Category Archives: South America

Today in Geological History; Feb 19th – Huaynaputina 1600

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Today 416 years ago South America experienced its most explosive eruption in historical times. The unassuming Huaynaputina volcano sits in southern Peru just 26 km of Ubinas, the countries most active volcano. Unlike its 5672 m neighbour, Huaynaputina has no distinct topographic elevation and lays inside a 2.5 km crater leading many to believe it was just a mountain caused by other forces. Laying in the Andean Volcanic Belt where the Nazca Plate subducts under the western edge of the South American Plate it is situated on the rim of the Rio Tambo canyon further camouflaging it to the untrained eye.

The sleeping giants last eruption was in February 1600. Reaching an impressive VEI 6, it was the biggest eruption of the past 2000 years.

Details of the eruption were captured beautifully by Fray Antonio Vazquez de Espinosa a Spanish monk travelling through Central and South America at the time. Days before the eruption booming noises were heard from the vicinity and steam was seen seeping from the volcano. Locals began to panic, preparing young girls for sacrifice to appease Supay the god of death who people believed was angry at them and causing the mountains behaviour. February 15th marked a strong increase in activity with tremors becoming stronger and more frequent, many began to leave the area fearing something bigger was coming.

At roughly 5 P.M. on February 19th, Huaynaputina erupted violently catapulting ash high in to the stratosphere. Pyroclastic flows sped down all sides of the volcano, to the south mixing with the waters of the Rio Tambo river causing devastating lahars.  Within just 24 hours, Arequipa was covered with 25 centimetres (10 in) of ash. Ashfall was reported 250–500 kilometres (160–310 mi) away, throughout southern Peru and in what is now northern Chile and western Bolivia. It is thought that more than 1500 people were killed by the eruption its self although with little record of populations at the time the figure varies between sources. 10 villages were completely buried by ash and regional agricultural economies took 150 years to recover fully.

It was not just South America which was effected by the eruption. Ice cores recorded a spike in acidity at the time indicating a phenomenal amount of sulphur dioxide was released. Effects on the climate right around the Northern Hemisphere (Southern Hemispheric records are less complete), leading to 1601 being the coldest year in six centuries, leading to one of the worst famines ever recorded in Russia. In Estonia, Switzerland and Latvia, there were bitterly cold winters in 1600–1602 leading the deaths of hundreds; in 1601 in France, the wine harvest came late and in Germany production of wine collapsed completely. In Japan, Lake Suwa had one of its earliest freezings in 500 years and even China recorded peach trees blooming late.

An eruption of this scale in the populated Peru would be devastating so close watch is kept on Huaynaputina and its more active neighbours.

 

Figure 1; https://commons.wikimedia.org/wiki/File:Huaynaputina.jpg

Figure 2; https://volcanohotspot.wordpress.com/2015/04/12/volcanoes-of-peru-3-huaynaputina-catastrophe-in-1600/

 

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The Decade Volcanoes

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As I reblogged my last post, a revision of the Decade volcano list by the authors of VolcanoCafe, I thought before I bring you the new list I should really explain what the original one actually was!

As mentioned in one of my earliest articles, the list was complied in 1990 by the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) a nongovernmental society. The aim was to select the worlds most hazardous volcanoes and put measures in place to keep a closer eye on them and raise awareness across the globe on the threats they pose, for a decade (1991-2000 The UN’s International Decade of Natural Disaster Reduction). Based on varied criteria from historic eruptions to local populations, the following made the cut;

Figure 1. USGS map of the decade volcanoes.

15 Years on the list is still going all though monitoring in some areas may have slackened slightly. It has seen some success such as the diversion of a lava flow on Etna back in 1992 and has helped form a better understanding of phreatic eruptions on Taal. It has sadly also come at great loss on several occasions as well. Despite increased monitoring of Unzen in 1991 pyroclastic flows killed 43 including volcanologists Katia and Maurice Krafft and Harry Glicken.  And even closer to the project, in 1993 the Decade Volcano conference took place in Pasto, Columbia an expedition from the conference to the Galeras crater occurred on February 14th when the volcano suddenly erupted. 3 tourists and 6 volcanologists including Professor Geoff Brown, Head of Department of Earth Science at the Open University, all lost their lives.

Many volcanologist are sceptics and/or critics of the program, hence the call for a revamp. Personally I feel any thing which promotes volcanic awareness is great all though there are some which need much more than others. Volcanoes are ever evolving and unlike most geological features can change in minutes rather than millennia and therefore prehaps a decade is too long for reviews of such a program. I know which have made my list, it will be interesting to see what makes the cut for the guys at VolcanoCafe!

Figure 1. http://listas.20minutos.es/lista/volcanes-de-la-decada-decade-volcanoes-301649/

Eruption Update

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I may have bee quiet on eruption updates lately but that is far from meaning our restless Earth has been quiet. Here is some of the recent updates.

Kilauea 

As Kilauea has been in a constant state of eruption since 1983, some don’t consider changes in activity as news. However as the June 27th lava showed us this relatively calm giant still poses a threat to people.

USGS reports suggest that the summit is still inflating; 7.5 microradians were recorded in the past week alone. Over the weekend we saw rapid filling of the Halema’uma’u crater from a depth of 90 ft from the crater rim to within 10 ft by Sunday lunch time. Yesterday (April 29th) the webcam observed small explosions and spattering with rock falls as the crater began to overflow.

Seismicity remains at an increased level towards the summit and East rift zone where wide spread breakouts from the eruption site are active as close as 8 km of Pu’u ‘O’o. There has be net inflation of Pu’u ‘O’o over the past week but not as significant as at the summit. As the June 27th Lava flows nears its 1 year anniversary incandesance indicates that surface flows remain active northeast of Pu’u ‘O’o.

Calbuco

Although the more explosive phase of the eruption seems to have died down, there are still high ash emissions and flight disruption is still an issue across both Chile and Argintina with ash plumes trailing to the north and south east at just over 1.5 km high. The 20 km exclusion zone is still inplace however it is belived that some people have returned to their homes within the area with maximum displaced 6,514 at the begining of this week. Seismicity has since declinded but it is still under observation.

Sinabung

Collapse of the lava dome on April 28th caused a pyroclastic flow to surge down the flanks. Luckily exclusion zones are still in place from activity over the past few months. The Darwin VAAC  said an ash columb exceeds 14,000 ft although satalitte confirmation has not been possible due to cloud coverage.

Aira

JMA reported that 29 explosions from Showa Crater at Aira Caldera’s Sakurajima volcano ejected tephra as far as 1,300 m during 20-24 April. Nine of the explosions generated ash plumes that rose 3 km above the crater rim; one explosion, on 24 April, produced an ash plume that rose 4 km. Incandescence from the crater was visible on one night. The Alert Level remained at 3 (on a scale of 1-5). Based on JMA notices, the Tokyo VAAC reported that explosions during 22-28 April generated plumes which rose to altitudes of 1.5-4.9 km and drifted S, SE, E, NE, and N.

Tungurahua

Moderate-to-high seismic activity at Tungurahua during 22-28 April, characterized by long-period events, tremor, and explosions. On 28 April an emission with a minor ash content rose 3 km and drifted W. Roaring was noted and lahars descended the La Pampa (NW) and Rea drainages.

Popocatepetl

During 22-28 April the seismic network at Popocatépetl recorded 25-91 daily emissions mostly consisting of water vapor and gas. Cloud cover sometimes prevented observations of the crater, although gas plumes and nighttime crater incandescence were noted daily. On 22 April an explosion at 01.21 produced diffuse gas and water vapor emissions. Explosions at 16.43 and 17.58 local time generated ash plumes. The Alert Level remained at Yellow, Phase Two.

Krakatoa

PVMBG reported that during 1 March-21 April diffuse white plumes rose 25-50 m above Anak Krakatau, although foggy weather often prevented observations. Seismicity continued to be dominated by shallow and deep volcanic earthquakes, as well as signals indicating emissions. The Alert Level remained at .

Sheveluch

During 17-24 April the lava dome extrusion onto Sheveluch’s N flank was accompanied by incandescence, hot block avalanches, and fumerolic activity. A thermal anomaly was detected during 16-18 and 23 April; cloud cover obscured views on the other days. The aviation code remained at Orange.

Figure 1; http://fineartamerica.com/featured/halemaumau-by-moonlight-grant-kaye.html

Figure 2; http://news.yahoo.com/image-asia-pyroclastic-flows-erupt-mount-sinabung-121702289.html

Calbuco

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I awoke this morning to my phone buzzing with notifications. Not just the usual earthquake alerts and job search emails, but while I slept Calbuco in Chile had begun a tremendous eruption. Many of my friends and family had sent me tweets and links to eruption update; have to say it touched me that so many know my passion for these things.

Figure 1. High out put of SiO2 quickly coloured the skyline with stunning pink and red hues.

I have not yet found an estimate for the ouput of either eruption but it is very evidant that high levels of SiO2 were released as the skyline quickly appeared purples and pinks giving us some spectacular imagery of the eruption as seen in figure 1 above. 
Calbuco is sat near the tourist area of Puerto Montt in Southern Chilie. It is apart of the second largest volcanic chain in the world (Indonesia being the largest), but despite the high levels of activity in the region this particular volcano has been quiet for the past 42 years. This changing rapidly yesterday afternoon. Very little warning was given in the run up to the initial blast with a volcanic swarm occurring just before 6 pm local time and then the eruption began at roughly 6.15. A second spate of activity began around 1.05 am this time with lava being clearly visible through the pyroclastic material. The Bueno Aries VAAC puts the eruption column at 10 km (33,000 ft) although there is speculation from other sources that it is nearly double that. Chile has actually been relatively quiet volcanically this with only Villarrica giving us a show in March. This outburst is believed to be much larger and may be more prolonged.

  
Calbuco, albeit quiet recently, actually caused one of Chile’s worst eruptions back in 1893-94.  Although the seen seems to have calmed since the second blast it is strongly believed that this eruptive phase is not over and further eruptions may occur in the next few days or weeks. It is also thought a more careful watch will now also be made on Puyehue which often erupts at the same time of soon after Calbuco. Andean volcanoes are typically very explosive due to the andesitic lavas they produce. 

 

Figure 1; http://time.com/3832353/calbuco-volcano-erupts-chile/?xid=tcoshare

Comparing Past and Present

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Over the last 12 months we have seen some amazing eruptions, felt the Earth shake on numerous occasions, and remembered some historic events. But was the active of 2014, both volcanically and seismically, more than any other year? I have read several spam articles recently, scare mongering that fracking has trebled earthquake numbers, God’s wrath has been shown by volcanic eruptions and even one drunken woman tried to tell me that Japans tectonic misfortune is due to the Pearl Harbor attack!

Lava field at Holuhraun, Iceland September 2nd 2014.

1. Lava field at Holuhraun, Iceland September 2nd 2014.

Now straight away I can assure you that karma or religious intervention has nothing to do with the science behind the mechanics of the planet beneath our feet. Fracking is up for debate and its effects on seismicity although even were proven the effects are still negligible. So has 2014 really been worse than previous?

Seismically

I found quiet a nice table to demonstrate this one courtesy of Wikipedia.

Number of Earthquakes Worldwide for 2004–2014

  Magnitude Ranging

Between

 2004  2005  2006  2007  2008  2009  2010  2011  2012  2013  2014
8.0–9.9 2 1 2 4 0 1 1 1 2 2 1
7.0–7.9 14 10 9 14 12 16 21 19 15 17 11
6.0–6.9 141 140 142 178 168 144 151 204 129 125 144
5.0–5.9 1515 1693 1712 2074 1768 1896 1963 2271 1412 1402 1577
4.0–4.9 10888 13918 12838 12080 12292 6805 10164 13303 10990 9795 14941
Total 12560 15762 14703 14350 14240 8862 12300 15798 12548 11341 16674

2014 actually had the lowest number of strong, magnitude 7 and above earthquakes then in the past 5 years. On the flip side of this we had many more lower magnitude  4-5.9 giving us the highest total of quakes in the past 10 years by about 900 earthquakes. 2009 actually is the strangest year on this list with a good 4000 less earth quakes of any magnitude than any other year. 2007 also stands out with an exceptional number of stronger earthquakes. It could be theorized that the greater release of stress and strain with in the crust during 2007 gave us a quiet period the following years. All though this is a very short time scale it does show that yearly variation is great.

625 people were killed in earthquakes last year with most of these during August 3rd’s Ludian County earthquake in China. 6 lost their lives in the strongest quake of the year in Iquique, Chile which was mg 8.2. Nicaragua and Papua New Guinea also had one fatality each. This is actually quiet low value with over 1500 loosing their lives the previous year or as high as nearly 300,000 in 2004!

Uplift caused by Mg 8.2 Chile Earthquake.

2. Uplift caused by Mg 8.2 Chile Earthquake.

Volcanically

2014 was a pretty explosive year with Sinabung kicking us off with a bang January 3rd as it has done this year. In February the same volcano killed 11 as people began to cross the exclusion zones to take a closer look after the pyrotechnics the month previous.

Bárðarbunga stole the show over the summer. The sleeping giant started a ‘will it, won’t it’ game months before any real activity started in August. Many feared we would see an Eyjafjallajökull 2010 style explosion that would disrupt air traffic at the height of the summer period. Earthqaukes then began to indicate magma was on the move through a dyke heading north-west from the main vent. New fears struck as experts wondered would we see devastation similar to Laki 1783. August 29th saw the start of a large fissure breaking the surface, although it has not reached the status of Laki, the eruption is still continuing today

3. San Miguel

3. San Miguel

 

The next lot a fatalities happened when Mount Ontake surprised all with a phreatic blast on September 27th. 57 lost their lives as hikers and tourists where making their way to a shrine on the mountains flank.

Fogo was the volcano to cause chaos in the final month of the year forcing thousands from their homes. Media coverage of this even has been so light on this event, I am unable to find precise news to if the eruption is ongoing. At December 23rd lava was still pouring from the Pico vent and destroying all in its path.

Obviously these are but a few of the hundreds of volcanoes rumbling through 2014. Others include; Colinma, Etna, Aire, Asonsan, Manam, Merapi, Popcatepetl, Shishaldin, Cleveland, Sabancaya, Zhupanovsky, Sheveluch, Santa Maria, Mayon, Dukono, Turrialba, Poas, Fuego, Ubinas, Tungurahua, Reventador, Pacaya, Karymsky, Kelut, Stromboli, San Miguel, Pavlof, Chirpoi and even all that does not cover them all!

But is this more than usual?

In terms of lava output, last year is definitely high up there as we saw several huge effusive eruptions(with Bárðarbunga probably producing more material than most others put together!). However in the grand scheme of things there were few other major events.

68 people lost their lives which is relatively high thinking that on average maybe one or two die yearly unless there are major volcanic events, but then when thinking like that 68 is actually extremely low.

If we were to pull out any year for increased volcanic activity, for me it would have to be the events of 1902. In a list compiled by Wikipedia* of the most deadly eruptions, although none of the top 5 occurred in 1902, 4 in the list of 40 that occurred did, meaning 10% of the most fatal eruptions occurred in the one year. Well over 40,000 were killed over these four eruptions.

4. Somber scene after Mount Pelee eruption May 8th 1902.

4. Somber scene after Mount Pelee eruption May 8th 1902.

Just over 30,000 of these deaths were caused by Mount Pelee, Martinque on May 8th. Just hours before, La Soufriere a few islands away on Saint Vincent killed 1680.

There will always be years there is more geologically activity than others. The Earth is like a living breathing organism; it is ever-changing and adapting, this is part of the reason predicting events can be tricky.  People always look to blame or find meaning behind tragedy, it’s a coping mechanism, but rarely leads to scientific truth.

Figure 1. http://mashable.com/2014/09/11/iceland-bardabunga-volcano-eruption-photos/

Table 1. http://en.wikipedia.org/wiki/Earthquakes_in_2014

Figure 2. http://www.sneakymag.com/life/the-sneakington-post-3/

Figure 3.  http://www.telegraph.co.uk/news/10541931/El-Salvador-begins-evacuations-due-to-volcano-eruption.html

* http://en.wikipedia.org/wiki/List_of_volcanic_eruptions_by_death_toll

Figure 4. http://www.explorevolcanoes.com/Martinique-caribbean-volcano.html

Eruption Update; Bardabunga, Mayon, Kilaeua and more

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Bárðarbunga

Yes the might fissure is still going strong in the Holuhran lava field. It is now being coined as one of the largest effusive eruptions Iceland has seen in the past 150 years. In terms of lava production it is only second to Hekla’s 1947-48 13month long eruption, however this title could be taken in as little as two weeks if output continues at the rate it is now. Seismicity has decreased since August but we are still seeing low levels along the dyke and stronger quakes under Bárðarbunga particularly around the caldera rim. The Scientific Advisory Board of the Icelandic Civil Protection is still suggesting the following three scenarios are considered most likely: 

  • The eruption on Holuhraun declines gradually and subsidence of the Bardarbunga caldera stops. 

  • Large-scale subsidence of the caldera occurs, prolonging or strengthening the eruption on Holuhraun. In this situation, it is likely that the eruptive fissure would lengthen southwards under Dyngjujokull, resulting in a jokulhlaup and an ash-producing eruption. It is also possible that eruptive fissures could develop in another location under the glacier.

  • Large-scale subsidence of the caldera occurs, causing an eruption at the edge of the caldera. Such an eruption would melt large quantities of ice, leading to a major jokulhlaup, accompanied by ash fall.

SiO2 emissions are still one of the most pressing concerns for the Icelandic people. Pollution warnings are constant, and the met office has consistently tracked the SiO2 cloud which changes course with change in weather.

1. Map of current SiO2 cloud coming from the fissure site.

1. Map of current SiO2 cloud coming from the fissure site.

 

Mayon

All evidence still indicates to a potentially major eruption could occur in the next few weeks. Phivolcs has said that there has been at least five rock fall events in the past 24 hours and one volcanic tremor. Ground deformation continues with at least 3 mm of inflation recorded in the past 10 days. At times of good visibility white steam plumes are seen drifting northwest from the summit and monitors are recording SiO2 emissions at an average of  308 tonnes a day. The 6-km radius Permanent Danger Zone (PDZ) around the volcano is still in place as well as the 7-km Extended Danger Zone (EDZ) on the southeastern flank due to the danger of rock falls, landslides and sudden explosions or dome collapse that may generate hazardous volcanic flows.

For day to day bulletins visit Phivolcs; http://www.phivolcs.dost.gov.ph/index.php?option=com_content&view=category&id=70&Itemid=500008

 

Kilauea

The June 27th lava flow is still advancing albeit slowly. The HVO has said it has continued approximately 350 yards since Wednesday and is currently is 1.2 miles upslope from Apaa St. and 1.9 mils from Pahoa Village Road. Although there is no immediate threat to power lines or our facilities, Hawaii Electric light are closely following the flow and have even began installing heat resistant and dispersive materials around utility poles in the Puna area.

2. Working to protect utilities but wrapping poles in protective materials.

2. Working to protect utilities but wrapping poles in protective materials.

 

Now these are just eruptions I have so far spoken about on this page, but where else is hearing volcanic rumblings…..

Sheveluch

KVERT has reported in the past few weeks, Sheveluch in the Central Kamchatka region, has had ash explosions, incandescence, hot avalanches, as well as fumarolic activity. An ash plumes that rose 11-11.5 km (36,000-37,700 ft) after an explosion on September 24th still lingers. An ash cloud 250 by 207 km drifted NNE and the aviation code remains at orange.

 

Copahue

Sat on the Chile – Argentine boarder, Copahue experienced an intense seismic swarm on September 26th with over 140 long period events being recorded. Web cams show increased emissions; mostly white plumes, with some ash rising 200-500 m drifting SE. The aviation code remains at yellow.

Aira

JMA reported 12 explosions in the last few days of September in Aira Caldera’s Sakurajima volcano ejecting tephra as far as 1,300 m. An explosion on the 28th sent a dense ash plume 3 km in to the air. The alert level remains at 3.

 

Popocatepetl

Continuing emissions of water vapor, gas, and occasional small amounts of ash have occurred from the summit. Incandescence from the crater was observed at night. The Alert Level remained at to Yellow, Phase Two.

 

Santa Maria

On September heavy rainfall triggered a hot lahar that descended the Cabello de Ángel River, a tributary of the Nimá I river drainage on the S flank of Santa María’s Santiaguito lava-dome complex. The lahar carried tree trunks and branches, had a strong sulfur odor, and was 18 m wide and 2 m deep. During 27-28 and 29-30 September lava flows travelled down the S flank and steam plumes rose 400-500 m and drifted 600-800 m SW.

 

These just a small selection of volcanoes world wide which are showing signs of activity. As well as the 8 listed here the Smithonian Institution Global Volcanism Program lists a further 9 which show increased levels of activity thus showing how active the Earth is.

3. GVP map of volcanic activity.

3. GVP map of volcanic activity.

 

 

1. SiO2 Map; http://www.vedur.is/vedur/spar/gasdreifing Accessed 04/10/14

2. Protecting Puna; http://khon2.com/2014/10/03/hawaii-electric-lights-contingency-plans-as-kilauea-lava-approaches/ Accessed 05/10/14

3. GVP Map; http://www.volcano.si.edu/reports_weekly.cfm#vn_300270 Accessed 05/10/14