Digtriad.com: Volcano In Ecuador Erupts Friday
Banos, Ecuador -- Tungurahua Volcano spews ash as high as 10km (33,000-feet) into the air, triggering residents to evacuate and officials to divert flights. Known as "Throat of Fire," Tungurahua is one of eight active volcanos in Ecuador.
Ecuador's "Throat of Fire" volcano erupted today spewing ash that forced hundreds of residents to flee, authorities said.
Loud explosions shook the ground and rattled windows near the volcano, known as Tungurahua in the indigenous Quechua language, 81 miles southeast of Quito, officials said.
Vulcanologist Silvana Hidalgo said scientists are carefully monitoring the situation and have detected a small dip in activity.
"In these last few hours, what we've registered is a small decrease in volcanic activity regarding the energy with which the columns are expelled," she said.
Officials in the area said hundreds of families had evacuated, some voluntarily, while Ecuador's aviation authorities closed the airport in coastal Guayaquil and altered the routes of some flights to avoid the ash cloud.
Baños, a town popular with foreign and local tourists, was among the places evacuated voluntarily, officials said.
Tungurahua, a 16,500 ft volcano, has been classed as active since 1999 and had a strong eruption in 2008. It is one of eight active volcanoes in Ecuador.
Friday, April 29, 2011
Wednesday, April 27, 2011
US advises citizens in Phl not to go to Taal Volcano
PhilStar.com: US advises citizens in Phl not to go to Taal Volcano
MANILA, Philippines (Xinhua) -- The US embassy today advised its travelers in the Philippines to avoid going to Taal Volcano due to high seismic activity in the area.
"The US embassy reminds US citizens that the Philippine government has established that the entire Volcano Island is a Permanent Danger Zone (PDZ) and has stated that permanent settlement in the island is strictly not recommended. No residents are allowed within the danger zone," the embassy said in its warden message.
"US tourists considering travel to the vicinity of the Taal Volcano to strictly observe any Philippine government restrictions on travel into the PDZ and to pay close attention to daily status reports issued by The Philippine Institute of Volcanology and Seismology (PHIVOLCS)," it added.
Taal Volcano, one of the most active volcanoes in the country, is located in the province of Batangas, approximately 60 kilometers south of Manila.
PHIVOLCS maintains alert level 2 over Taal as the magma rises towards the surface of the volcano, as manifested by carbon dioxide being released in the Main Crater Lake and an increase in seismic activity.
PHIVOLCS advises the public that the main crater, Daang Kastila Trail, and Mt. Tabaro are strictly off-limits because sudden hazardous steam-driven explosions may occur and a high concentration of toxic gases may accumulate.
MANILA, Philippines (Xinhua) -- The US embassy today advised its travelers in the Philippines to avoid going to Taal Volcano due to high seismic activity in the area.
"The US embassy reminds US citizens that the Philippine government has established that the entire Volcano Island is a Permanent Danger Zone (PDZ) and has stated that permanent settlement in the island is strictly not recommended. No residents are allowed within the danger zone," the embassy said in its warden message.
"US tourists considering travel to the vicinity of the Taal Volcano to strictly observe any Philippine government restrictions on travel into the PDZ and to pay close attention to daily status reports issued by The Philippine Institute of Volcanology and Seismology (PHIVOLCS)," it added.
Taal Volcano, one of the most active volcanoes in the country, is located in the province of Batangas, approximately 60 kilometers south of Manila.
PHIVOLCS maintains alert level 2 over Taal as the magma rises towards the surface of the volcano, as manifested by carbon dioxide being released in the Main Crater Lake and an increase in seismic activity.
PHIVOLCS advises the public that the main crater, Daang Kastila Trail, and Mt. Tabaro are strictly off-limits because sudden hazardous steam-driven explosions may occur and a high concentration of toxic gases may accumulate.
Orange alert issued in Ecuador, Tungurahua volcano awakens
Buenos Aires Herald: Orange alert issued in Ecuador, Tungurahua volcano awakens
The National Secretary of Risk management in Ecuador, María del Pilar Cornejo declared an orange alert today following the awakening of the Tungurahua volcano last night. Due to the explosions, three local towns have been evacuated.
She mentioned that “security precautions must be taken, following the volcano’s increased activity.”
According to the ministry, on Monday the “increased activity provoked a giant ash cloud reaching 8 kilometres in height,” Ansa agency reported.
The recent eruptions have provoked a declared state of emergency in Ecuador where officials reported they “want to provide help to those living in the volcano-affected area, and particularly help evacuate those in danger zones.”
Cornejo said that the evacuation process of various close by towns and villages has begun, with Cusúa (80 families), Bilbao (30 families and 100 non-permanent residents) and in Chacabuco (30 families), also confirming the closure of local schools.
The Institute of Geophysics at Ecuador’s Polytechnic School, which controls the volcano’s activity, recorded increased activity from April 20, with ash and pyroclastic material blasting from the cone.
According to their most recent report, six moderate to great explosions were recorded, creating the ejection of ash, provoking the giant cloud which reached “up to eight kilometres in height above the crater.”
The Tungurahua, also known as the “Throat of fire” is 5,020 metres above sea level, and is located 130 kilometres southeast of Quito. It has been active since 1999 when volcanic activity restarted, and in 2006 an eruption caused the death of six people.
The National Secretary of Risk management in Ecuador, María del Pilar Cornejo declared an orange alert today following the awakening of the Tungurahua volcano last night. Due to the explosions, three local towns have been evacuated.
She mentioned that “security precautions must be taken, following the volcano’s increased activity.”
According to the ministry, on Monday the “increased activity provoked a giant ash cloud reaching 8 kilometres in height,” Ansa agency reported.
The recent eruptions have provoked a declared state of emergency in Ecuador where officials reported they “want to provide help to those living in the volcano-affected area, and particularly help evacuate those in danger zones.”
Cornejo said that the evacuation process of various close by towns and villages has begun, with Cusúa (80 families), Bilbao (30 families and 100 non-permanent residents) and in Chacabuco (30 families), also confirming the closure of local schools.
The Institute of Geophysics at Ecuador’s Polytechnic School, which controls the volcano’s activity, recorded increased activity from April 20, with ash and pyroclastic material blasting from the cone.
According to their most recent report, six moderate to great explosions were recorded, creating the ejection of ash, provoking the giant cloud which reached “up to eight kilometres in height above the crater.”
The Tungurahua, also known as the “Throat of fire” is 5,020 metres above sea level, and is located 130 kilometres southeast of Quito. It has been active since 1999 when volcanic activity restarted, and in 2006 an eruption caused the death of six people.
Monday, April 25, 2011
Why would you ever bomb a volcano?
Big Think: Why would you ever bomb a volcano?
by Erik Klemetti
There has been some discussion over the years here on Eruptions about what might happen if you were to bomb an eruption volcano. Now, this might be to divert a lava flow, to stop an eruption to prevent an eruption from occurring, but overall, people seem to love the idea that shear human force could prevent a volcanic disaster. Maybe we have Hollywood to blame for this - there are quite a few examples of people putting bombs in volcanoes to start/stop an eruption and hey, it sounds daring. It is the sort of last ditch, hail Mary attempt at averting disaster that makes good (and by that I mean bad) cinema.
So, why am I going to talk about bombing volcanoes? Well, because it is exciting.
First off, I have never heard or could find any evidence of any attempt to bomb a volcano to stop it from erupting - you know, the idea that if you were to bomb it, the volcano would go from looking like it was going to erupt to going back to silence. Not one. Ever. Why? Well, mostly because it would never work. First off, most magmatic systems are kilometers below the surface of the Earth, so to cause any real disruption (and thus prevention of eruption) as to stop an impending eruption, you would need some sort of nuclear device - and even that might be insufficient … and nuking a volcano is kind of like chopping one's finger off to stop a hangnail. If you get it wrong, you're spreading radiation that could be doubly dispersed in volcano ash. No sane geologist would ever advocate such action. Even the so-called "bunker buster" conventional bombs would like not disrupt a magmatic system and, in fact, most likely cause the volcano to erupt, rather than stop it. Remember, once the signs appear that suggest a volcano might erupt, a rapid release of pressure is what is needed to get an explosive eruption to occur, just the sort of thing that bombing a volcano might induce (like a supposed plan to bomb volcanoes in Japan into erupting during World War II).
So, that is off the table. Sorry folks, bombing a volcano isn't going to stop an eruption. Then why bomb a volcano in the first place?
I poked around have found only a very few examples of bombing a volcanic eruption and the United States was involved in every one - at least three times in Hawai`i and once in Italy at Etna. The former was bombing with live ordnance - bombs - while the Etna example was "bombing" with concrete blocks. All of these attempts were to divert flowing lava rather than to stop an eruption.
In the case of Mt. Etna, the bombing occurred during the 1992 activity at the volcano. The lava from the eruption was threatening some important structures on Etna including an astronomical observatory, so a plan was developed to try to divert the lava from the town. Barriers were constructed to keep the lava from flowing into the town - mostly by constructing earthen barriers to keep the lava from heading in the directions that it shouldn't. This had worked before during the 1983 eruptions that Etna and might have saved Italy between $2-22 million dollars - and it was one of the first time that humans were able to actively intervene during a volcanic eruption (along with the successful 1973 diversion at Heimaey in Iceland). In 1992, lava flows threatened Zafferana Etnea, a small town on the flanks of Etna. This time attempts to divert the lava (see above) included dropping concrete blocks on the lava flows so as to block it from flowing towards the town. The plan was to blow a hole in a lava tube at higher elevations and then fill the lava tube with concrete blocks (see below)to stop the flow of lava in the tube. Once lava can move down a lava tube, it is very well insulated - so much so that the lava inside the tube can stay hot and move quickly downslope, to the point where it can actually thermally eroded (melt) the bottom and sides of the lava tube, thus making it bigger. By punching a hole in the tube and filling it with debris, the hope was to stop this from occurring. The "bombing" of the flow was a mixed success - it was unclear how much the diversion actually worked, but the towns were spared - but the question of whether diverting lava flows at Etna is a good idea is still up in the air.
The other example was from Mauna Loa in Hawai`i. Many people forget that the Big Island in Hawai`i is home to not just one active volcano (Kilauea), but three - Hualalai and Mauna Loa (and even Mauna Kea, although it likely hasn't erupted in a few thousand years). In fact, Mauna Loa was very active during the middle of the 20th century and erupted as recently as 1984. Mauna Loa is a much larger threat to the people of the Big Island as well - the northeast Rift Zone of the volcano is close to the city of Hilo (see map below), there have been times when lava flows from Mauna Loa threatened the city, its water supply or ecologically-fragile rain forests on the slopes of the volcano.
Lockwood and Torgerson (1980) is an excellent look at what happens when you try to bomb a volcano with active ordnance to attempt to divert lava flows. In fact, as early as 1881 has the idea of using man-made explosions to stop lava flows been suggested at Mauna Loa. The U.S. has tried to bomb Mauna Loa while it was erupting at least twice in the last 100 years and a series of tests were run in the 1970s to determine the best course of action if lava flows from Mauna Loa threatened Hilo again. Overall, it appears that in limited situations, targeted bombing campaigns on vulnerable parts of the volcano - mainly spatter cones that are the source of lava tubes high on the slopes of Mauna Loa - might cause sufficient diversion as to prevent lava flows from reaching Hilo.
Lockwood and Torgerson (1980) mention two attempts to bomb the volcano while it was actively erupting - once in 1935 (here is some video of that campaign) and once in 1942, during World War II. Both attempts yielding no noticeable results, but some of the evidence of the bombing campaign can still be found in the form of small craters in lava flows (usually less than 10 m across) or in bombs coated in basaltic glass (see below). Now, both of these bombing attempts were performed using antiquated (at the time) bombs, and even though the pilots of the bombers reported "sheets of red, molten rock thrown up 200 feet", the lava flows were unaffected (but both ended relatively soon afterwards by causes unrelated to the bombing). Both of these attempts were centered around the idea that bombing lava tubes could disrupt the flow of lava and force it to exit the tube system far upslope from settlements, thus causing the lava to flow harmless on the volcano's upper flanks.
In the 1970s, some tests were conducted by the U.S. Air Force and HVO scientists to see what might be the most effective means of bombing if the goal is to divert a lava flow. These tests (see image below) were on an older lava field with no active lava flows and were performed using relatively modern (for the 70s) ordnance. What was found was that if you target spatter cones that feed lava tube systems, then lava flow disruption - where the surface was most fragile and not dense, solid rocks like above some lava tubes. Bombing the actual lava tubes or flow levees didn't seem to be very effective. Interestingly, the bombing did show signs of widespread effects, with cracks found in the lava up to 10 meters from the actual crater and disruption of the hardened lava surface as far as 50 meters away.
The study came to some conclusions that I hadn't really considering when it comes to bombing lava flows, especially in Hawai`i. On the plus side, many times lava flows near the summit area at Mauna Loa occur on government lands, so bombing could occur without disruption of private property. Also, bombing the flow to divert lava is a relatively low cost endeavor, especially relative to the cost of lava flows reaching populated area. However, on the negative side, bombing Hawaiian volcanoes is bound to cause native Hawaiians some consternation as the bombing could be perceived as an affront to Pele. In a more practical sense, not all eruptions will have obvious vulnerable spots to bottom and indiscriminate bombing of lava flows could have unintended effects.
There you have it - bombing a volcano to divert lava flows could work - but only if you pick the right place. This isn't a matter of just dropping the largest bomb you can find and hope for the best. In fact, Lockwood and Torgerson (1980) say that lava tube disruption could be accomplished, if the target it picked correctly, with as little as a single 900-kg conventional bomb. This means close cooperation between the military and volcanologists to find the right spot to bomb. It might not be as exciting as racing to get that thermonuclear weapon down the gullet of a volcano in the nick of time to save Seattle from Rainier, but likely a whole lot more effective (in those cases where lava flows are your biggest threat).
Reference:
Lockwood, J.P. and Torgerson, F.A., 1980, Diversion of lava flows by aerial bombing - Lessions from Mauna Loa volcano, Hawaii. Bulletin of Volcanology, vol. 43-4, pp. 727-741.
Top left: Lowering a nuclear bomb into a Pacific volcano in order to start an eruption in 1965's "Crack in the World".
Volcanic ash gets its close-up
Science News: Volcanic ash gets its close-up
The most detailed visual study yet of volcanic ash from last year’s Icelandic eruption reveals just how sharp, abrasive and potentially dangerous the particles were.
After Eyjafjallajökull erupted in April 2010, sending volcanic plumes high into the atmosphere, officials closed Europe’s airspace for days because of the risk of ash scouring planes or being sucked into jet engines and shutting them down. “Aviation authorities made the right decision,” says team leader Susan Stipp, a geoscientist at the University of Copenhagen.
Hours after the volcano began erupting, University of Iceland volcanologists Sigurdur Gíslason and Helgi Alfredsson raced toward it to collect ash. They were the last ones to cross a bridge to safety before meltwater floods from atop Eyjafjallajökull washed the road away.
Gíslason sent some of the fresh ash, along with another batch collected 12 days later, to Stipp, whose lab studies how natural particles flow in the environment. The scientists put the ash through a barrage of tests, like attaching a single particle to the tip of a tiny beam to measure changes in mass. Their results appear the week of April 25 in the Proceedings of the National Academy of Sciences.
As ash particles exit the volcano, volatile gases condense on them and coat them with salts including the elements chlorine, fluorine and arsenic. Stipp and her colleagues dunked the ash particles in water, as might happen in a flood, and watched as tiny bits of salt washed away. In one case, 35 millionths of a millionth of a gram vanished within 15 seconds. Knowing how fast these salts dissolve, Stipp says, can help scientists understand whether the ash is dangerous to drinking water.
The researchers kept washing the ash, but even after being stirred around in water for two weeks it kept its sharp edges, Stipp says. “The particles remain extremely sharp even after they’ve been grinding against each other.”
Ash that was produced right after Eyjafjallajökull exploded on April 14 was more abrasive than the sample collected 12 days later, and was also smaller and more powdery, the team found. Many of the explosive ash bits glommed onto larger particles — suggesting that scientists may have underestimated the fraction made of particles less than 10 micrometers across, a limit often used to mark a breathing hazard.
Other labs could follow the same tests to see how dangerous a particular eruption is, says Stipp.
Another upcoming study supports the idea that Eyjafjallajökull’s ash clumps together. In a paper to appear in Geology, Jacopo Taddeucci of Italy’s National Institute of Geophysics and Volcanology and colleagues describe ash from the final days of the eruption in May 2010. Even then, Eyjafjallajökull was spitting out both sharp, dense fragments and more fragile, irregularly shaped ones, says team member Daniele Andronico, also at the Italian institute.
Ash sometimes clumped together in aggregates, the team found. On hitting the ground, these aggregates broke apart into a cloud of smaller particles, dropping more particles than expected. The research shows that volcanoes don’t always play by the rule book, says Andronico.
The most detailed visual study yet of volcanic ash from last year’s Icelandic eruption reveals just how sharp, abrasive and potentially dangerous the particles were.
After Eyjafjallajökull erupted in April 2010, sending volcanic plumes high into the atmosphere, officials closed Europe’s airspace for days because of the risk of ash scouring planes or being sucked into jet engines and shutting them down. “Aviation authorities made the right decision,” says team leader Susan Stipp, a geoscientist at the University of Copenhagen.
Hours after the volcano began erupting, University of Iceland volcanologists Sigurdur Gíslason and Helgi Alfredsson raced toward it to collect ash. They were the last ones to cross a bridge to safety before meltwater floods from atop Eyjafjallajökull washed the road away.
Gíslason sent some of the fresh ash, along with another batch collected 12 days later, to Stipp, whose lab studies how natural particles flow in the environment. The scientists put the ash through a barrage of tests, like attaching a single particle to the tip of a tiny beam to measure changes in mass. Their results appear the week of April 25 in the Proceedings of the National Academy of Sciences.
As ash particles exit the volcano, volatile gases condense on them and coat them with salts including the elements chlorine, fluorine and arsenic. Stipp and her colleagues dunked the ash particles in water, as might happen in a flood, and watched as tiny bits of salt washed away. In one case, 35 millionths of a millionth of a gram vanished within 15 seconds. Knowing how fast these salts dissolve, Stipp says, can help scientists understand whether the ash is dangerous to drinking water.
The researchers kept washing the ash, but even after being stirred around in water for two weeks it kept its sharp edges, Stipp says. “The particles remain extremely sharp even after they’ve been grinding against each other.”
Ash that was produced right after Eyjafjallajökull exploded on April 14 was more abrasive than the sample collected 12 days later, and was also smaller and more powdery, the team found. Many of the explosive ash bits glommed onto larger particles — suggesting that scientists may have underestimated the fraction made of particles less than 10 micrometers across, a limit often used to mark a breathing hazard.
Other labs could follow the same tests to see how dangerous a particular eruption is, says Stipp.
Another upcoming study supports the idea that Eyjafjallajökull’s ash clumps together. In a paper to appear in Geology, Jacopo Taddeucci of Italy’s National Institute of Geophysics and Volcanology and colleagues describe ash from the final days of the eruption in May 2010. Even then, Eyjafjallajökull was spitting out both sharp, dense fragments and more fragile, irregularly shaped ones, says team member Daniele Andronico, also at the Italian institute.
Ash sometimes clumped together in aggregates, the team found. On hitting the ground, these aggregates broke apart into a cloud of smaller particles, dropping more particles than expected. The research shows that volcanoes don’t always play by the rule book, says Andronico.
Friday, April 22, 2011
Volcanoes in Costa Rica
Costa Rica, officially the Republic of Costa Rica (Spanish: Costa Rica or República de Costa Rica, is a country in Central America, bordered by Nicaragua to the north, Panama to the east and south, the Pacific Ocean to the west and south and the Caribbean Sea to the east
Costa Rica, which means "Rich Coast", constitutionally abolished its army permanently in 1949. It is the only Latin American country included in the list of the world's 22 older democracies. Costa Rica has consistently been among the top Latin American countries in the Human Development Index, ranked 62nd in the world in 2010, and is cited by the UNDP as one of the countries that has attained much higher human development than other countries at the same income levels. The country is ranked 3rd in the world, and 1st among the Americas, in terms of the 2010 Environmental Performance Index.
In 2007 the Costa Rican government announced plans for Costa Rica to become the first carbon neutral country by 2021. According to the New Economics Foundation, Costa Rica ranks first in the Happy Planet Index and is the "greenest" country in the world.
The highest point in the country is Cerro Chirripó, at 3,819 metres (12,530 ft), and is the fifth highest peak in Central America. The highest volcano in the country is the Irazú Volcano (3,431 m or 11,257 ft). The largest lake in Costa Rica is Lake Arenal.
The Irazú Volcano (Spanish: Volcán Irazú) is an active volcano in Costa Rica, situated in the Cordillera Central close to the city of Cartago. Its name could come from either the combination of "ara" (point) and "tzu" (thunder) or a corruption of Iztarú, which was the name of an indigenous village on the flanks of the volcano. In Costa Rica it is known by the name of "El Coloso" (The Colossus) due to the catastrophes that it has provoked in the past.
The volcano's summit has several craters, one of which contains Diego de la Haya, a green crater lake of variable depth. It is the highest active volcano in Costa Rica. It is easily visited from San José, with a road leading right up to the summit craters and a weekly bus service to the top. It is thus a popular tourist spot. The volcano summit also spots a few television transmitters for television stations in San José.
From the top it is possible to see both the Atlantic and Pacific Oceans on a clear day. However, such clear days are very rare indeed, and it is typical for the volcano's summit to be covered in cloud for much of the time.
GeologyThe Irazú volcano is a complex volcanic shield. It is the highest active volcano in Costa Rica, and has an area of 500 km2 (190 sq mi)It has an irregular subconic shape, and its temperature oscillates between 3 °C and 17 °C. It is a stratovolcano with a summit elevation of 3432 metres. Its five craters are easily differentiated.[1] The most important ones, because of their activity, are The Main Crater, which is almost circular has very inclined walls and it measures 1050 meters in diameter and 300 meters depth; The Diego de la Haya crater is 600 meters diameter and 100 meters deep. Other craters are Playa Hermosa, La Laguna, and El Piroclastico.
Irazú is the southernmost of the ten Quaternary volcanoes which form a northwest-trending line through central and northern Costa Rica.[2] Radioactive dating has shown an age of at least 854,000 years with eruption peaks at 570,000 years and the most recent active phase from 136,000 years to present. The most recent activity includes lava flows along with strombolian and phreatomagmatic explosions. Lava types include basalt and andesite erupted during different events suggesting the volcano is fed by two distinct magma chambers.
Eruptive history
Irazú has erupted frequently in historical times — at least 23 times since its first historically recorded eruption in 1723. Its most famous recent eruption began in 1963 and continued until 1965. It began on the day US President John F. Kennedy started a state visit to Costa Rica and showered the capital San José and much of the central highlands of Costa Rica with ash.[citation needed]
Its historical eruptions generally have VEIs of 1 to 3. All historical eruptions have been explosive, and there have been many phreatic eruptions, and some have produced pyroclastic flows. The latest eruption lasted only 1 day, and occurred on December 8 1994. It occurred at a flank vent and was a phreatic eruption, which produced lahars.
In Spanish: http://www.ovsicori.una.ac.cr/vulcanologia/volcanes/irazu.htm
Costa Rica, which means "Rich Coast", constitutionally abolished its army permanently in 1949. It is the only Latin American country included in the list of the world's 22 older democracies. Costa Rica has consistently been among the top Latin American countries in the Human Development Index, ranked 62nd in the world in 2010, and is cited by the UNDP as one of the countries that has attained much higher human development than other countries at the same income levels. The country is ranked 3rd in the world, and 1st among the Americas, in terms of the 2010 Environmental Performance Index.
In 2007 the Costa Rican government announced plans for Costa Rica to become the first carbon neutral country by 2021. According to the New Economics Foundation, Costa Rica ranks first in the Happy Planet Index and is the "greenest" country in the world.
The highest point in the country is Cerro Chirripó, at 3,819 metres (12,530 ft), and is the fifth highest peak in Central America. The highest volcano in the country is the Irazú Volcano (3,431 m or 11,257 ft). The largest lake in Costa Rica is Lake Arenal.
The Irazú Volcano (Spanish: Volcán Irazú) is an active volcano in Costa Rica, situated in the Cordillera Central close to the city of Cartago. Its name could come from either the combination of "ara" (point) and "tzu" (thunder) or a corruption of Iztarú, which was the name of an indigenous village on the flanks of the volcano. In Costa Rica it is known by the name of "El Coloso" (The Colossus) due to the catastrophes that it has provoked in the past.
The volcano's summit has several craters, one of which contains Diego de la Haya, a green crater lake of variable depth. It is the highest active volcano in Costa Rica. It is easily visited from San José, with a road leading right up to the summit craters and a weekly bus service to the top. It is thus a popular tourist spot. The volcano summit also spots a few television transmitters for television stations in San José.
From the top it is possible to see both the Atlantic and Pacific Oceans on a clear day. However, such clear days are very rare indeed, and it is typical for the volcano's summit to be covered in cloud for much of the time.
GeologyThe Irazú volcano is a complex volcanic shield. It is the highest active volcano in Costa Rica, and has an area of 500 km2 (190 sq mi)It has an irregular subconic shape, and its temperature oscillates between 3 °C and 17 °C. It is a stratovolcano with a summit elevation of 3432 metres. Its five craters are easily differentiated.[1] The most important ones, because of their activity, are The Main Crater, which is almost circular has very inclined walls and it measures 1050 meters in diameter and 300 meters depth; The Diego de la Haya crater is 600 meters diameter and 100 meters deep. Other craters are Playa Hermosa, La Laguna, and El Piroclastico.
Irazú is the southernmost of the ten Quaternary volcanoes which form a northwest-trending line through central and northern Costa Rica.[2] Radioactive dating has shown an age of at least 854,000 years with eruption peaks at 570,000 years and the most recent active phase from 136,000 years to present. The most recent activity includes lava flows along with strombolian and phreatomagmatic explosions. Lava types include basalt and andesite erupted during different events suggesting the volcano is fed by two distinct magma chambers.
Eruptive history
Irazú has erupted frequently in historical times — at least 23 times since its first historically recorded eruption in 1723. Its most famous recent eruption began in 1963 and continued until 1965. It began on the day US President John F. Kennedy started a state visit to Costa Rica and showered the capital San José and much of the central highlands of Costa Rica with ash.[citation needed]
Its historical eruptions generally have VEIs of 1 to 3. All historical eruptions have been explosive, and there have been many phreatic eruptions, and some have produced pyroclastic flows. The latest eruption lasted only 1 day, and occurred on December 8 1994. It occurred at a flank vent and was a phreatic eruption, which produced lahars.
In Spanish: http://www.ovsicori.una.ac.cr/vulcanologia/volcanes/irazu.htm
Travel: The Beautiful Risk of a Volcano
Top News (New Zealand): The Beautiful Risk of a Volcano
Costa Rica is considered as one of the most beautiful places in the world. There have been volcanic activities at the Arenal since July 29, 1968. Costa Rica is counted among the ten most active volcanoes in the world. This volcano is considered to be right at the top of most active volcanoes in the world.
Arenal has a lot to offer for people interested in the beauty of nature. The third smallest strip in the United States of America has the options of Zip lining flights, treetop walks, trekking along the volcanoes, the Caribbean coast with impressive beaches. The required luxurious available for a memorable journey.
It is considered as the ideal journey for the admirers of the nature and the reality of the world. The journey has all the required ingredients of an ideal vacation for the people with the desire nature while being closet to an active volcano permitted by the authorities. There are more than 850 species of birds and 250 species of mammals are found near the volcano.
A person can travel over the unbelievably beautiful landscape beneath the safe 15 cable lines. The entire US$45 (S$56) is worth every penny
Costa Rica is considered as one of the most beautiful places in the world. There have been volcanic activities at the Arenal since July 29, 1968. Costa Rica is counted among the ten most active volcanoes in the world. This volcano is considered to be right at the top of most active volcanoes in the world.
Arenal has a lot to offer for people interested in the beauty of nature. The third smallest strip in the United States of America has the options of Zip lining flights, treetop walks, trekking along the volcanoes, the Caribbean coast with impressive beaches. The required luxurious available for a memorable journey.
It is considered as the ideal journey for the admirers of the nature and the reality of the world. The journey has all the required ingredients of an ideal vacation for the people with the desire nature while being closet to an active volcano permitted by the authorities. There are more than 850 species of birds and 250 species of mammals are found near the volcano.
A person can travel over the unbelievably beautiful landscape beneath the safe 15 cable lines. The entire US$45 (S$56) is worth every penny
Tuesday, April 19, 2011
Forced Evacuations Near Philippines Volcano
Taal Volcano, Lake Taal
IrishWeatherOnline.com: Forced Evacuations Near Philippines Volcano
Residents in Batangas in the Philippines are being urged to evacuate as Volcano Taal looks set to erupt.
The Philippine Institute of Volcanology and Seismology (Phivolcs) said that 21 volcanic earthquakes were recorded around Taal volcano in Batangas province during the past 24 hours. Water temperature at the main crater lake has also slightly increased from 29 degrees Celsius to 30.1 degrees Celsius.
The Philippine authorities will forcibly evacuate residents who refuse to leave the danger zone of the restive Taal volcano, senior government officials warned today.
Taal Volcano is a complex volcano on the island of Luzon in the Philippines. Historical eruptions are concentrated on Volcano Island, an island near the middle of Lake Taal. The lake partially fills Taal Caldera, which was formed by prehistoric very powerful eruptions.
The volcano had several violent eruptions in the past causing loss of life in the island and the populated areas surrounding the lake, with the death toll estimated at around 5,000 to 6,000. Because of its proximity to populated areas and its eruptive history, the volcano was designated a Decade Volcano, worthy of close study to prevent future natural disasters. It is one of the active volcanoes in the Philippines and part of the Pacific ring of fire.
Monday, April 18, 2011
Inter-Korean volcano talks 'premature': Seoul official
THe Straits Times (Singapore): Inter-Korean volcano talks 'premature': Seoul official
JEJU - IT IS 'premature' for the two Koreas to hold governmental talks for a joint survey of a North Korean mountain to assess the risk of its potential volcanic eruption, a high-level Seoul official said on Sunday.
The remark came days after the two Koreas agreed to conduct a joint on-site survey of Mount Baekdu during a rare civilian-led meeting that experts say may help open the way for official dialogue between the two countries.
'We cannot rule out a possibility that the experts' meeting could develop further (into an inter-governmental meeting) if it goes well, laying grounds for dialogue. We, however, have no intention to utilize it as a formality to open the dialogue,' the official told reporters on condition of anonymity. 'The ball is in the North's court, not ours. The future of inter-Korean dialogue depends on Pyongyang's attitude.'
Mount Baekdu, the highest mountain on the Korean Peninsula, has been dormant since its last eruption in 1903, but experts have warned that it may still have an active core, citing topographical signs and satellite images.
The official also said that South Korea can send more civilian aid to the vulnerable in the North if transparent distribution can be ensured.
He, however, reaffirmed that his government has no immediate plan to send massive rice shipments to North Korea by saying, 'There is no change in the present government position.' -- THE KOREA HERALD/ANN
JEJU - IT IS 'premature' for the two Koreas to hold governmental talks for a joint survey of a North Korean mountain to assess the risk of its potential volcanic eruption, a high-level Seoul official said on Sunday.
The remark came days after the two Koreas agreed to conduct a joint on-site survey of Mount Baekdu during a rare civilian-led meeting that experts say may help open the way for official dialogue between the two countries.
'We cannot rule out a possibility that the experts' meeting could develop further (into an inter-governmental meeting) if it goes well, laying grounds for dialogue. We, however, have no intention to utilize it as a formality to open the dialogue,' the official told reporters on condition of anonymity. 'The ball is in the North's court, not ours. The future of inter-Korean dialogue depends on Pyongyang's attitude.'
Mount Baekdu, the highest mountain on the Korean Peninsula, has been dormant since its last eruption in 1903, but experts have warned that it may still have an active core, citing topographical signs and satellite images.
The official also said that South Korea can send more civilian aid to the vulnerable in the North if transparent distribution can be ensured.
He, however, reaffirmed that his government has no immediate plan to send massive rice shipments to North Korea by saying, 'There is no change in the present government position.' -- THE KOREA HERALD/ANN
Philippines' Taal Volcano shows new life
CNN World: Philippines' Taal Volcano shows new life
(CNN) -- Volcanologists in the Philippines are closely monitoring a volcano on Luzon Island close to the capital, Manila, after a sudden spike in seismic activity.
Twenty one volcanic earthquakes were recorded at Taal Volcano from Sunday 8 a.m. to Monday 8 a.m.
One of the earthquakes was felt by local residents in Brgy Calauit at the southeast side of the island.
Scientists at the Philippine Institute of Volcanology and Seismology (PHIVOLCS) say the quakes are an indication that magma is moving towards Taal's surface.
The main crater lake has been heating up since January.
PHIVOLCS Science Research Specialist Alex Ramos told CNN that scientists have seen "a slight intensification of steaming in the main crater lake."
He said emissions of carbon dioxide have risen from 1,875 tons per day in February to 4,670 tons at the end of March.
PHIVOLCS has raised its five step alert level to 2 around Taal and is warning people not to go near the crater lake or main Daang Kastila Trail due to the high concentration of toxic gases and a risk of steam explosions.
The popular tourist attraction is 65 kilometres (40 miles) south of the Manila.
An estimated 7,000 people live on the volcanic island which last erupted in 1977.
(CNN) -- Volcanologists in the Philippines are closely monitoring a volcano on Luzon Island close to the capital, Manila, after a sudden spike in seismic activity.
Twenty one volcanic earthquakes were recorded at Taal Volcano from Sunday 8 a.m. to Monday 8 a.m.
One of the earthquakes was felt by local residents in Brgy Calauit at the southeast side of the island.
Scientists at the Philippine Institute of Volcanology and Seismology (PHIVOLCS) say the quakes are an indication that magma is moving towards Taal's surface.
The main crater lake has been heating up since January.
PHIVOLCS Science Research Specialist Alex Ramos told CNN that scientists have seen "a slight intensification of steaming in the main crater lake."
He said emissions of carbon dioxide have risen from 1,875 tons per day in February to 4,670 tons at the end of March.
PHIVOLCS has raised its five step alert level to 2 around Taal and is warning people not to go near the crater lake or main Daang Kastila Trail due to the high concentration of toxic gases and a risk of steam explosions.
The popular tourist attraction is 65 kilometres (40 miles) south of the Manila.
An estimated 7,000 people live on the volcanic island which last erupted in 1977.
Friday, April 15, 2011
Indonesia: Volcano's victims still unable to rebuild
Spero News: Indonesia: Volcano's victims still unable to rebuild
Mount Merapi erupted in November 2010. More and more people living on the slopes of the volcano have lost their homes due to the destructive force known as 'cold lava' where volcanic ash, stones and other material are brought down the mountain by the rivers.
Six months after the initial eruption, Indonesia's most active volcano still prevents people from returning home and rebuilding their lives on the dangerous slopes of Mount Merapi.
One of the most active of the 129 volcanoes in Indonesia, the November 2010 eruption of Mount Merapi caused the deaths of 322 people and led to the displacement of another 136,585. After the eruptions, more and more people living on the slopes of the volcano have lost their homes due to the destructive force known as 'cold lava' where volcanic ash, stones and other material are brought down the mountain by the rivers.
In addition to the 100,000 people who lost their homes to the volcanic eruption, a further approximately 3,750 were newly displaced as a consequence of the eruption's aftershock, cold lava. Shortly after the eruption in late October, JRS responded to the natural disaster providing emergency assistance in some of the 13 government-managed camps.
JRS provided food, medicine, sleeping mats, sanitary products and clothing through distribution points for displaced persons living outside of the official camps and directly to people sheltered in surrounding villages. With the help of 177 volunteers JRS assisted 75,957 IDPs and returnees during the initial four months.
The JRS response to the crisis has focused on providing to the most vulnerable displaced persons and offering support where other NGOs and governmental agencies were not present.
Follow-up advocacy
Although the government-established temporary shelters are located outside the evacuation zone – a safe distance from the volcano – thousands of people fled to surrounding villages and were taken in by locals. While many villagers said they were happy to assist those displaced, it was apparent they did not have the capacity or income to care for them.
Even though the JRS Indonesia emergency response has come to an end, staff continue to stay in contact with the displaced population there and share information on their needs and concerns in local coordination meetings with authorities.
Mount Merapi erupted in November 2010. More and more people living on the slopes of the volcano have lost their homes due to the destructive force known as 'cold lava' where volcanic ash, stones and other material are brought down the mountain by the rivers.
Six months after the initial eruption, Indonesia's most active volcano still prevents people from returning home and rebuilding their lives on the dangerous slopes of Mount Merapi.
One of the most active of the 129 volcanoes in Indonesia, the November 2010 eruption of Mount Merapi caused the deaths of 322 people and led to the displacement of another 136,585. After the eruptions, more and more people living on the slopes of the volcano have lost their homes due to the destructive force known as 'cold lava' where volcanic ash, stones and other material are brought down the mountain by the rivers.
In addition to the 100,000 people who lost their homes to the volcanic eruption, a further approximately 3,750 were newly displaced as a consequence of the eruption's aftershock, cold lava. Shortly after the eruption in late October, JRS responded to the natural disaster providing emergency assistance in some of the 13 government-managed camps.
JRS provided food, medicine, sleeping mats, sanitary products and clothing through distribution points for displaced persons living outside of the official camps and directly to people sheltered in surrounding villages. With the help of 177 volunteers JRS assisted 75,957 IDPs and returnees during the initial four months.
The JRS response to the crisis has focused on providing to the most vulnerable displaced persons and offering support where other NGOs and governmental agencies were not present.
Follow-up advocacy
Although the government-established temporary shelters are located outside the evacuation zone – a safe distance from the volcano – thousands of people fled to surrounding villages and were taken in by locals. While many villagers said they were happy to assist those displaced, it was apparent they did not have the capacity or income to care for them.
Even though the JRS Indonesia emergency response has come to an end, staff continue to stay in contact with the displaced population there and share information on their needs and concerns in local coordination meetings with authorities.
Thursday, April 14, 2011
Volcanoes and greenhouse gasses
KOLD News 13: Volcanoes and greenhouse gasses
People who are fortunate enough to live in or visit Hawai`i, or even those who have seen the right television documentaries know that the majestic presence of erupting volcanoes attests to their raw power.
Don't try this trick at home, but if we took Kilauea (our own backyard volcano) and collected the lava that it erupted, just during the time it took you to read this sentence, there would be enough material to fill the gas tanks of about 1,000 Sport Utility Vehicles (SUVs.) And though Kilauea is a medium-to-small-sized volcano, it has been discharging lava nearly continuously at this rate for the past 24 years.
Demonstrations like this one, or catastrophic eruptions like those of Mount St. Helens or Mount Pinatubo, understandably cause people to sometimes think that human-caused effects on the biosphere are small compared to volcanic ones. But, as the saying goes, "it ain't necessarily so."
At HVO, for instance, we are often asked about the influence of volcanic gas emissions on the atmosphere and whether these emissions dwarf those from human activity. Anyone who has stood downwind of Kilauea's vents, and sometimes even people who live in Honolulu, 250 miles away, know first-hand how these emissions can affect air quality and life on the regional scale. It's a fact that Kilauea has been releasing more than twice the amount of noxious sulfur dioxide gas (SO2) as the single dirtiest power plant on the U.S. mainland.
So it's also understandable that, with the emerging report of the Intergovernmental Panel on Climate Change (IGCC), some people want to understand how volcanoes might factor into the rise in greenhouse gas concentrations-specifically carbon dioxide (CO2)-that is being reported worldwide. The changes in global CO2 concentration during the past 600,000 years have mimicked the changes in global temperature. And, after all, volcanoes are awesome natural forces that release lots of carbon dioxide (CO2) right? Could volcanoes be a significant global-warming villain?
For numerous reasons, volcanologists have been interested in CO2 release from volcanoes for years and have been working to improve estimates on the amount of CO2 entering the atmosphere and oceans by volcanic processes.
Carbon dioxide is released when magma rises from the depths of the Earth on its way to the surface. Our studies here at Kilauea show that the eruption discharges between 8,000 and 30,000 metric tonnes of CO2 into the atmosphere each day. Actively erupting volcanoes release much more CO2 than sleeping ones do.
Gas studies at volcanoes worldwide have helped volcanologists tally up a global volcanic CO2 budget in the same way that nations around the globe have cooperated to determine how much CO2 is released by human activity through the burning of fossil fuels. Our studies show that globally, volcanoes on land and under the sea release a total of about 200 million tonnes of CO2 annually.
This seems like a huge amount of CO2, but a visit to the U.S. Department of Energy's Carbon Dioxide Information Analysis Center (CDIAC) website (http://cdiac.ornl.gov/) helps anyone armed with a handheld calculator and a high school chemistry text put the volcanic CO2 tally into perspective. Because while 200 million tonnes of CO2 is large, the global fossil fuel CO2 emissions for 2003 tipped the scales at 26.8 billion tonnes. Thus, not only does volcanic CO2 not dwarf that of human activity, it actually comprises less than 1 percent of that value.
A short time ago (geologically speaking) the question "Which produces more CO2, volcanic or human activity?" would have been answered differently. Volcanoes would have tipped the scale. Now, human presence, activity, and the resultant production of CO2, through the burning of fossil fuels, have all climbed at an ever-increasing rate. On the other hand, looking back through the comparatively short duration of human history, volcanic activity has, with a few notable disturbances, remained relatively steady.
Volcanoes are still awesome, even though they don't produce CO2 at a rate that swamps the human signature, contributing to global warming. In fact, spectacular eruptions like that of Mount Pinatubo are demonstrated to contribute to global cooling through the injection of solar energy reflecting ash and other small particles.
There is now agreement at the top government level of the Earth's most prolific fossil fuel CO2 producer-the United States-that we need to reduce our dependence on oil in order to confront the challenge of global warming. As we work toward that goal, let's look forward to the day when volcanologists will give a different answer to the question "Which produces more CO2, volcanic or human activity?"
People who are fortunate enough to live in or visit Hawai`i, or even those who have seen the right television documentaries know that the majestic presence of erupting volcanoes attests to their raw power.
Don't try this trick at home, but if we took Kilauea (our own backyard volcano) and collected the lava that it erupted, just during the time it took you to read this sentence, there would be enough material to fill the gas tanks of about 1,000 Sport Utility Vehicles (SUVs.) And though Kilauea is a medium-to-small-sized volcano, it has been discharging lava nearly continuously at this rate for the past 24 years.
Demonstrations like this one, or catastrophic eruptions like those of Mount St. Helens or Mount Pinatubo, understandably cause people to sometimes think that human-caused effects on the biosphere are small compared to volcanic ones. But, as the saying goes, "it ain't necessarily so."
At HVO, for instance, we are often asked about the influence of volcanic gas emissions on the atmosphere and whether these emissions dwarf those from human activity. Anyone who has stood downwind of Kilauea's vents, and sometimes even people who live in Honolulu, 250 miles away, know first-hand how these emissions can affect air quality and life on the regional scale. It's a fact that Kilauea has been releasing more than twice the amount of noxious sulfur dioxide gas (SO2) as the single dirtiest power plant on the U.S. mainland.
So it's also understandable that, with the emerging report of the Intergovernmental Panel on Climate Change (IGCC), some people want to understand how volcanoes might factor into the rise in greenhouse gas concentrations-specifically carbon dioxide (CO2)-that is being reported worldwide. The changes in global CO2 concentration during the past 600,000 years have mimicked the changes in global temperature. And, after all, volcanoes are awesome natural forces that release lots of carbon dioxide (CO2) right? Could volcanoes be a significant global-warming villain?
For numerous reasons, volcanologists have been interested in CO2 release from volcanoes for years and have been working to improve estimates on the amount of CO2 entering the atmosphere and oceans by volcanic processes.
Carbon dioxide is released when magma rises from the depths of the Earth on its way to the surface. Our studies here at Kilauea show that the eruption discharges between 8,000 and 30,000 metric tonnes of CO2 into the atmosphere each day. Actively erupting volcanoes release much more CO2 than sleeping ones do.
Gas studies at volcanoes worldwide have helped volcanologists tally up a global volcanic CO2 budget in the same way that nations around the globe have cooperated to determine how much CO2 is released by human activity through the burning of fossil fuels. Our studies show that globally, volcanoes on land and under the sea release a total of about 200 million tonnes of CO2 annually.
This seems like a huge amount of CO2, but a visit to the U.S. Department of Energy's Carbon Dioxide Information Analysis Center (CDIAC) website (http://cdiac.ornl.gov/) helps anyone armed with a handheld calculator and a high school chemistry text put the volcanic CO2 tally into perspective. Because while 200 million tonnes of CO2 is large, the global fossil fuel CO2 emissions for 2003 tipped the scales at 26.8 billion tonnes. Thus, not only does volcanic CO2 not dwarf that of human activity, it actually comprises less than 1 percent of that value.
A short time ago (geologically speaking) the question "Which produces more CO2, volcanic or human activity?" would have been answered differently. Volcanoes would have tipped the scale. Now, human presence, activity, and the resultant production of CO2, through the burning of fossil fuels, have all climbed at an ever-increasing rate. On the other hand, looking back through the comparatively short duration of human history, volcanic activity has, with a few notable disturbances, remained relatively steady.
Volcanoes are still awesome, even though they don't produce CO2 at a rate that swamps the human signature, contributing to global warming. In fact, spectacular eruptions like that of Mount Pinatubo are demonstrated to contribute to global cooling through the injection of solar energy reflecting ash and other small particles.
There is now agreement at the top government level of the Earth's most prolific fossil fuel CO2 producer-the United States-that we need to reduce our dependence on oil in order to confront the challenge of global warming. As we work toward that goal, let's look forward to the day when volcanologists will give a different answer to the question "Which produces more CO2, volcanic or human activity?"
Wednesday, April 13, 2011
Iceland’s Volcano: One Year Later
The Epoch Times: Iceland’s Volcano: One Year Later
Last April, Iceland’s Eyjafjallajökull volcano eruption was an economic and logistical nightmare for the millions of travelers in Europe. But one year later, European Union officials say they are amply prepared if the volcano—or one like it—blows again.
Even though “volcanoes and other aviation crises are by their nature unpredictable,” the EU has made headway in putting systems in place to prevent another travel disaster, said European Commission Vice-President Siim Kallas.
Eyjafjallajökull continuously spewed out a miasma of ash for more than a month, resulting in the cancellation of roughly 100,000 flights, at a cost to the airline industry of about estimated $1.7 billion.
The troublesome volcano is now completely dormant and on April 14, which marks the one-year anniversary of the day it first erupted, a small visitor center is being opened for tourists—yes, tourists.
Those who wish to see source of the economic destruction that was wrought upon Europe can book a flight on Iceland Express, which is now capitalizing on last year's ordeal.
The main reason for the canceled flights was fear that large plumes of ash would clog airplane engines. The measure was mainly taken as a precaution since the airlines were not clear on the extent of the danger.
The EU said that airline engine manufacturers will now have to, by law, “provide detailed information about risk associated with volcanic ash exposure and tolerance levels of the different engines they produce.”
This fall, the EU said it will use this information to come up with a proposal to require engine manufacturers to tell airlines the risks associated with volcanic ash getting sucked into their engines.
Other systems that will also be put in place include better meteorological systems and new radar systems for enhanced modeling and thus, greater accuracy and prediction.
Such models can provide “accurate, timely and consistent information about the position, amount, composition, altitude, projected trajectory, and drift of volcanic ash,” the EU stated.
Last April, Iceland’s Eyjafjallajökull volcano eruption was an economic and logistical nightmare for the millions of travelers in Europe. But one year later, European Union officials say they are amply prepared if the volcano—or one like it—blows again.
Even though “volcanoes and other aviation crises are by their nature unpredictable,” the EU has made headway in putting systems in place to prevent another travel disaster, said European Commission Vice-President Siim Kallas.
Eyjafjallajökull continuously spewed out a miasma of ash for more than a month, resulting in the cancellation of roughly 100,000 flights, at a cost to the airline industry of about estimated $1.7 billion.
The troublesome volcano is now completely dormant and on April 14, which marks the one-year anniversary of the day it first erupted, a small visitor center is being opened for tourists—yes, tourists.
Those who wish to see source of the economic destruction that was wrought upon Europe can book a flight on Iceland Express, which is now capitalizing on last year's ordeal.
The main reason for the canceled flights was fear that large plumes of ash would clog airplane engines. The measure was mainly taken as a precaution since the airlines were not clear on the extent of the danger.
The EU said that airline engine manufacturers will now have to, by law, “provide detailed information about risk associated with volcanic ash exposure and tolerance levels of the different engines they produce.”
This fall, the EU said it will use this information to come up with a proposal to require engine manufacturers to tell airlines the risks associated with volcanic ash getting sucked into their engines.
Other systems that will also be put in place include better meteorological systems and new radar systems for enhanced modeling and thus, greater accuracy and prediction.
Such models can provide “accurate, timely and consistent information about the position, amount, composition, altitude, projected trajectory, and drift of volcanic ash,” the EU stated.
Monday, April 11, 2011
Yellowstone volcanic plume much larger than expected
Ars Technica: Yellowstone volcanic plume much larger than expected
Yellowstone National Park hosts a variety of hot springs and geysers, all powered by a plume of molten rock under its surface. At times in the past, that plume has powered activity that was quite a bit less scenic: massive eruptions that have been capable of covering roughly half of North America with ash. Thus, understanding the structure and evolution of this hotspot has an immense practical value. Now, thanks to an array of sensors funded by the National Science Foundation and some new computing techniques, some researchers have produced a new image of the plume, one that suggests the area of elevated temperatures is much larger than previously suspected.
Yellowstone sits on the same sort of mantle plume that powers the Hawaiian volcanoes. Since it's located in the middle of a continental plate, however, the behavior is quite different. Instead of relatively steady flows of molten rock, mid-continent hotspots tend to produce rare, explosive eruptions. Yellowstone's major eruptions have been separated by hundreds of thousands of years, and have packed an astonishing punch, with each eruption being thousands of times more potent than Mt. St. Helens.
Past imaging efforts have used seismic waves to detect the border between molten and solid rock. These have indicated that the mantle plume originates somewhere deep under Idaho and slopes eastward as it rises to meet the surface under Wyoming.
The new picture roughly agrees with this, but suggests the area heated by the plume may be far more extensive than indicated by the seismic data. It relies on what is termed magneto-telluric (MT) readings, which register subtle changes in the Earth's conductivity and magnetic fields. These register differences in temperature and composition of the rock and fluids, as these change alter the conductivity of the crust.
MT data was a bit hard to come by, but the National Science Foundation's Earth Scope grid has produced readings from a regularly spaced network of sensors across the western US. The authors were able to get readings from hundreds of stations across most of Idaho, Montana, and Wyoming to image the plume underneath Yellowstone.
Converting subtle differences in conductivity into a detailed map of underground structures is a rather complicated task, and a large portion of the paper is devoted to describing the computational methods that made it possible. Most of these involved adapting known solutions so that they could be run in parallel and lowering the memory requirements for the production of a single volume of the Earth's crust. Both the generation of the cells used (which were 4km on a side) and the calculations themselves were parallelized, allowing the reconstruction to be run on a computing grid in a reasonable amount of time.
The resulting picture suggests that the molten rock of the mantle plume seen in seismic images is only the core of a much larger volume of hot crust. Although this area isn't molten, the high temperatures allow water to pick up elevated levels of salt, which enables its detection through the MT monitoring equipment. The plume itself seems to slope down a bit more gently, and extend much further under Idaho than the seismic data had suggested. The MT data also confirms suggestions that the rock within the plume doesn't become molten until it reaches a depth of about 250km.
The new data provides an alternate view of the mantle plume that powers Yellowstone, one that adds to the picture painted by existing seismic data. And the techniques developed here should be applicable to other areas of the US West as more data from the Earth Scope grid becomes available.
Yellowstone National Park hosts a variety of hot springs and geysers, all powered by a plume of molten rock under its surface. At times in the past, that plume has powered activity that was quite a bit less scenic: massive eruptions that have been capable of covering roughly half of North America with ash. Thus, understanding the structure and evolution of this hotspot has an immense practical value. Now, thanks to an array of sensors funded by the National Science Foundation and some new computing techniques, some researchers have produced a new image of the plume, one that suggests the area of elevated temperatures is much larger than previously suspected.
Yellowstone sits on the same sort of mantle plume that powers the Hawaiian volcanoes. Since it's located in the middle of a continental plate, however, the behavior is quite different. Instead of relatively steady flows of molten rock, mid-continent hotspots tend to produce rare, explosive eruptions. Yellowstone's major eruptions have been separated by hundreds of thousands of years, and have packed an astonishing punch, with each eruption being thousands of times more potent than Mt. St. Helens.
Past imaging efforts have used seismic waves to detect the border between molten and solid rock. These have indicated that the mantle plume originates somewhere deep under Idaho and slopes eastward as it rises to meet the surface under Wyoming.
The new picture roughly agrees with this, but suggests the area heated by the plume may be far more extensive than indicated by the seismic data. It relies on what is termed magneto-telluric (MT) readings, which register subtle changes in the Earth's conductivity and magnetic fields. These register differences in temperature and composition of the rock and fluids, as these change alter the conductivity of the crust.
MT data was a bit hard to come by, but the National Science Foundation's Earth Scope grid has produced readings from a regularly spaced network of sensors across the western US. The authors were able to get readings from hundreds of stations across most of Idaho, Montana, and Wyoming to image the plume underneath Yellowstone.
Converting subtle differences in conductivity into a detailed map of underground structures is a rather complicated task, and a large portion of the paper is devoted to describing the computational methods that made it possible. Most of these involved adapting known solutions so that they could be run in parallel and lowering the memory requirements for the production of a single volume of the Earth's crust. Both the generation of the cells used (which were 4km on a side) and the calculations themselves were parallelized, allowing the reconstruction to be run on a computing grid in a reasonable amount of time.
The resulting picture suggests that the molten rock of the mantle plume seen in seismic images is only the core of a much larger volume of hot crust. Although this area isn't molten, the high temperatures allow water to pick up elevated levels of salt, which enables its detection through the MT monitoring equipment. The plume itself seems to slope down a bit more gently, and extend much further under Idaho than the seismic data had suggested. The MT data also confirms suggestions that the rock within the plume doesn't become molten until it reaches a depth of about 250km.
The new data provides an alternate view of the mantle plume that powers Yellowstone, one that adds to the picture painted by existing seismic data. And the techniques developed here should be applicable to other areas of the US West as more data from the Earth Scope grid becomes available.
Mount Etna volcano calms down
UPI.com: Mount Etna volcano calms down
CATANIA, Italy, April 11 (UPI) -- Italian officials said 11,000-foot-tall Mount Etna, one of the most active volcanoes in the world, has calmed down after two days of activity.
But volcano experts said in an ANSA report Monday that Europe's tallest active volcano might have fallen back into a short-lived slumber and another "active phase may just be around the corner."
On Sunday, the volcano blasted lava and shards of magma more than 1,200 feet into the air and a plume of black smoke rose more than 2 miles above the crater.
The wind carried fragments of the eruption to towns southeast of the large eastern Sicilian city of Catania but flight operations at the city's airport were unaffected, the report said.
CATANIA, Italy, April 11 (UPI) -- Italian officials said 11,000-foot-tall Mount Etna, one of the most active volcanoes in the world, has calmed down after two days of activity.
But volcano experts said in an ANSA report Monday that Europe's tallest active volcano might have fallen back into a short-lived slumber and another "active phase may just be around the corner."
On Sunday, the volcano blasted lava and shards of magma more than 1,200 feet into the air and a plume of black smoke rose more than 2 miles above the crater.
The wind carried fragments of the eruption to towns southeast of the large eastern Sicilian city of Catania but flight operations at the city's airport were unaffected, the report said.
Residents refuse to leave their homes near Taal volcano
GulfNews: Residents refuse to leave their homes near Taal volcano
Manila: Only 388 of 7,000 residents have left their homes near the simmering Taal volcano in southern Luzon's Batangas province.
A total of 81 families or 388 people from four villages were evacuated, and a majority of them were housed at Venancio Senior Memorial School while the rest stayed with their relatives when the volcano's lips fluted and its surrounding lake registered high carbon dioxide, said Jing Segismundo, provincial information officer.
Some 1,552 families or 6,612 residents who refused to leave their homes were instructed to prepare to leave since the entire volcano island is a danger zone.
The National Disaster Risk Reduction and Management Council alerted all local government units to prepare for enforced evacuation.
Toxic gases
The Philippine Institute of Volcanology and Seismology (Phivolcs) said people should be barred from going to Taal's main crater, Daang Kastila Trail and Mt Tabaro because "sudden hazardous steam-driven explosions could occur and high concentrations of toxic gases may accumulate".
On Monday, Taal's main crater registered seven volcanic earthquakes, a decrease from 21 tremors on Friday. But its lips began to inflate, compared to a survey measurement on February 2.
The lake around it emitted 4,670 tonnes of carbon dioxide on Sunday, compared to an earlier measurement of 2,250 tonnes per day. The lake was also less acidic, with pH value of 2.84 compared to 2.82 on March 29. All these are signs that magma has been rising near Taal's crater.
More than 30 eruptions
Earthquakes and carbon dioxide emissions could increase in the next several days, a sign of the volcano's "magmatic eruption," said Phivolcs, but no date was specified for the major eruption.
Taal has erupted 33 times. Its last eruption was in 1977. Many lives were saved then because lava flows stopped at the lake surrounding the volcano. The Philippines has 22 active volcanoes.
Manila: Only 388 of 7,000 residents have left their homes near the simmering Taal volcano in southern Luzon's Batangas province.
A total of 81 families or 388 people from four villages were evacuated, and a majority of them were housed at Venancio Senior Memorial School while the rest stayed with their relatives when the volcano's lips fluted and its surrounding lake registered high carbon dioxide, said Jing Segismundo, provincial information officer.
Some 1,552 families or 6,612 residents who refused to leave their homes were instructed to prepare to leave since the entire volcano island is a danger zone.
The National Disaster Risk Reduction and Management Council alerted all local government units to prepare for enforced evacuation.
Toxic gases
The Philippine Institute of Volcanology and Seismology (Phivolcs) said people should be barred from going to Taal's main crater, Daang Kastila Trail and Mt Tabaro because "sudden hazardous steam-driven explosions could occur and high concentrations of toxic gases may accumulate".
On Monday, Taal's main crater registered seven volcanic earthquakes, a decrease from 21 tremors on Friday. But its lips began to inflate, compared to a survey measurement on February 2.
The lake around it emitted 4,670 tonnes of carbon dioxide on Sunday, compared to an earlier measurement of 2,250 tonnes per day. The lake was also less acidic, with pH value of 2.84 compared to 2.82 on March 29. All these are signs that magma has been rising near Taal's crater.
More than 30 eruptions
Earthquakes and carbon dioxide emissions could increase in the next several days, a sign of the volcano's "magmatic eruption," said Phivolcs, but no date was specified for the major eruption.
Taal has erupted 33 times. Its last eruption was in 1977. Many lives were saved then because lava flows stopped at the lake surrounding the volcano. The Philippines has 22 active volcanoes.
Volcano Glossary - the B's
Basalt - a dark-colored, fine-grained lava rich in iron and magnesium and relatively poor in silica (less than 54 percent.) The most common of earth's volcanic rocks, basaltic lavas compose all the ocean floors and many continental formations as well. Typically very fluid because of their low silica content, basaltic lavas can flow great distances from their source, forming broad lava plains such as the Columbia River Plateau. Shield volcanoes are typically formed exclusively of basalt.
Bergschrund - A Crevass at the back of a glacier between the glacier and its rock headwall, formed by partial melting and movement of the glacier. [A German word. Berg= mountain. Schrund = crevass.
Block - Angular fragment of lava rock measuring a minimum of 2.5 inches to several tens of feet in diameter.
Block-and-ash flow - Variety of a pyroclastic flow, a turbulent mass of hot dense rock fragments that avalanches downslopes as the result of an eruption. Block-and-ash flows are commonly triggered by the distruption or collapse of a dome while hot.
Blocky lava - A lava flow whose surface is characterized by a jumble of large angular blocks.
Bomb - a lump of plastic or molten lava thrown out during an explosive eruption. Bombs range in size from 2.5 inches to many feet in diameter. Because of their plastic condition when first ejected, bombs are commonly modified in shape during their flight through the air and/or by ther impact on the ground. As the outer crust cools and solidifies, continued expansion of the interior by gas pressure sometimnes causes cracking, which may form a bomb surface resembling the crust of freshly baked bread (breadcrust bombs).
Breccia - Rock composed of many distinct fragments, typically sharp and/or angular, embedded in a matrix of fine material. Breccias are sometimes formed when shattered lava blocks are transported by avalanches or mudflows.
Bergschrund - A Crevass at the back of a glacier between the glacier and its rock headwall, formed by partial melting and movement of the glacier. [A German word. Berg= mountain. Schrund = crevass.
Block - Angular fragment of lava rock measuring a minimum of 2.5 inches to several tens of feet in diameter.
Block-and-ash flow - Variety of a pyroclastic flow, a turbulent mass of hot dense rock fragments that avalanches downslopes as the result of an eruption. Block-and-ash flows are commonly triggered by the distruption or collapse of a dome while hot.
Blocky lava - A lava flow whose surface is characterized by a jumble of large angular blocks.
Bomb - a lump of plastic or molten lava thrown out during an explosive eruption. Bombs range in size from 2.5 inches to many feet in diameter. Because of their plastic condition when first ejected, bombs are commonly modified in shape during their flight through the air and/or by ther impact on the ground. As the outer crust cools and solidifies, continued expansion of the interior by gas pressure sometimnes causes cracking, which may form a bomb surface resembling the crust of freshly baked bread (breadcrust bombs).
Breccia - Rock composed of many distinct fragments, typically sharp and/or angular, embedded in a matrix of fine material. Breccias are sometimes formed when shattered lava blocks are transported by avalanches or mudflows.
Saturday, April 9, 2011
Phivolcs: Earthquakes rock Taal, Bulusan Volcanoes
MB.Com.PH (Manilla): Phivolcs: Earthquakes rock Taal, Bulusan Volcanoes
MANILA, Philippines -- Taal Volcano rocked nine times Friday while Mt. Bulusan had three earthquakes in the past 24 hours ending at 8 a.m. yesterday, the Philippine Institute of Volcanology and Seismology (Phivolcs) said.
Phivolcs said Taal is still under Alert Level 1 and warned residents not to venture into the main crater since carbon dioxide emissions may be fatal in spite of the findings that steaming activity at the thermal area was weak.
Water level dipped from 0.36 meter to 0.33 meter but water temperature slightly increased from 30.0°C to 30.5°C and pH value also slightly increased to 2.84 as compared to the last reading of 2.82 on March 29, meaning the water became slightly less acidic.
But no imminent eruption is forecast.
On the other hand, Mt. Bulusan recorded only three volcanic earthquakes until early morning yesterday and the emission of white smoke was weak at the southeast and northwest thermal vents.
Measurements of sulphur dioxide (SO2) emission rate showed a decline to 28 tons per day (tpd) as of April 6, compared to the previous reading of 38 tpd the previous day.
Bulusan Volcano’s status remains at Alert Level 1 and entry to the four-kilometer radius Permanent Danger Zone (PDZ) is strictly prohibited.
Civilian aircraft are also warned not to venture close to the volcano’s summit as ejected ash and volcanic fragments from sudden explosions may be hazardous to aircraft.
Mayon Volcano emitted only moderate levels of steam yesterday and Alert Level 1 is in effect in the area.
No eruption is imminent, according to Phivolcs, but the public should not enter the six-kilometer radius PDZ due to the continuing threat from sudden small explosions and rockfalls from the upper and middle slopes of the volcano.
MANILA, Philippines -- Taal Volcano rocked nine times Friday while Mt. Bulusan had three earthquakes in the past 24 hours ending at 8 a.m. yesterday, the Philippine Institute of Volcanology and Seismology (Phivolcs) said.
Phivolcs said Taal is still under Alert Level 1 and warned residents not to venture into the main crater since carbon dioxide emissions may be fatal in spite of the findings that steaming activity at the thermal area was weak.
Water level dipped from 0.36 meter to 0.33 meter but water temperature slightly increased from 30.0°C to 30.5°C and pH value also slightly increased to 2.84 as compared to the last reading of 2.82 on March 29, meaning the water became slightly less acidic.
But no imminent eruption is forecast.
On the other hand, Mt. Bulusan recorded only three volcanic earthquakes until early morning yesterday and the emission of white smoke was weak at the southeast and northwest thermal vents.
Measurements of sulphur dioxide (SO2) emission rate showed a decline to 28 tons per day (tpd) as of April 6, compared to the previous reading of 38 tpd the previous day.
Bulusan Volcano’s status remains at Alert Level 1 and entry to the four-kilometer radius Permanent Danger Zone (PDZ) is strictly prohibited.
Civilian aircraft are also warned not to venture close to the volcano’s summit as ejected ash and volcanic fragments from sudden explosions may be hazardous to aircraft.
Mayon Volcano emitted only moderate levels of steam yesterday and Alert Level 1 is in effect in the area.
No eruption is imminent, according to Phivolcs, but the public should not enter the six-kilometer radius PDZ due to the continuing threat from sudden small explosions and rockfalls from the upper and middle slopes of the volcano.
Philippine volcano alert level raised
Google News: Philippine volcano alert level raised
MANILA — Magma rising to the surface of a volcano on a popular island close to the Philippine capital prompted the government to push up its alert level and urge visitors to stay away.
The second stage of a five-step alert system has been imposed around Taal Volcano, a visitor spot located 65 kilometres (40 miles) south of Manila, after increased signs of activity were detected.
While this does not mean an eruption is imminent, government volcano monitoring officer Julio Sabit said tourists and residents were warned to steer clear of Taal's crater and from thermal vents on its northern side.
"It is still a grey area. We still cannot say if it will culminate in an eruption," Sabit told AFP on Saturday.
The volcano could suffer intensified activity but could also slowly subside as it did last year, after showing increasing activity in June, Sabit said.
Taal is one of the most unstable of the country's 22 known active volcanoes with 33 recorded eruptions, the last one in 1977.
A lake surrounding the crater prevented deaths in 1977 and during other eruptions, as the body of water protected outlying areas from the lava.
MANILA — Magma rising to the surface of a volcano on a popular island close to the Philippine capital prompted the government to push up its alert level and urge visitors to stay away.
The second stage of a five-step alert system has been imposed around Taal Volcano, a visitor spot located 65 kilometres (40 miles) south of Manila, after increased signs of activity were detected.
While this does not mean an eruption is imminent, government volcano monitoring officer Julio Sabit said tourists and residents were warned to steer clear of Taal's crater and from thermal vents on its northern side.
"It is still a grey area. We still cannot say if it will culminate in an eruption," Sabit told AFP on Saturday.
The volcano could suffer intensified activity but could also slowly subside as it did last year, after showing increasing activity in June, Sabit said.
Taal is one of the most unstable of the country's 22 known active volcanoes with 33 recorded eruptions, the last one in 1977.
A lake surrounding the crater prevented deaths in 1977 and during other eruptions, as the body of water protected outlying areas from the lava.
Wednesday, April 6, 2011
Oregon volcano to be monitored
UPI.com: Oregon volcano to be monitored
BEND, Ore., April 5 (UPI) -- The U.S. Geological Survey says it wants to monitor a volcano in Eastern Oregon to record any future rumblings of activity as soon as possible.
The Newberry volcano, about 20 miles southeast of Bend, will get eight seismic and GPS monitoring stations under a USGS proposal, the East Oregonian reported Wednesday.
"We're doing this on Newberry because it's a potentially active volcano," John Ewert at the Cascades Volcano Observatory in Vancouver, Wash., said.
"And as far as volcanoes go, it's one that, were it to reactivate, we'd be pretty concerned about because there are substantial numbers of people and infrastructure nearby."
The seismometers can detect earthquakes caused when magma moves below the surface, and the GPS will signal changes in the shape of the surface that could be caused by the shifting magma below, Ewert said.
There is currently one seismic detector on the volcano, but to detect the exact location of cracking or fracturing rock signaling a possible eruption requires at least four, he said.
Nine stations is something of a minimal number for a volcano the size of Newberry, he said, and can measure its normal behavior on a day-to-day basis.
With the last eruption just 1,300 years ago -- relatively recently, geologically speaking -- volcanologists say the more measurements, the better.
"It's just a big honking volcano," Cynthia Gardner with the Cascades observatory said, "and it deserves more than we have on it right now."
BEND, Ore., April 5 (UPI) -- The U.S. Geological Survey says it wants to monitor a volcano in Eastern Oregon to record any future rumblings of activity as soon as possible.
The Newberry volcano, about 20 miles southeast of Bend, will get eight seismic and GPS monitoring stations under a USGS proposal, the East Oregonian reported Wednesday.
"We're doing this on Newberry because it's a potentially active volcano," John Ewert at the Cascades Volcano Observatory in Vancouver, Wash., said.
"And as far as volcanoes go, it's one that, were it to reactivate, we'd be pretty concerned about because there are substantial numbers of people and infrastructure nearby."
The seismometers can detect earthquakes caused when magma moves below the surface, and the GPS will signal changes in the shape of the surface that could be caused by the shifting magma below, Ewert said.
There is currently one seismic detector on the volcano, but to detect the exact location of cracking or fracturing rock signaling a possible eruption requires at least four, he said.
Nine stations is something of a minimal number for a volcano the size of Newberry, he said, and can measure its normal behavior on a day-to-day basis.
With the last eruption just 1,300 years ago -- relatively recently, geologically speaking -- volcanologists say the more measurements, the better.
"It's just a big honking volcano," Cynthia Gardner with the Cascades observatory said, "and it deserves more than we have on it right now."
Tuesday, April 5, 2011
The Hot Seat: A Photographer's Descent Into A Volcano
NPR: The Hot Seat: A Photographer's Descent Into A Volcano
According to his own website, Photographer Carsten Peter "specializes in going to extremes," and his recent National Geographic adventures are no exception: For the magazine's April issue, he descended into the depths of one of the world's most dangerous — and least studied — volcanoes, Nyiragongo.
This active volcano rises up above the war-torn city of Goma in Democratic Republic of the Congo, which is home to an estimated one million people. Volcanologist Dario Tedesco says in the article, "there is no question the volcano will erupt again, potentially transforming Goma into a modern Pompeii." How to predict when this might happen is the crucial question the scientists hope to figure out.
The team of scientists set up camp only a few hundred feet above the giant lake of lava. I spoke with Peter on the phone and he says that the inside of a volcano is a "magic place to be" but it does not come without risk, e.g., falling rocks, splattering lava and poisonous gases seeping out of every crack. "It's like a big cat-and-mouse game where you don't want to be caught."
You can see their entire journey into Nyiragongo on the National Geographic Channel special Man Vs. Volcano. And check out more of Peter's volcano (and tornado!) photos on his site. http://www.carstenpeter.com/en/volcanoes.html
Sunday, April 3, 2011
Kilauea’s effect on Earth’s crust to be observed with special radar
Star Advertsier.com: Kilauea’s effect on Earth’s crust to be observed with special radar
NASA will begin a nine-day mission tomorrow using special radar to study the eruption of Kilauea volcano.
A NASA Gulfstream III aircraft with specialized instrumentation from the Dryden Aircraft Operations Facility in Palmdale, Calif., will be using an “interferometric synthetic aperture radar” developed by NASA’s Jet Propulsion Laboratory in Pasadena, Calif.
The Uninhabited Aerial Vehicle Synthetic Aperture Radar sends pulses of microwave energy from the aircraft to the ground to detect and measure subtle deformations in Earth’s surface, such as those caused by earthquakes, volcanoes, landslides and glacier movements.
As the airplane flies at an altitude of about 41,000 feet, the radar, located in a pod under its belly, will collect data over Kilauea, a NASA news release said.
The radar’s first data acquisitions over this volcanic region took place in January 2010, when the radar was flown over the volcano daily for a week. The UAVSAR detected deflation of Kilauea’s caldera over one day, part of a series of deflation-inflation events as magma was pumped into the volcano’s east rift zone.
Next week’s flights will repeat the 2010 flight paths to an accuracy of within 5 meters, or about 16.5 feet, assisted by a Platform Precision Autopilot designed by engineers at NASA’s Dryden Flight Research Center on Edwards Air Force Base, Calif. Comparing these images forms interferograms that reveal changes in Earth’s surface.
NASA will begin a nine-day mission tomorrow using special radar to study the eruption of Kilauea volcano.
A NASA Gulfstream III aircraft with specialized instrumentation from the Dryden Aircraft Operations Facility in Palmdale, Calif., will be using an “interferometric synthetic aperture radar” developed by NASA’s Jet Propulsion Laboratory in Pasadena, Calif.
The Uninhabited Aerial Vehicle Synthetic Aperture Radar sends pulses of microwave energy from the aircraft to the ground to detect and measure subtle deformations in Earth’s surface, such as those caused by earthquakes, volcanoes, landslides and glacier movements.
As the airplane flies at an altitude of about 41,000 feet, the radar, located in a pod under its belly, will collect data over Kilauea, a NASA news release said.
The radar’s first data acquisitions over this volcanic region took place in January 2010, when the radar was flown over the volcano daily for a week. The UAVSAR detected deflation of Kilauea’s caldera over one day, part of a series of deflation-inflation events as magma was pumped into the volcano’s east rift zone.
Next week’s flights will repeat the 2010 flight paths to an accuracy of within 5 meters, or about 16.5 feet, assisted by a Platform Precision Autopilot designed by engineers at NASA’s Dryden Flight Research Center on Edwards Air Force Base, Calif. Comparing these images forms interferograms that reveal changes in Earth’s surface.
Subscribe to:
Posts (Atom)