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Archive for the ‘Redoubt’ Category

VolcanoWatch [27 May 2009]

Posted by feww on May 28, 2009

Volcanic Activity Report: 20 May – 26 May 2009

Source: Global Volcanism program (GVP) – SI/USGS Weekly Volcanic Activity Report

New activity/unrest:

Redoubt Activity – Color Code ORANGE : Alert Level WATCH


Redoubt Volcano lava dome viewed from the southeast. This dome has been slowly growing since April 4, 2009. [Picture Date: May 26, 2009 16:12:26 AKDT – Image Creator: Rick Wessels; Image courtesy of AVO/USGS.

Ongoing Activity:

Latest U.S. Volcano Alerts and Updates for Wednesday, May 27, 2009 7:32 AM HST (Wednesday, May 27, 2009 17:32 UTC)

  • Redoubt Activity – Color Code ORANGE : Alert Level WATCH

  • Kilauea Activity  –  Color Code ORANGE : Alert Level WATCH

  • Veniaminof Activity – Color Code GREEN : Alert Level NORMAL

  • Mauna Loa Activity – Color Code YELLOW : Alert Level ADVISORY

Related Links:

Posted in Kīlauea, Redoubt, volcanic activity, volcanism, VolcanoWatch | Tagged: , , , , | Leave a Comment »

Volcano Watch Weekly [6 May 2009]

Posted by feww on May 7, 2009

Volcanic Activity Report: 29 April – 5 May 2009

Source: Global Volcanism program (GVP) – SI/USGS Weekly Volcanic Activity Report

New activity/unrest:

VoW: Atitlán

Country:  Guatemala
Volcano Type:  Stratovolcano
Volcano Status:  Historical
Last Known Eruption: 1853
Summit Elevation: 3,535 m  (11,598 feet)
Latitude: 14.583°N  (14°34’58″N)
Longitude: 91.186°W  (91°11’11″W)


Volcán Atitlán is one of several prominent conical stratovolcanoes in the Guatemalan highlands. Along with its twin volcano Tolimán to the north, it forms a dramatic backdrop to Lake Atitlán, one of the scenic highlights of the country. The 3535-m-high summit of Atitlán directly overlies the inferred margin of the Pleistocene Atitlán III caldera and is the highest of three large post-caldera stratovolcanoes constructed near the southern caldera rim. The volcano consequently post-dates the eruption of the voluminous, roughly 85,000-year-old rhyolitic Los Chocoyos tephra associated with formation of the Atitlán III caldera. The historically active andesitic Volcán Atitlán is younger than Tolimán, although their earlier activity overlapped. In contrast to Tolimán, Atitlán displays a thick pyroclastic cover. The northern side of the volcano is wooded to near the summit, whereas the upper 1000 m of the southern slopes are unvegetated. Predominantly explosive eruptions have been recorded from Volcán Atitlán since the 15th century. Photo by Bill Rose, 1980(Michigan Technological University). Caption GVP.

Major Volcanoes of Guatemala

REPORT:
Volcanic Hazards at Atitlán Volcano, Guatemala

—J.M. Haapala, R. Escobar Wolf, J.W. Vallance, W.I. Rose, J.P. Griswold, S.P. Schilling, J.W. Ewert, and M. Mota, 2006
Volcanic Hazards at Atitlán Volcano, Guatemala U.S. Geological Survey Open-File Report 2005-1403

Introduction

Atitlán Volcano is in the Guatemalan Highlands, along a west-northwest trending chain of volcanoes parallel to the mid-American trench. The volcano perches on the southern rim of the Atitlán caldera, which contains Lake Atitlán. Since the major caldera-forming eruption 85 thousand years ago (ka), three stratovolcanoes—San Pedro, Tolimán, and Atitlán—have formed in and around the caldera. Atitlán is the youngest and most active of the three volcanoes. Atitlán Volcano is a composite volcano, with a steep-sided, symmetrical cone comprising alternating layers of lava flows, volcanic ash, cinders, blocks, and bombs.

Eruptions of Atitlán began more than 10 ka and, since the arrival of the Spanish in the mid-1400’s, eruptions have occurred in six eruptive clusters (1469, 1505, 1579, 1663, 1717, 1826–1856). Owing to its distance from population centers and the limited written record from 200 to 500 years ago, only an incomplete sample of the volcano’s behavior is documented prior to the 1800’s. The geologic record provides a more complete sample of the volcano’s behavior since the 19th century. Geologic and historical data suggest that the intensity and pattern of activity at Atitlán Volcano is similar to that of Fuego Volcano, 44 km to the east, where active eruptions have been observed throughout the historical period.

Because of Atitlán’s moderately explosive nature and frequency of eruptions, there is a need for local and regional hazard planning and mitigation efforts. Tourism has flourished in the area; economic pressure has pushed agricultural activity higher up the slopes of Atitlán and closer to the source of possible future volcanic activity. This report summarizes the hazards posed by Atitlán Volcano in the event of renewed activity but does not imply that an eruption is imminent. However, the recognition of potential activity will facilitate hazard and emergency preparedness. [Report Menu]

Ongoing Activity:

Latest U.S. Volcano Alerts and Updates for Wednesday, May 6, 2009 at 17:51:20 PDT

Related Links:

Posted in Bagana, Krakatau, Redoubt, Rinjani, Shiveluch | Tagged: , , , , | Leave a Comment »

Weekly Volcano Watch: 2 April 2009

Posted by feww on April 2, 2009

Volcanic Activity Report: 25 March – 31 March 2009

Source: SI / USGS Weekly Volcanic Activity Report

New activity/unrest:

VoW: Bandai

Country: Japan
Region: Honshu Is (Japan)
Volcano Type:  Stratovolcano
Last Known Eruption: 1888
Summit Elevation: 1819 m  (5,968 feet)
Latitude: 37.598°N  (37°35’53″N)
Longitude: 140.076°E  (140°4’32″E)


One of Japan’s most noted volcanoes, Bandai-san rises above the north shore of Lake Inawashiro. The Bandai complex is formed of several overlapping andesitic stratovolcanoes, the largest of which is O-Bandai. Ko-Bandai volcano, which collapsed in 1888, was formed about 50,000 years ago. O-Bandai volcano was constructed within a horseshoe-shaped caldera that formed about 40,000 years when an older volcano collapsed, forming the Okinajima debris avalanche, which traveled to the SW and was accompanied by a plinian explosive eruption. The last magmatic eruption at Bandai took place more than 25,000 years ago, but four major phreatic eruptions have occurred during the past 5,000 years, two of them in historical time, in 806 and 1888.  Seen from the south, Bandai presents a conical profile, but much of the north side of the volcano is missing as a result of the collapse of Ko-Bandai volcano during the 1888 eruption, in which a debris avalanche buried several villages and formed several large lakes. Akahani-yama (extreme right) is another Bandai stratovolcano. The forested ridge at the left foreground is part of an earlier Pleistocene debris-avalanche deposit. Photo by Lee Siebert, 1988 (Smithsonian Institution). Caption: GVP

FEWW Comment: Eastern Gemini Seamount or Mathew Island volcano may erupt by about June 2009.

Ongoing Volcanic Activity:

Elevated Volcanic Activity in the US [Source: USGS]

Wednesday, Apr 1, 2009 at 17:23:17 PDT.

  • Cleveland Alert Level=ADVISORY. Aviation Color Code=YELLOW. As of Apr 1, 2009, 12:22 ADT – No activity reported. (Change to current status occurred on Jan 2, 2009 12:52 ADT from Alert Level UNASSIGNED and Aviation Color Code UNASSIGNED ).
    For more information see http://www.avo.alaska.edu/activity/Cleveland.php
  • Redoubt Alert Level=WARNING. Aviation Color Code=RED. As of Apr 1, 2009, 12:22 ADT – Continuous emissions of steam, volcanic gases, and minor amounts of ash continue at Mt. Redoubt. Altitudes typically below 15,000ft but as high as 25,000ft at times. (Change to current status occurred on Mar 26, 2009 09:43 ADT from Alert Level WATCH and Aviation Color Code ORANGE )
    For more information see http://www.avo.alaska.edu/activity/Redoubt.php
  • Kilauea Alert Level=WATCH. Aviation Color Code=ORANGE. As of Apr 1, 2009, 08:29 HST- Elevated SO2 and some tephra from Halema`uma`u vent; elevated SO2 from Pu`u `O`o vent; lava in tubes to ocean. (Change to current status occurred on Jul 2, 2007 20:09 HST from Alert Level ADVISORY and Aviation Color Code YELLOW ).
    For more information see http://volcanoes.usgs.gov/hvo/activity/kilaueastatus.php
  • Mauna Loa Alert Level=ADVISORY. Aviation Color Code=YELLOW. As of Mar 27, 2009, 09:08 HST – Low level of unrest continues. (Mauna Loa has been at this Alert Level and Color Code since this system was implemented in 2005)
    For more information see http://volcanoes.usgs.gov/hvo/activity/maunaloastatus.php

Volcano Alert Levels & Aviation Color Codes defined at http://volcanoes.usgs.gov/activity/alertsystem.

Posted in Bandai, Batu Tara, Colima, Redoubt, Reventador | Tagged: , , , , | Leave a Comment »

Weekly Volcano Watch: 19 March 2009

Posted by feww on March 19, 2009

Volcanic Activity Report: 11 March – 17 March 2009

Source: SI / USGS Weekly Volcanic Activity Report

New activity/unrest:

VoW: Hunga Tonga-Hunga Ha’apai, Tonga

Tonga Islands 20.57°S, 175.38°W; summit elev. 149 m – submarine volcano

An underwater volcanic eruption near the twin islands of Hunga Tonga and Hunga Ha’apai spewed a large column of  off-white smoke into the air. The plume rose to altitudes of about 8 km [possibly as high as 15km.]

tonga-ap
Hunga Ha’apai eruption [March 17-18, 2009] Aerial photo by Trevor Gregory/AP. Source. Image may be subject to copyright.

Observers flying near the area of Hunga Tonga-Hunga Ha’apai (about 62 km NNW of Nuku’alofa, the capital of Tonga) on 16 or 17 March reported seeing an eruption. Photos showed an eruption plume with a wide base that rose from the sea surface and mixed with meteorological clouds. Based on information from the Tonga airport and analysis of satellite imagery, the Wellington VAAC reported that on 18 March, a plume rose to altitudes of 4.6-7.6 km (15,000-25,000 ft) a.s.l. and drifted NE.

Geologic Summary. The small islands of Hunga Tonga and Hunga Ha’apai cap a large seamount located about 30 km SSE of Falcon Island. The two linear andesitic islands are about 2 km long and represent the western and northern remnants of a the rim of a largely submarine caldera lying east and south of the islands. Hunga Tonga and Hunga Ha’apai reach an elevation of only 149 m and 128 m above sea level, respectively, and display inward-facing sea cliffs with lava and tephra layers dipping gently away from the submarine caldera. A rocky shoal 3.2 km SE of Hunga Ha’apai and 3 km south of Hunga Tonga marks the most prominent historically active vent. Several submarine eruptions have occurred at Hunga Tonga-Hunga Ha’apai since the first historical eruption in 1912. GVP reported.


The small islands of Hunga Tonga and Hunga Ha’apai cap a large seamount located about 30 km SSE of Falcon Island. The two linear andesitic islands are about 2 km long and represent the western and northern remnants of a the rim of a largely submarine caldera lying east and south of the islands. Hunga Tonga and Hunga Ha’apai reach an elevation of only 149 m and 128 m above sea level, respectively, and display inward-facing sea cliffs with lava and tephra layers dipping gently away from the submarine caldera. A rocky shoal 3.2 km SE of Hunga Ha’apai and 3 km south of Hunga Tonga marks the most prominent historically active vent. Submarine eruptions were reported here in 1912 and 1937 and from a fissure 1 km SSE of Hunga Ha’apai in 1988. Aerial photo by Tonga Ministry of Lands, Survey, and Natural Resources, 1991 (published in Taylor and Ewart, 1997). Caption: GVP.


Hunga Tonga-Hunga Ha’apai volcano from space. Image captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite  on March 18, 2008. “In this image, the area around the eruption appears bright blue-green, likely resulting from sediment suspended in the water. The brilliant white patch at the center of the sediment-rich area may result from vapor released by the volcano. Northwest of the eruption site, a serpentine pumice raft floats on the water. The highly porous nature of pumice enables this volcanic rock to form floating rafts. (A larger pumice raft resulted from a similar eruption in the Tonga Islands in August 2006.).” Earth Observatory said.


A March 18 photo of Hunga Tonga-Hunga Ha’apai eruption as seen from the Nuku’alofa waterfront. Photo: AP/Matangi Tonga Online. Source. Image may be subject to copyright.

volcanoes-of-tonga
USGS Map of Major Volcanoes of Tonga with the approximate location of Hunga Tonga-Hunga Ha’apai volcano marked.


Photo dated Wednesday, March 18, 2009. Source: Xinhua/AFP. Image may be subject to copyright.

Video: Underwater volcano erupts off Tonga

Hunga Tonga-Hunga Ha’apai volcano

Flights were disrupted and airlines alerted after the undersea Hunga Tonga-Hunga Ha’apai volcano erupted.  Air New Zealand flights were forced to divert to  avoid  smoke, which reportedly rose to a height of about 15 km, various media reported.

The volcano located about 12km off the southwest coast off the main island of Tongatapu  is thought to have erupted on Monday. Hunga Tonga-Hunga Ha’apai is one of about 40 submarine volcanoes in the area.

It’s thought that the eruption does not pose an immediate threat to the residents because trade winds are blowing the smokes and  gases away from the island.

“It’s a very significant eruption, on quite a large scale.” Said Tonga’s Geological Service Chief, Keleti Mafi.

Rumble III

On March 13, the underwater volcano Rumble III,  located about 300km northeast of Bay of Plenty, New Zealand, was discovered to have undergone a “startling change” losing about 100m of its summit, with the 800m-wide crater completely missing, apparently in a catastrophic explosion.

Metis Shoal

On February 3, FEWW forecast that Metis Shoal, a submarine volcano located midway between the islands of Kao and Late (about 50 km NNE of Kao), was about to erupt, or was currently undergoing a period of unrest.

FEWW moderators believe that both  Metis Shoal, if indeed it has erupted / is erupting, and Hunga Tonga-Hunga Ha’apai volcanoes may have been triggered simultaneously.

FEWW List of Forgotten Volcanoes

Ongoing Volcanic Activity:

Elevated Volcanic Activity and Information Releases

Wednesday, Mar 18, 2009 at 17:47:50 PDT.

The following U.S. volcanoes are known to be above normal background (elevated unrest or eruptions) or have shown activity that warranted an Information Release (for example, an earthquake swarm).

Times are local to the volcano and in 24-hr format.
Volcano Alert Levels & Aviation Color Codes defined at http://volcanoes.usgs.gov/activity/alertsystem.

Volcano Hazards Program Webcams page links to webcams at 19 of the 169 active volcanoes in the U-S.

Related Links:

Posted in Chaiten, Galeras, Metis Shoal, Redoubt, Rumble III | Tagged: , , , , | 2 Comments »

Weekly Volcano Watch: 12 March 2009

Posted by feww on March 12, 2009

Latest U.S. Volcano Alerts and Updates for Thursday, Mar 5, 2009 at 06:40:05 PST

  • 2009-03-11 20:27:47 Okmok Advisory Yellow
  • 2009-03-11 20:27:47 Redoubt Advisory Yellow
  • 2009-03-11 20:27:47 Cleveland Advisory Yellow
  • 2009-03-11 20:07:45 Kilauea Watch Orange
  • 2009-03-03 01:05:40 Mauna Loa Advisory Yellow

Volcano Hazards Program Webcams page links to webcams at 19 of the 169 active volcanoes in the U-S.

Volcanic Activity Report: 4 March – 10 March 2009

Source: SI / USGS Weekly Volcanic Activity Report

New activity/unrest:

VoW: Rainier


Mount Rainier, at 4392 m the highest peak in the Cascade Range, forms a dramatic backdrop to the Puget Sound region. Large Holocene mudflows from collapse of this massive, heavily glaciated andesitic volcano have reached as far as the Puget Sound lowlands. The present summit was constructed within a large crater breached to the north during the a mid-Holocene eruption as a result of the collapse of a once-higher edifice. Several postglacial tephras have been erupted from Mount Rainier; tree-ring dating places the last recognizable tephra deposit during the 19th century. The present-day summit cone was formed during a major mixed-magma explosive eruption about 2200 years ago and is capped by two overlapping craters. Extensive hydrothermal alteration of the upper portion of the volcano has contributed to its structural weakness; an active thermal system has caused periodic melting on flank glaciers and produced an elaborate system of steam caves in the summit icecap. Photo by Lee Siebert, 1983 (Smithsonian Institution). Caption: GVP

  • Country: United States
  • Region: Washington
  • Volcano Type: Stratovolcano
  • Last Known Eruption: 1894
  • Summit Elevation: 4392 m (14,409 feet)
  • Latitude: 46.853°N (46°51’10″N)
  • Longitude: 121.760°W ( 121°45’37″W)

Seattle_Rainier
Mount Rainier photographed from Seattle, WA. Photo dated July 2005. Source. Image may be subject to copyright.

Monthly report (subject to change) from

06/1969 (CSLP 53-69) Increased seismicity since September 1968

“Local activity has been increasing each month for the last three months. We have been averaging about 1-3 ‘Mt. Ranier Events’ per 5-day period with an increase to about five per 5-day period last September 1968. This April, the events increased to approximately five per 5-day period. In May, it increased to about six per 5-day period and as of 15 June the increase is to approximately 12 per 5-day period.”

Information Contact: N. Rasmussen, Seismology Station, University of Washington.

Cascade Range Current Update

CASCADES VOLCANO OBSERVATORY WEEKLY UPDATE
Friday, March 6, 2009 09:05 PST (Friday, March 6, 2009 17:05 UTC)

Source: USGS/Cascades Volcano Observatory, Vancouver, Washington

Cascade Range Volcanoes
Volcano Alert Level: NORMAL
Aviation Color Code: GREEN

Activity Update: All volcanoes in the Cascade Range are at normal levels of background seismicity. These include Mount Baker, Glacier Peak, Mount Rainier, Mount St. Helens, and Mount Adams in Washington State; Mount Hood, Mount Jefferson, Three Sisters, Newberry Volcano, and Crater Lake, in Oregon; and Medicine Lake volcano, Mount Shasta, and Lassen Peak in northern California.
Mount St. Helens has been at Volcano Alert Level NORMAL (Aviation Color Code GREEN) since July 10, 2008.

Recent Observations: Activity at all Cascade volcanoes remained at background levels. A few tiny earthquakes were detected at Mount St. Helens and Mount Shasta.

The U.S. Geological Survey and University of Washington continue to monitor these volcanoes closely and will issue additional updates and changes in alert level as warranted.

Introduction

Mount Rainier at 4393 meters (14,410 feet) the highest peak in the Cascade Range is a dormant volcano whose load of glacier ice exceeds that of any other mountain in the conterminous United States. This tremendous mass of rock and ice, in combination with great topographic relief, poses a variety of geologic hazards, both during inevitable future eruptions and during the intervening periods of repose.

The volcano’s past behavior is the best guide to possible future hazards. The written history of Mount Rainier encompasses the period since about A.D. 1820, during which time one or two small eruptions, several small debris avalanches, and many small lahars (debris flows originating on a volcano) have occurred. This time interval is far too brief to serve as a basis for estimating the future behavior of a volcano that is several hundreds of thousands of years old. Fortunately, prehistoric deposits record the types, magnitudes, and frequencies of past events, and show which areas were affected by them. At Mount Rainier, as at other Cascade volcanoes, deposits produced since the latest ice age (approximately during the past 10,000 years) are well preserved. Studies of these deposits reveal that we should anticipate potential hazards from some phenomena that only occur during eruptions and from others that may occur without eruptive activity. Tephra falls, pyroclastic flows and pyroclastic surges, ballistic projectiles, and lava flows occur only during eruptions. Debris avalanches, lahars, and floods commonly accompany eruptions, but can also occur during dormant periods.

This report (1) explains the various types of hazardous geologic phenomena that could occur at Mount Rainier, (2) shows areas that are most likely to be affected by the different phenomena, (3) estimates the likelihood that the areas will be affected, and (4) recommends actions that can be taken to protect lives and property. It builds upon and revises a similar document prepared by D.R. Crandell in 1973. Our revision was motivated by the availability of new information about Mount Rainier’s geologic history, by advances in the field of volcanology, and by the need to assess hazards in a more quantitative manner than in Crandell’s pioneering report. —R.P. Hoblitt, J.S. Walder, C.L. Driedger, K.M. Scott, P.T. Pringle, and J.W. Vallance, 1998, Volcano Hazards from Mount Rainier, Washington, Revised 1998: U.S. Geological Survey Open-File Report 98-428

REPORT:
Volcano Hazards from Mount Rainier, Washington, Revised 1998

Mount Rainier at 4,393 meters (14,410 feet) the highest peak in the Cascade Range is a dormant volcano whose load of glacier ice exceeds that of any other mountain in the conterminous United States. This tremendous mass of rock and ice, in combination with great topographic relief, poses a variety of geologic hazards, both during inevitable future eruptions and during the intervening periods of repose. … This report (1) explains the various types of hazardous geologic phenomena that could occur at Mount Rainier, (2) shows areas that are most likely to be affected by the different phenomena, (3) estimates the likelihood that the areas will be affected, and (4) recommends actions that can be taken to protect lives and property. It builds upon and revises a similar document prepared by D.R. Crandell in 1973. Our revision was motivated by the availability of new information about Mount Rainier’s geologic history, by advances in the field of volcanology, and by the need to assess hazards in a more quantitative manner than in Crandell’s pioneering report. —Hoblitt, et.al., 1998

Ongoing Activity:

FEWW Forecast: Mount Rainier could erupt in the next 36 months with a probability of 0.65 [and in the next 18 months with a probability of >0.5]

Posted in Cleveland, Koryaksky, Mauna Loa, Okmok, Redoubt | Tagged: , , , , | Leave a Comment »

Weekly Volcano Watch: 5 March 2009 [Take 2]

Posted by feww on March 5, 2009

Latest U.S. Volcano Alerts and Updates for Thursday, Mar 5, 2009 at 06:40:05 PST

Volcano Hazards Program Webcams page links to webcams at 19 of the 169 active volcanoes in the U-S.

Volcanic Activity Report: 25 February-3 March 2009

Source: SI / USGS Weekly Volcanic Activity Report

New activity/unrest:

Volcano of the Week: Jan Mayen


Remote Jan Mayen Island, located in the Norwegian Sea along the Mid-Atlantic Ridge about 650 km NE of Iceland, consists of two volcanic complexes separated by a narrow isthmus. The large Beerenberg basaltic stratovolcano (Nord-Jan) forms the NE end of the 40-km-long island, which is ringed by high cliffs. Beerenberg is a large 2277-m-high glacier-covered stratovolcano with a 1-km-wide summit crater and numerous cinder cones that were erupted along flank fissures. It is composed primarily of basaltic lava flows with minor amounts of tephra. Historical eruptions at Beerenberg date back to the 18th century. The Sor-Jan group of pyroclastic cones and lava domes occupies the SW tip of Jan Mayen. The Holocene Sor-Jan cinder cones, tephra rings, and trachytic lava domes were erupted from short fissures with a NE-SW trend. Photo by Gernot Hecker, 2005 (Wikimedia Commons). Caption: GVP.

  • Volcano: Jan Mayen
  • Country: Norway
  • Subregion: Jan Mayen Island
  • Volcano Type: Stratovolcano
  • Last Known Eruption: 1985
  • Summit Elevation: 2,277 m (7,470 feet)
  • Latitude: 71.08°N (71°5’0″N)
  • Longitude: 8.17°W (8°10’0″W)


Ongoing Activity:

Posted in Chaiten, Jan Mayen, Kīlauea, Redoubt, volcanoes | Tagged: , , , , | Leave a Comment »

Volcano Watch: 10 February 2009

Posted by feww on February 12, 2009

Volcanic Activity Report: 4 February – 10 February 2009

Source: SI / USGS Weekly Volcanic Activity Report

Volcano of the Week: Popocatépetl

A plume of steam and ash rises above Popocatépetl, whose Aztec name means “Smoking Mountain.” This December 1994 aerial view is of the NE side of the massive stratovolcano, which towers more than 3200 m above the Valley of Mexico to the right.

Volcán 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, 400 x 600 m wide 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 precolumbian time.  Photo courtesy of ENAPRED, Mexico City, 1994. Caption: GVP

Volcano Name: Volcán Popocatépetl

Country: México

Volcano Type: Stratovolcanoes

Last Known Eruption: 2008 (in or after)

Summit Elevation: 5426 m (17,802 feet)

Latitude:      19.023°N (19°1’24″N)

Longitude: 98.622°W (98°37’20″W)

“CENAPRED reported that emissions of steam and gas from Popocatépetl were visible during 4-10 February; the plumes occasionally contained slight amounts of ash. On 6 February, an ash plume rose 800 m above the crater at 0839, and was followed by 75 minutes of increased seismicity.” GVP said.

Ongoing Activity:

Posted in Chaiten, Colima, Kīlauea, Redoubt, Volcano Watch | Tagged: , , , , | Leave a Comment »

Volcano Watch: 3 February 2009

Posted by feww on February 5, 2009

Volcanic Activity Report: 28 January-3 February 2009

From: SI / USGS Weekly Volcanic Activity Report

New Activity/Unrest:

Volcano of the Week: Ubinas


Volcán Ubinas, seen here from the west, is Perú’s most active volcano. A small, 1.2-km-wide caldera that cuts the top of Ubinas gives it a truncated appearance. The upper slopes of the stratovolcano steepen to nearly 45 degrees. The steep-walled, 150-m-deep caldera contains an ash cone with a 500-m-wide funnel-shaped vent that is 200-m deep. Holocene lava flows are visible on the volcano’s flanks, but historical activity, documented since the 16th century, has consisted of intermittent minor explosive eruptions. Photo by Norm Banks, 1988 (U.S. Geological Survey). Caption: GVP

Volcano Name: Ubinas

Country: Perú
Volcano Type:  Stratovolcano
Last Known Eruption: 2008 (in or after)
Summit Elevation: 5672 m (18,609 feet)
Latitude: 16.355°S 16°21’18″S
Longitude: 70.903°W 70°54’11″W

Based on a SIGMET notice, the Buenos Aires VAAC reported that on 31 January an ash plume from Ubinas rose to an altitude of 6.7 km (22,000 ft) a.s.l. and drifted SW. Ash was not seen on satellite imagery.

Ongoing Activity:

Posted in Asama, Redoubt, Volcanic Activity Report, volcanism, volcanoes | Tagged: , , , , | Leave a Comment »