Technical hitches… 29 October 2010
Posted by admin in admin.comments closed
I’ve been away in the wilderness and intended to use a wireless connection to keep up with blogging, but the system available turned out not to be up to the job. Additionally, some posts which I thought I had managed to get onto the blog seem not to have appeared. All quite annoying, particularly when there has been so much volcanic action over the past few days. Well, I will sort out the mess and get back to you — apologies for the disruption.
SI/USGS Weekly Volcanic Activity Report, 20-26 October 2010 29 October 2010
Posted by admin in activity reports, Chaitén, Chile, eruptions, Fuego, Guatemala, Hawaii, Indian Ocean, Indonesia, Japan, Kamchatka, Karymsky, Kilauea, Kliuchevskoi, Manam, Merapi, Pacaya, Papua New Guinea, Piton de la Fournaise, Russia, Sakura-jima, Santa María, Shiveluch, Suwanose-jima, United States, Villarrica, Weekly Volcanic Activity Reports.Tags: Global Volcanism Program
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The Weekly Volcanic Activity Report for 20-26 October 2010 is compiled by Sally Kuhn Kennert and published by the Global Volcanism Program. It’s been a volcanically lively week. Some selected highlights:
- Kliuchevskoi: explosive activity
- Merapi: an explosive eruption brings evacuations and fatalities
- Piton de la Fournaise: eruptive activity continues
Click on the map for a larger version (1280 x 898 pixels).
The Smithsonian Institution/United States Geological Survey Weekly Volcanic Activity Report for 20-26 October 2010 is now available on the Global Volcanism Program website. The following is a summary and not a substitute for the full report.
- The current report: Weekly Volcanic Activity Report.
- Previous reports: Weekly Reports Archive.
- The SI/USGS map of volcanoes discussed this week.
New activity/unrest: Kliuchevskoi (Russia), Merapi (Indonesia), Piton de la Fournaise (Réunion Island).
Ongoing activity: Chaitén (Chile), Fuego (Guatemala), Karymsky (Russia), Kilauea (Hawaii, USA), Manam (Papua New Guinea), Pacaya (Guatemala), Sakura-jima (Japan), Santa María (Guatemala), Shiveluch (Russia), Suwanose-jima (Japan), Villarrica (Chile).
SI/USGS Weekly Volcanic Activity Report, 13-19 October 2010 23 October 2010
Posted by admin in activity reports, Caribbean, Chile, Ecuador, eruptions, Gorely, Hawaii, Indian Ocean, Japan, Kamchatka, Karymsky, Kilauea, Kliuchevskoi, Piton de la Fournaise, Planchón-Peteroa, Russia, Sakura-jima, Sangay, Shiveluch, Soufrière Hills, Suwanose-jima, United States, Villarrica, Weekly Volcanic Activity Reports.Tags: Global Volcanism Program
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The Weekly Volcanic Activity Report for 13-19 October 2010 is compiled by Sally Kuhn Kennert and published by the Global Volcanism Program. Some selected highlights:
- Piton de la Fournaise: eruption began on 14 October
- Gorely: seismic restlessness at this Kamchatka volcano
- Shiveluch: elevated seismic activity, gas, steam and ash plumes
Click on the map for a larger version (1280 x 898 pixels).
The Smithsonian Institution/United States Geological Survey Weekly Volcanic Activity Report for 13-19 October 2010 is now available on the Global Volcanism Program website. The following is a summary and not a substitute for the full report.
- The current report: Weekly Volcanic Activity Report.
- Previous reports: Weekly Reports Archive.
- The SI/USGS map of volcanoes discussed this week.
New activity/unrest: Piton de la Fournaise (Réunion Island).
Ongoing activity: Gorely (Russia), Karymsky (Russia), Kilauea (Hawaii, USA), Kliuchevskoi (Russia), Planchón-Peteroa (Chile), Sakura-jima (Japan), Sangay (Ecuador), Shiveluch (Russia), Soufrière Hills (Montserrat), Suwanose-jima (Japan), Villarrica (Chile).
Signs of increasing activity at Galeras 20 October 2010
Posted by admin in activity reports, Colombia, Galeras.comments closed
The Observatorio Vulcanológico y Sismológico de Pasto reports (bulletin of 19 October) that Galeras volcano is continuing to show increasing signs of activity after a relatively quiet few weeks. Galeras has remained at the third-highest alert level of Yellow since 7 September, when the alert level was lowered from Orange following the eruption of 25 August.
Seismic activity at Galeras continues to fluctuate, with an increase in seismic signals associated with fluid movements within the volcano since 15 October. This increased seismicity is also associated with increased gas emissions, and in the ash content of those emissions, and there has been an increase in deformation at the summit of the volcano and thermal anomalies have been detected in the crater area. All these parameters, INGEOMINAS concludes, indicate ‘the presence of magmatic material at shallow levels which continues to intrude towards the surface’.
In anticipation of a potential eruption Colombia’s Sistema Nacional para la Prevención y Atención de Desastres has advised the people living near Galeras to ‘be attentive to the recommendations of the authorities’ (they tend not to be, as as rule).
References to volcano alert levels on this blog are not authoritative and are not necessarily up to date. You should always check with official sources for the latest alert levels.
For all our Galeras coverage: Galeras « The Volcanism Blog.
News
El volcán Galeras presenta signos de reactivación – El Tiempo, 20 October 2010
Alerta por incremento de la actividad del vólcan Galeras – El País, 20 October 2010
Alerta por incremento en actividad volcánica del Galeras – Terra Colombia, 20 October 2010
Volcán Galeras incrementó actividad volcánica – Radio Santa Fe, 20 October 2010
Information
Global Volcanism Program – Galeras – summary information for Galeras (1501-08=)
Portal Corporativo de INGEOMINAS – Instituto Colombiano de Geología y Minería
Observatorio Vulcanológico y Sismológico de Pasto – Pasto volcanological observatory main page
SI/USGS Weekly Volcanic Activity Report, 6-12 October 2010 14 October 2010
Posted by admin in activity reports, Arenal, Argentina, Batu Tara, Caribbean, Chile, Costa Rica, Dukono, Ecuador, eruptions, Hawaii, Indonesia, Japan, Kamchatka, Karymsky, Kilauea, Kliuchevskoi, Piton de la Fournaise, Planchón-Peteroa, Poás, Reventador, Russia, Sakura-jima, Sangay, Shiveluch, Soufrière Hills, United States, Weekly Volcanic Activity Reports.Tags: Global Volcanism Program
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The Weekly Volcanic Activity Report for 6-12 October 2010 is compiled by Sally Kuhn Kennert and published by the Global Volcanism Program. Some selected highlights:
- Piton de la Fournaise: continuing high level of activity, with elevated seismicity and summit inflation
- Planchón-Peteroa: plumes rising to altitudes between 3 and 6 km a.s.l.
- Poás: phreatic eruptions throw material tens of metres above the surface of the crater lake
Click on the map for a larger version (1280 x 898 pixels).
The Smithsonian Institution/United States Geological Survey Weekly Volcanic Activity Report for 29 September – 5 October 2010 is now available on the Global Volcanism Program website. The following is a summary and not a substitute for the full report.
- The current report: Weekly Volcanic Activity Report.
- Previous reports: Weekly Reports Archive.
- The SI/USGS map of volcanoes discussed this week.
New activity/unrest: Piton de la Fournaise (Réunion Island), Planchón-Peteroa (Chile), Reventador (Ecuador).
Ongoing activity: Arenal (Costa Rica), Batu Tara (Indonesia), Dukono (Indonesia), Karymsky (Russia), Kilauea (Hawaii, USA), Kliuchevskoi (Russia), Poás (Costa Rica), Sakura-jima (Japan), Sangay (Ecuador), Shiveluch (Russia), Soufrière Hills (Montserrat).
Chile: the latest from Planchón (and Chaitén) 8 October 2010
Posted by admin in activity reports, Argentina, Chaitén, Chile, eruptions, Planchón-Peteroa.comments closed
Chilean state geological service SERNAGEOMIN has issued a new bulletin (4 October 2010) giving the latest information about the ongoing activity at Planchón-Peteroa and Chaitén volcanoes.
The report on Planchón-Peteroa, covering the period 16-30 September, says that data from monitoring of the volcano indicates that ‘the current activity is characterized by the active presence of a body of magma, interacting with the upper hydrothermal system of the volcano, which continues in a minor eruptive process’. A high level of seismic activity has been recorded, associated with fluid movements in the interior of the volcano. including a continuous tremor signal. An overflight on 30 September revealed that the volcano is continuing to produced ‘pyroclastic eruptive activity of a low intensity’, but that there has been a ‘slight increase in the vigour of the emissions compared with that seen over the last three weeks’. Other observations from the overflight:
The eruptive activity has remained constant in the south-western crater, with a relatively dense column of ash, gases and diffuse emanations of water vapour. The emission of ash and gases was maintained from the lower north-eastern edge of the crater, but it was more continuous and vigorous than was observed during the flights of 7 and 9 September. From the air, a column a little more dense than on those occasions could be observed.
The ash column rising from the crater was inclined towards the east to a height of approximately 400 metres above the level of emission. From this point the column was dispersed and diluted over a wide area of Argentine territory. During the overflight, the greater part of the ash plume in suspension was distributed towards the east and, from there, a part towards the north-east, for tens of kilometres, at heights of up to 6000 metres a.s.l. A more dilute trace of the plume extended to the south and south-east at maximum altitudes of 3000 metres a.s.l. between Argentine valleys.
The report concludes that the volcano’s current behaviour suggests that ‘the magma body and the hydrothermal system are remaining in a certain equilibrium’. The alert level remains at Yellow level 4.
A detailed version of the Planchón bulletin in PDF can be found by going to the ‘informes’ page on the horrible OVDAS website and clicking on Región del Maule (VII) Volcán Planchón-Peteroa in the list under ‘Informes, Reportes y Otros Informes’ for the list of recent reports, or you can open the PDF directly by clicking here.
As for Chaitén, things remain active but quiet: a slight increase in seismic activity was registered during 20-28 September compared to levels earlier in the month, but ‘the energy released by the volcanic system remains at relatively low levels, comparable to earlier months’. SERNAGEOMIN is maintaining an alert level of Yellow level 3.
Watching Planchón: the main page of the Proyecto Observación Volcán Villarrica (POVI) website currently features information on the Planchón activity, and SERNAGEOMIN-OVDAS has a webcam at Romeral which provides a very good view of Planchón-Peteroa, weather permitting.
References to volcano alert levels on this blog are not authoritative and are not necessarily up to date. You should always check with official sources for the latest alert levels.
[Thanks to Guillermo for letting me know about the new SERNAGEOMIN bulletin.]
Information
Global Volcanism Program: Planchón-Peteroa – summary information for Planchón-Peteroa (1507-04=)
Global Volcanism Program: Chaitén – summary information for Chaitén (1508-041=)
Servicio Nacional de Geología y Minería – Chilean state geological service SERNAGEOMIN
Observatorio Volcanológico de los Andes del Sur – the ghastly website for OVDAS
Phytoplankton flourishes as Kasatochi’s ash fertilizes the ocean 8 October 2010
Posted by admin in Alaska, current research, Kasatochi.Tags: oceanography, phytoplankton, volcanic ash
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The eruption of Alaska’s Kasatochi volcano in August 2008 has led to a surge in the population of phytoplankton in the North Pacific, says a paper in Geophysical Research Letters authored by a horde of scientists from institutions in Canada, the USA and the UK, led by oceanographer Roberta C. Hamme of the University of Victoria, British Columbia. An unusual storm system meant that the ash deposited by the volcano was transported across a very wide area of the north-eastern Pacific, and the iron content encouraged the growth of phytoplankton (for which iron is a key nutrient), producing one of the largest plankton blooms ever recorded in this region. Scientists have recently suggested that volcanic ash fertilization of the ocean in this way can occur, but, as Professor Hamme notes in the very useful summary of the Kasatochi paper she has made available as a PDF on her website (wish more scientists would do that), this is the first time conclusive evidence has been obtained to support the hypothesis.
Because phytoplankton (which are the basis of oceanic and freshwater food chains) consume carbon dioxide and release oxygen, seeding the oceans with iron to encourage their growth has sometimes been suggested as a means of diminishing atmospheric CO2. However, the evidence of the naturally-occurring Kasatochi seeding episode is that the process is not very efficient and that it would take a lot of iron to make even a small difference.
- Roberta C. Hamme et al. ‘Volcanic ash fuels anomalous plankton bloom in subarctic northeast Pacific’, Geophysical Research Letters, 37 (2010), doi:10.1029/2010GL044629. [abstract]
News
How volcanoes feed plankton – ScienceNow, 5 October 2010
Effects of volcanic eruption dash promising global warming theory – Globe and Mail, 5 October 2010
Volcano ‘seeded’ ocean bloom – UPI.com, 6 October 2010
Volcanic arcs: it’s all in the melt 8 October 2010
Posted by admin in current research, geoscience, volcanology.comments closed
We all know that volcanic arcs are related to subduction zones: the areas of the Earth’s surface where an oceanic lithospheric plate comes up against another plate and moves beneath it, ultimately being re-absorbed into the mantle in a vast geological recycling scheme. The oceanic rock is full of water, which begins to be released as it reaches greater depths and becomes subject to increased heat and pressure, entering the overlying mantle wedge that lies between it and the continental lithosphere and lowering its melting point, producing melt that ascends to feed volcanoes above the subduction zone. In offshore island arcs and continental volcanic arcs the line of volcanoes is always offset some way from the point at which the subducted plate makes its dive, which is marked by an oceanic trench.
Various explanations have been put forward for why the volcanoes appear where they do, usually connected to theories as to the locations of the points of highest temperature in the zone where the upper surface of the subducted slab and the mantle wedge are in contact with each other. No-one has really got to the bottom of it, however (so to speak). But two researchers from the University of Oxford Department of Earth Sciences, Philip C. England and Richard F. Katz, have been working on this problem in a new way, by applying a mathematical model of heat transport in this zone to establish where the areas of highest temperature, and thus of melt production, occur. Their conclusion is that the locations of subduction zone volcanoes can only be explained if they emerge above regions in which mantle is melting in the absence of water. Hydrous melting — melting associated with the presence of water — pervades the mantle wedge, but the conventional models of arc formation suggest that there is a particular point at which the degree of hydrous melting increases rapidly because of conditions of temperature and/or pressure, and that the arc front forms above this point. Yet these processes of hydrous melting occur not in a restricted area of the wedge but across a broad region of the mantle core, raising the issue of how the melt then becomes concentrated to feed a relatively narrow volcanic arc. England and Katz avoid that difficulty by invoking the crystallization of rising magma as it reaches the thermal boundary layer at the top of the wedge. This deflects the magma back towards the trench and into the ‘nose’ of the mantle wedge, whence it makes its way upwards by thermal erosion, opening pathways for hydrous melt which drives the volcanism of the arc.
The paper, ‘Melting above the anhydrous solidus controls the location of volcanic arcs’ by can be found in the 7 October 2010 issue of Nature. It’s subscribers only of course: the link below will give you the abstract, to read further you need to log in or pay up.
- Philip C. England & Richard F. Katz, ‘Melting above the anhydrous solidus controls the location of volcanic arcs’, Nature, 700–703 (07 October 2010), doi:10.1038/nature09417. [abstract]
A new Icelandic volcanoes and earthquakes blog 8 October 2010
Posted by admin in blogs, geoblogosphere, Iceland, volcano monitoring.comments closed
Iceland is volcanoes, and anyone who has been following volcanic events in Iceland recently — and there have been plenty, of course — will be familiar with the work of Jón Frímann, who (to quote Erik Klemetti) ‘has information on every noise the volcanoes of Iceland make’. He’s been sharing that information via the comments threads at Eruptions for some time, and has now set up his own blog, the Iceland Volcano and Earthquake blog. It’s dense with detail about what the volcanoes of Iceland are up to: earthquakes, tremor, inflation/deflation, emissions, the lot. Essential reading if you want to know what is happening in the land of fire and ice.
SI/USGS Weekly Volcanic Activity Report, 29 September – 5 October 2010 7 October 2010
Posted by admin in activity reports, Bagana, Batu Tara, Caribbean, Chile, Colombia, Dukono, Ecuador, eruptions, Fuego, Guatemala, Hawaii, Indonesia, Japan, Kamchatka, Karymsky, Kilauea, Kliuchevskoi, Mexico, Nevado del Huila, Nevado del Ruiz, Pacaya, Papua New Guinea, Piton de la Fournaise, Planchón-Peteroa, Popocatépetl, Reventador, Russia, Sakura-jima, Sarychev Peak, Shiveluch, Soufrière Hills, Suwanose-jima, United States, Weekly Volcanic Activity Reports.comments closed
The Weekly Volcanic Activity Report for 29 September to 5 October 2010 is compiled by Sally Kuhn Kennert and published by the Global Volcanism Program. Some selected highlights:
- Nevado del Huila: ash emissions reported at an altitude of 7.6 km
- Nevado del Ruiz: increased seismicity, deformation and geochemical changes causing concern
- Kilauea: a new breakout lava flow causes fires
- Sarychev Peak: a diffuse ash plume reported
Click on the map for a larger version (1280 x 898 pixels).
The Smithsonian Institution/United States Geological Survey Weekly Volcanic Activity Report for 29 September – 5 October 2010 is now available on the Global Volcanism Program website. The following is a summary and not a substitute for the full report.
- The current report: Weekly Volcanic Activity Report.
- Previous reports: Weekly Reports Archive.
- The SI/USGS map of volcanoes discussed this week.
New activity/unrest: Nevado del Huila (Colombia), Nevado del Ruiz (Colombia), Piton de la Fournaise (Réunion Island), Planchón-Peteroa (Chile), Reventador (Ecuador).
Ongoing activity: Bagana (Papua New Guinea), Batu Tara (Indonesia), Dukono (Indonesia), Fuego (Guatemala), Karymsky (Russia), Kilauea (Hawaii, USA), Kliuchevskoi (Russia), Pacaya (Guatemala), Popocatépetl (Mexico), Sakura-jima (Japan), Sarychev Peak (Russia), Shiveluch (Russia), Soufrière Hills (Montserrat), Suwanose-jima (Japan).
