubt has been the most active Holocene volcano in the upper Cook Inlet. The volcano was constructed beginning about 890,000 years ago over Mesozoic granitic rocks of the Alaska-Aleutian Range batholith. Collapse of the summit of Redoubt 10,500-13,000 years ago produced a major debris avalanche that reached Cook Inlet. Holocene activity has included the emplacement of large clay-rich lahars, one of which dammed Lake Crescent on the south side and reached Cook Inlet about 3500 years ago. Eruptions during the past few centuries have affected only the Drift River drainage on the north. Historical eruptions have originated from a vent at the north end of the 1.8-km-wide breached summit crater. The 1989-90 eruption of Redoubt had severe economic impact on the Cook Inlet region and affected air traffic far beyond the volcano.

The colour code at Redoubt is currently at YELLOW.

[Shammu]

KARANGETANG

As of the 7th of December, the Volcano Discovery team's tour guide, Doni, has reported that strong Strombolian eruptions at the Karangetang volcano. The cone is covered by hot lapilli and ash plumes can be seen. Strombolian eruptions can be seen every 10 - 15 minute. Also Volcanian eruptions. Also, CVGHM reported that on the 28th of November seismicity from Karangetang increased. On the 29th of November incandescent rockslides from the main crater traveled 250-1,000 m S and W.

Karangetang a.k.a (Api Siau) volcano lies at the northern end of the island of Siau, north of Sulawesi. The 1784-m-high stratovolcano contains five summit craters along a N-S line. Karangetang is one of Indonesia's most active volcanoes, with more than 40 eruptions recorded since 1675 and many additional small eruptions that were not documented in the historical record (Catalog of Active Volcanoes of the World: Neumann van Padang, 1951). Twentieth-century eruptions have included frequent explosive activity sometimes accompanied by pyroclastic flows and lahars. Lava dome growth has occurred in the summit craters; collapse of lava flow fronts has also produced pyroclastic flows.

The Current Colour Code for Karangetang is currently at the ALERT LEVEL 3
~~~~~~~~~~~~~

BARREN IS.

As of the 11th of December, the Global Volcanism Network (GVN) reported that the Darwin VAAC reported that during 7-8 December pilots observed lava flows on Barren Island; ash plumes were not present. Thermal anomalies were detected on satellite imagery.

Barren Island, a possession of India in the Andaman Sea about 135 km NE of Port Blair in the Andaman Islands, is the only historically active volcano along the N-S-trending volcanic arc extending between Sumatra and Burma (Myanmar). The 354-m-high island is the emergent summit of volcano that rises from a depth of about 2,250 m. The small, uninhabited 3-km-wide island contains a roughly 2-km-wide caldera with walls 250-350 m high. The caldera, which is open to the sea on the W, was created during a major explosive eruption in the late Pleistocene that produced pyroclastic-flow and -surge deposits. The morphology of a fresh pyroclastic cone that was constructed in the centre of the caldera has varied during the course of historical eruptions. Lava flows fill much of the caldera floor and have reached the sea along the western coast during historical eruptions.

The Current Colour Code for Barren Is. is currently at the ORANGE
~~~~~~~~~~~~

Volcano: CHAITEN

As of the 27th of December, the Government of Chile has announced that the area surrounding Chaiten volcano, in Chile is still not safe, following the large May 2008 eruption. A decision regarding the future of of Chaiten town will be made in coming days. The volcano, only 10 km from the town, started erupting on 2nd May, after being dormant for thousands of years, forcing the evacuation of about 7,000 residents. The government has not dismissed the possibility of relocating Chaiten town and making the whole area a no-go zone for years to come, but many locals have said they want to return to their homes. The latest report indicates the volcano is as dangerous as before, and the news is still not good. Dome growth continues at the volcano. The old caldera is almost completely filled by the new dome. This creates an increased danger from the volcano, and future dome collapse may send pyroclastic flows down the flanks of the volcano.

On the 25th of December, the Global Volcanism Network (GVN) reported that Chile’s Chaitén Volcano remained active in mid-December 2008, releasing plumes of ash and/or steam. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured the above image on December 14, 2008. In this image, a faint plume appears blowing away from the volcano, toward the southeast. After lying dormant for more than 9,000 years, Chaitén Volcano violently erupted in May 2008, smothering much of the region’s vegetation in ash, blocking river channels, and threatening lahars— mudflows of volcanic material. This image catches the volcano emitting a relatively mild plume, compared to some of its activity earlier in 2008. Chaitén is a caldera volcano. This type of volcano forms when the magma chamber completely empties during an eruption, causing the summit to collapse and create a circular depression.

The Current Colour Code for Chaiten is currently at the ORANGE

[Shammu]

SUWANOSE-JIMA

As of the 25th of December, the Japan Meteorlogical Agency (JMA) has reported that based on information from JMA, the Tokyo VAAC reported that during 17 and 19-20 December explosions or eruptions from Suwanose-jima produced plumes to an altitude of 1.5 km (5,000 ft) a.s.l. Plumes drifted E on 17 and 19 December.

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 E 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 (also called Otake), 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.(JMA)

The Current Colour Code for Suwanose-Jima is currently at the YELLOW
~~~~~~~~~~~~

GALERAS

As of the 25th of December, the Observatory Vulcanológico and Sismológico de Pasto - INGEOMINAS, informs that the associate seismic activity with processes related to flowed sources of movement persists of inside the volcanic system, that in surface is reflected with the degassing of the same. Generally, the total seismicity registered diminution with respect to the levels reported in the last weeks; nevertheless, a significant increase in the occurrence of the episodes of tremor is emphasised that by their characteristics, are associated with the continuity in the process of intrusion of magmatic material. This activity was associate also with the registry of an earthquake of located fracture of magnitude 2 towards the western flank of the main crater. The climatic conditions allowed to observe volcanic gas discharge on days 17 and 20 of December, with smaller heights of column of 500 m on the top and preferential dispersion towards the south by action of winds. During this week, the value of sulphur dioxide (SO2) measured in the stations located in the western sector was smaller of 200 tonnes, which could be influenced by the direction of gases in opposed direction of the one of location of the stations and by the adverse conditions of climate. An effective reduction of the rates of emission of this gas of the volcano does not discard either. Stays the general evaluation of the phenomenon under which a magmatic body in surfaces is demonstrated, that a process fluctuating of growth and degassing maintains. That degassing could see affected when a phase of cooling, crystallisation and solidification of the material of the dome is marked. The presence of that magmatic material in surface, in the form of dome and in gradual growth, deserves special attention to the evolution of the process, without so far it implies a change in the activity level.

The Current Colour Code for Galeras is currently at LEVEL III
~~~~~~~~~~

NEVADO del HUILA

As of the 25th of December, the National Institute Of Sismología, Volcanology, Meteorology And Hidrologia, INGEOMINAS reported that in the present week a total of 924 seismic events was registered. Of them, 446 are related to fracturing of rock, 385 with the dynamics of flowed within the volcanic conduits, 15 hybrids and 78 pulses of tremor of low magnitude Wednesday, the 17th and Thursday the 18th of December two movable measures of SO2 were realised on the Pan-American highway Cali - Popayán. These measures were characterised to throw losses SO2 concentrations, obtaining themselves 496 flows of tonnes/day and 322 tonnes/day, in columns with preferential dispersions towards the sectors southwest and northwestern of the volcanic complex, respectively. Thursday the 18th of December a fixed station settled in the municipality of Caloto (the Cauca) to realise continuous measurements of the SO2 emitted by the Snow-covered volcano of the Huila. From Friday the 19th of December, they have available in the page WEB of the Observatory Vulcanológico and Sismológico de Popayán (http://intranet.ingeominas.gov.co/popayan), images in almost real time the volcanic complex. The obtained images show continuous degassing of the system, demonstrated by the presence of gas columns of whitish colouration, that do not surpass 2000 m of altitude. The prevailing climatic conditions in the zone disabled the accomplishment of overflights to the high part of the volcanic complex. The location of a dome body in surface deserves a special pursuit, due to the different scenes that can be triggered; new overflights are planned to observe their evolution in surface.

The Current Colour Code for Nevado del Huila is currently at ORANGE

[Shammu]

PACAYA

As of the 24th of December, the National Institute Of Sismología, Volcanology, Meteorology And Hidrologia, (INSIVUMEH) has reported that for Atmospheric Conditions: Cleared. Pluvial Precipitation: 0.0 mm. Wind speed: 40.0 km/hr. Direction: South & Southwest. Activity: Continuous in their state of activity with degassing on the crater, the lava flows stays that varies between 3 and 4 in sporadic form and that reaches between 100 to 200 m of length. Constant plume with a southwestern direction and a route of up to 400 m, that stays low and it dissolves by action of the wind. At night it is possible to both observe the incandescence on íntercrater cones. Seismic activity of with events type "B" generated by Strombolian explosions.

The eruptions from Pacaya, one of Guatemala's most active volcanoes, are frequently visible from Guatemala City, the nation's capital. Pacaya is a complex basaltic volcano constructed just outside the southern topographic rim of the 14 x 16 km Pleistocene Amatitlán caldera. A cluster of dacitic lava domes occupies the southern caldera floor. The post-caldera Pacaya massif includes the Cerro Grande lava dome and a younger volcano to the SW. Collapse of Pacaya volcano about 1100 years ago produced a debris-avalanche deposit that extends 25 km onto the Pacific coastal plain and left an arcuate somma rim inside which the modern Pacaya volcano (MacKenney cone) grew. A subsidiary crater, Cerro Chino, was constructed on the NW somma rim and was last active in the 19th century. During the past several decades, activity at Pacaya has consisted of frequent strombolian eruptions with intermittent lava flow extrusion that has partially filled in the caldera moat and armored the flanks of MacKenney cone, punctuated by occasional larger explosive eruptions that partially destroy the summit of the cone.

The Current Colour Code for Pacaya is currently at ORANGE
~~~~~~~~~~~~~~~

FUEGO

As of the 24th of December, the National Institute Of Sismología, Volcanology, Meteorology And Hidrologia, (INSIVUMEH) has reported that for Atmospheric Conditions: Cleared. Pluvial Precipitation: 0.0 mm. Wind speed: 18.0 km/hr. Direction: South & Southwest. Activity: Grayish white fumaroles in a southwestern direction. Gradual increases in the explosions are observed having arrived to enter themselves until moment 15 in the last 24 hours as they have been 11 weak and only 1 moderate, bringing about ash expulsion and gases until heights of 1000 metres, generating the ash fall (up to 2 millimeters of thickness) in the communities of Panimache, Sangre de Cristo, Finca Palo Verde and part of Yepocapa, as well as near the Taniluya river. In their majority the explosions are generating rumblings and shock waves that make vibrate ceilings and windows of houses in a radius of 8 kilometres. In the Ash-gray ravine where the lava flow stays of 150 metres in length constantly are occurring avalanches of incandescent blocks that arrive at the vegetation.

The 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 3763-m-high Fuego and its twin volcano to the north, Acatenango. Construction of Meseta volcano dates back to about 230,000 years and continued until the late Pleistocene or early Holocene. Collapse of Meseta volcano may have produced the massive Escuintla debris-avalanche deposit, which extends about 50 km onto the Pacific coastal plain. Growth of the modern Fuego volcano followed, continuing the southward migration of volcanism that began at Acatenango. In contrast to the mostly andesitic Acatenango volcano, eruptions at Fuego have become more mafic with time, and most historical activity has produced basaltic rocks. 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 Current Colour Code for Fuego is currently at ORANGE
~~~~~~~~~~~~~~

SANTA MARIA

As of the 24th of December, the National Institute Of Sismología, Volcanology, Meteorology And Hidrologia, (INSIVUMEH) has reported that for Atmospheric Conditions: Cleared. Pluvial Precipitation: 0.0 mm. Wind speed: 15.0 km/hr. Direction: West & Southwest. Activity: Activity of weak explosions with degassing especially between 0530 and 0600 hours, generation of pyroclastic flows that descended by the skirts of the volcano, rising columns of gray ash to 800 metres on the crater of the Cono Caliente, dispersing to the South, Southwest, esteem that the ash to disperse itself to tens of kilometres due to the wind speed and to the fineness of its texture.

The symmetrical, forest-covered Santa María volcano is one of the most prominent of a chain of large stratovolcanoes that rises dramatically above the Pacific coastal plain of Guatemala. The 3772-m-high stratovolcano has a sharp-topped, conical profile that is cut on the SW flank by a large, 1.5-km-wide crater. The oval-shaped crater extends from just below the summit of Volcán Santa María to the lower flank and was formed during a catastrophic eruption in 1902. The renowned plinian eruption of 1902 that devastated much of SW Guatemala followed a long repose period after construction of the large basaltic-andesite stratovolcano. The massive 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, the most recent of which is Caliente. Dome growth has been accompanied by almost continuous minor explosions, with periodic lava extrusion, larger explosions, pyroclastic flows, and lahars.

The Current Colour Code for Santa Maria is currently at ORANGE