Saturday, November 24, 2007
Can scientific calculations predict lava flow's path?
The lava flow emerging from a crack near Kupaianaha built itself a huge channel raised above the surrounding terrain, a kind of mile-long elevated lava flume system 120 feet above ground level when the eruption began.
Scientists say this kind of perched lava channel has never been seen before, and experts can't predict what will happen next.
The stakes are high.
The fissure is 11 miles from Pahoa Village, and has been pumping out an average of 500,000 cubic meters per day since the July 21 fissure eruption began east of Pu'u 'O'o. The channel has been directing that lava toward the northeast, in the general direction of Pahoa and rural subdivisions that surround the town.
The fissure and channel system have extended flow fingers as far as 3 1/2 miles to the northeast, but each time the flow has stalled well short of any populated areas. Pahoa Village is 700 feet above sea level, and the stop-and-go flow activity has been centered at the 1,800- to 2,200-foot elevation level, and eight to nine miles from the town.
Last week, the flows advanced downhill to just below the 1,700-foot level in the Wao Kele O Puna rain forest, but it appeared possible the flow would stall again because the lava tube feeding it seemed to be blocked.
This Kilauea eruption began more than 24 years ago, and most of its lava flows have moved southeast down the south face of the rift zone often continuing toward the ocean.
The lava has covered about 29,000 acres and burned 189 homes and other buildings including Kalapana Village, but the vast majority of the flows have moved through unpopulated areas. No buildings have burned since 2002.
NEW TOOLS AVAILABLE
The current eruption is different because it has been channeled generally to the north and northeast. Residents and civil defense officials have been monitoring where the lava would have to cross to reach Pahoa and Highway 130. The goal is to predict the lava's likely path if the flow becomes more focused and begins moving in a single direction.
One tool scientists have now that was not available when Kalapana was destroyed in 1990 is geographic information software that allows scientists to develop digital elevation models to calculate likely paths that lava may follow.
Maps generated from the data show how fluids such as water would drain across the topography, and two tests by Hawai'i scientists suggest that data is a reasonably good predictor of how lava flows over the same terrain.
Jim Kauahikaua, scientist-in-charge at the U.S. Geological Survey's Hawaiian Volcano Observatory, said the first test used the data to predict how lava would flow from a Mauna Loa eruption, and then compared that with how 'a'a lava had actually moved toward Hilo on Mauna Loa's Northeast Rift Zone during the 1984 eruption.
The result was encouraging, with the flows following the predicted paths more than 60 percent of the time, Kauahikaua said.
A second test was tried at Kilauea volcano during what was known as the "Mother's Day" flow in 2002 down the west side of the Kilauea flow field.
The U.S. Park Service wanted to create fire breaks to protect critical native forest from fires started by the lava, and wanted the best information available on where the lava would likely go to put the fire breaks in the right places.
USGS used the data to compute flow paths in that area "and again, it was a very good indicator of where the flows were going," Kauahikaua said. "In general, these flows as they crossed the pali especially, they were right on the money in that same direction, and our computed flow paths were all pretty close together in there."
LAVA'S NOT LIKE WATER
Predicting the likely flow paths in the Puna area between Kupaianaha and Pahoa is more difficult because the slopes there tend to be gradual, making it less obvious which way lava will move. USGS now hopes to use much more detailed Light Detection and Ranging, or LiDAR, data collected on the Wao Kele O Puna rain forest to recalculate likely flow paths for the area.
Another problem is that lava doesn't move quite like water. A lava flow may be moving downhill and abruptly stop and harden because of an interruption at the magma source. The cooled lava may then present an obstacle to future flows, causing the next flow to veer off in another direction.
Perhaps the most striking feature of the fissure eruption is the impressive elevated channel that was created by the flow, and has now become a flumelike system for transporting lava northeast from the fissure near Kupaianaha toward Pahoa.
The channel was created when 'a'a cooled and slowed at the end of a lava steam, creating a blockage that caused the stream to back up. The steam then overflowed onto its banks in layers that quickly cooled, and the cooling lava on the banks built up the sides of the channel.
This process has been repeated over and over. Each time the flow out of the mile-long channel is obstructed, molten lava backs up, spills over the sides and hardens, scientists said. Each overflow builds the sides of the structure higher.
TO DIVERT OR NOT?
The channel is now perched about 40 yards high above the original level of the original terrain, and is still routing lava to the northeast.
Several times since August, the sides of the channel have broken and allowed lava to spill out, but the channel always repairs itself, scientists said. Hardened chunks of cooled lava that drop back into the lava stream are carried along until they pile up at the breaches in the channel and plug them up.
However, since the channel is above the surrounding terrain and is directing lava toward a population center, some have wondered if it might be possible to deliberately breach the channel and divert the flow if it threatens the village or highway.
Kauahikaua said that what it would take to breach the channel, and where the ideal place would be to make the breach to steer lava away from populated areas, are questions for civil defense officials and engineers.
Civil Defense Administrator Troy Kindred sees several problems, and said the possibility of diverting the lava is not being actively pursued. Among other things, consideration would need to be given to the cultural implications for Hawaiians, he said.
"There's a lot more things that influence this decision than what might just appear on the surface," he said. "There's a cultural context, and there's a technical context, and whether or not it will work."
Another issue is if the authorities were successful in diverting the flow and then it damaged homes, the authorities bear responsibility for the damage.
Big Island Managing Director Dixie Kaetsu agreed that "diversion is not something that is actively being considered as feasible."
Saturday, November 17, 2007
Russian volcano lost part of its dome
"The analysis of information, received during research of Bezymyanniy held recently showed that the latest eruption of the volcano on November 5 was caused not by movement of scorching magma masses in the entrails of the volcano, but collapse of the slope," the leading research assistant of the Institute of volcanology and seismology of the FEB RAS Aleksey OZEROV reported to the correspondent of RIA Novosti.
According to the scientist, the significant sector of the volcano dome with the total volume of almost 200 thousand cubic meters was demolished. Simultaneously fragment avalanche almost three kilometers long fell down from the slope of the volcano.
In the last years Bezymyanniy was one of the most predictable of 28 acting volcanoes of Kamchatka. Eruptions happened with a permanent interval of 5-6 months and were predicted with high accuracy of probability - up to 100%. And now almost a month passed between eruptions, registered on October 14 and November 5. Activation of the volcano became a complete surprise for the scientists.
"It is possible to establish change of dynamics of eruptions of the volcano Bezymyanniy and necessity of more careful study of its activity," OZEROV thinks.
Bezymyanniy (its height is 2869 meters) is not dangerous for the settlements of the peninsula. At the same time ash loops, saturated with small parts of magma material with the diameter of up to two millimeters, can threaten aviation. The volcanic ashes can cause poisoning of people and animals.
Yellowstone super volcano is on the rise!
The current uplift was detected by a global positioning system stations and radar instruments on an orbiting satellite. The reason for the inflation of the park's surface is due to an infusion of magma about six miles (10 kilometres) underground. But that is because Yellowstone is situated on a giant, geologically active feature known as a supervolcano.
"It's hundreds of times bigger than Mount St. Helens," said Robert Smith, a geophysics professor at the University of Utah. Mount St. Helens is an active volcano in Washington State. "The land is rising because magma and hydrothermal fluids are migrating into the volcano's underground chambers," explained Smith. "It's really kind of a sponge, where you have interlaced open spaces with magma and solid rock between. Only 10% [of the chambers are] actually made up of molten rock," he added. Much of the park sits in a caldera, or crater, some 40 miles (70 kilometres) across, which formed when the cone of the massive volcano collapsed in a titanic eruption 640,000 years ago.
According to Kenneth Pierce of the US Geological Survey in Bozeman, Montana, "The newly detected upswell is part of a natural cycle that is common to calderas." "That's because the Yellowstone caldera has inflated and deflated about six to eight times without a volcanic eruption since the last 14,000 years ago," said Montana. "Since calderas go up and down, we use the term 'restless' to describe these systems," said Smith. The super volcano has produced three large blasts in the past two million years, with 30 smaller eruptions since the caldera formed.
The volcano's most recent flare-up was 70,000 years ago, and volcanic heat continues to fuel the park's famous geysers and hot springs. Many scientists believe the volcano is produced by a "hot spot" in the Earth's mantle, a plume of hot rock rising from hundreds of miles below. "Since the hot spot first rose 16 million years ago, it has produced at least 140 eruptions throughout the north-western United States," said Smith.
"But, there's no evidence of an imminent eruption or hydrothermal explosion," he added. "To gauge any future volcanic activity, the park is continuously monitored by instruments associated with the Yellowstone Volcano Observatory," said Smith. "These provide information of public safety, daily and in real time," he added.
Indonesia is currently facing new possible volcano eruptions
Even on its quiet side, the black sand on the now-forbidden island is so hot that a visitor can only briefly set foot on it.
This week's display by Anak Krakatau — or "Child of Krakatau" — is impressive, yet it is a mere sneeze when compared to the blast in August 1883 that obliterated its "father" in the most powerful explosion in recorded history.
That blast was heard as far away as 2,500 miles and choked the atmosphere with ash and dust, altering weather patterns for years. Some 36,000 people were killed in the eruptions and ensuing tsunamis.
Now the 985-foot peak growing from the ocean where Krakatau once stood is erupting, one of several Indonesian volcanoes that have roared to life in recent weeks.
They illustrate the awesome seismic forces at work deep below the surface of this island nation.
No lives have been lost in the latest round of activity, but thousands of villagers have been evacuated from the slopes of Mount Kelud on Java island. On Thursday, its alert status was dropped a level, meaning it is still dangerous, but residents can return home.
Indonesia's history is studded with seismic events. The 2004 Asian tsunami was spawned by a monster quake off the west coast, which sits at the intersection of three tectonic plates that form one border of the "Pacific Ring of Fire."
The plates — each moving at about the speed a fingernail grows each year — slide against or under each other, allowing molten rock from the Earth's mantle to break the surface via a volcano, or create energy released in an earthquake.
The country's 17,000 islands are home to about 70 active volcanoes, the most in the world.
Twenty of them are on Java, an island roughly the same size as Mississippi, and is home to more than half of the country's 235 million people. With demand for farmable land at a premium, many people choose to live within the shadow of the volcanoes because of the rich volcanic soil that is especially good for crops.
"We have lived here for generations. The land is my life," said Meseman, a 74-year-old papaya farmer on the slopes of Mount Kelud, who like many Indonesians uses only a single name and declined to heed the warnings to leave the area. "It is impossible for me leave. If anything, the volcanic ash will make my fields more fertile."
The cataclysmic eruption of Krakatau — which actually lies west of Java in the Sunda Strait, contrary to the title of the popular 1969 movie, "Krakatoa, East of Java" — followed several months of gradually increasing activity.
Anak Krakatau rose from the sea in 1930 and has been growing ever since.
Visitors can reach the island in about two hours by motor boat from the northern coast of Java, which is a 2 1/2-hour drive from Indonesia's capital, Jakarta. When it is quiet, it is a short, but steep walk to the top of the sandy peak.
When Anak began erupting last week, officials declared a no-go zone of about two miles. But the captain of a boat agreed to take an Associated Press reporter and photographer to Anak, briefly landing on the side of the volcano that was not erupting.
The ground was hot and appeared to vibrate beneath the pumice stone, a volcanic rock that floats on water.
Despite the history of its father, Anak is not considered especially dangerous — for now.
It has settled into a pattern of a gentle eruption every seven or eight years, scientists said.
"Maybe in hundreds of years it will blow, but I will be long gone by then," said Cahya Patria, among the scientists at the Center for Vulcanology and Geological Hazard Mitigation who keep watch on the mountain from a hill on the mainland.
Krakatau is only just visible from their station, so the staff members monitor it with a seismograph and an array of other equipment installed on its slopes, including a camera that takes photos posted on the center's Web site.
As the volcano keeps up a steady stream of thunderous explosions, scientists at the station log each eruption and its intensity.
Visitors to Anak from Jakarta normally pass through the resort towns of Anyer and Carita, which were devastated by the series of tsunamis triggered by the 1883 eruption. There are few signs of that horror, aside from the foundations of a Dutch-built lighthouse that was scythed down by the sea.
The park where its replacement now stands is a popular meeting point for young lovers, who sit on benches straining to catch a glimpse of Anak Krakatau as it billows mushroom clouds of smoke into the sunset.
While most Indonesians are Muslims, many also follow pre-Islamic animist beliefs and worship ancient spirits. Often at full moons, people trek to crater rims and throw in rice, jewelry or live animals to appease the volcanoes.
"The Javanese see nature as a friend because it gives then food and life," said Bagong Suyanto, a professor of rural sociology at the University of Surabaya. "They trust it, they do not see it as a threat like volcanologists do."
Thursday, November 08, 2007
Indonesia lowered Mt. Kelud's alert level
"The alert is downgraded to the second highest due to less intense activity," said Umar Rosadi, a volcanology centre official monitoring Kelud."People are advised to return to their homes but it isn't impossible that there could be a sudden increase in the intensity of activities. People must be ready to be evacuated again."An estimated 350,000 people live within 10 km (6 miles) of the volcano, which is about 90 km southwest of Surabaya, Indonesia's second-largest city and one of its busiest airports.
The 1,731-metre (5,700-foot) volcano spewed ash about 500 metres into the air on Sunday, a day after confusion over whether it had already started erupting.Officials at the volcanology centre said on Saturday that the volcano had erupted while hidden by heavy cloud cover, but later they said that an eruption had not in fact taken place.Kelud, also known as Kelut, means "sweeper" in Javanese, a reference to the fact that when it erupts, it sweeps away everything in its path.
When it last erupted in 1990 at least 30 people were killed, while about 5,000 died in 1919 when it spewed scalding water from its crater lake.Indonesia has the highest number of active volcanoes of any country, sitting on a belt of intense seismic activity known as the "Pacific Ring of Fire".
Mt. Kelud finally erupts!
The mountain is located in the heart of Indonesia's densely populated island of Java. It has been on its highest alert status for more than two weeks and thousands already have been evacuated from villages closest to the crater.But officials say most of the 100,000-plus people living in areas considered to be risk never left or have returned to their homes.
In the last 48 hours, underground tremors have grown more intense and the temperature of the volcano's crater lake has spiked.In 1919, a powerful explosion destroyed dozens of villages and killed more than 5,000 people.Indonesia has about 100 active volcanos, more than any other nation.
Saturday, November 03, 2007
Indonesian volcano eruption is imminent
"It could erupt now," the head of Indonesia's centre for Vulcanology and Geological Hazard Mitigation told Reuters on Friday.
An Indonesian soldier carries an elderly refugee into a camp in Blitar. Police went door to door on Thursday and used megaphones to order villagers near the volcano to flee to tent camps Surono, who only goes by one name, told the news agency from the capital Jakarta that Kelud was in a "critical phase."
An estimated 350,000 people live within 10 kilometres of the volcano, according to Reuters.
Two weeks ago, authorities ordered more than 100,000 people to evacuate vulnerable areas, but many ignored the order to leave or left then returned to tend to their farms, reports said.
Intense seismic activity has increased over the course of the past few days, with analysts recording more than 600 tremors on Thursday night and more than 500 again overnight.
The volcano is only about 90 kilometres away from Surabaya, the second-largest city in the southeast Asian country.
The last time Mount Kelud erupted, in 1990, it killed more than 30 people and injured hundreds of others.
An underground reservoir of magma is pushing up to the surface, but is being blocked by sediment from the 1990 eruption, scientist Mohammed Hendrasto said. That intense pressure could result in "the most horrifying eruption in Kelud's history," he said.
Indonesia, which has about 100 active volcanoes spread across 17,500 islands, sits on the so-called "Ring of Fire" — a series of fault lines stretching from the Western Hemisphere through Japan and Southeast Asia.
High alert prompts evacuation of 100,000 Indonesians due to possible volcano eruption
Mount Kelud in densely populated East Java has been rumbling for the past two weeks, with vulcanologists recording hundreds of deep tremors.
Authorities ordered an evacuation of a 10-kilometre danger zone around the mountain after alert levels were raised to maximum last month, but many residents never left or have since returned to their homes.
Some of those who refused to move out were asked to sign a statement saying they would not seek compensation funds if they were injured or lost family members due to an eruption.
In 1990, an eruption of Kelud killed more than 30 people and injured hundreds. An earlier eruption in 1919 destroyed dozens of villages and killed at least 5,160.
A senior government vulcanologist said the 1,731-metre volcano became active on Thursday, its crater lake bubbling and becoming the hottest since last month's high alert.
Tens of thousands of people have been ordered to evacuate the danger zone [Reuters]Umar Rosadi, part of a team of 16 scientists monitoring the peak, said the intensity and frequency of the Kelud's tremors had already exceeded those before the previous eruption in 1990.
"The activity of volcanic tremor is increasing," he said, adding that magma was 700 metres below the crater and could shoot out if it had enough energy.
Scientists fear that if the magma hits the water inside the crater lake, a giant explosion could occur, sending water, mud and ash careering down the side of the mountain.
Indonesia, which has around 100 active volcanoes spread across 17,500 islands, sits on a seismic belt known as the 'Pacific Rim of Fire' – a series of fault lines stretching from the western hemisphere through Japan and Southeast Asia.
Indonesian officials were also closely monitoring three other volcanoes for increased activity.
Bubbles of gas in Kelud's crater lake are a suresign of an eruption, scientists sayThe second-highest alert has been issued for Mount Anak Krakatau, which sits in the Sunda Strait between Java and Sumatra islands, and has been spewing ash for several days.
Saut Simatupang, of Indonesia's Volcanology and Geological Hazard Mitigation, said increased activity on Anak Krakatau posed a big danger and people have been advised to stay out of a three-kilometre danger zone.
Simatupang also warned that thousands were at risk in West Java from volcanic lahar on Mount Guntur as dams built to collect the material on the slopes start to overflow following heavy rains.
Lahar is a mixture of mud and volcanic lava.
"The volcano is active but there's no increased intensity. What we are concerned [with] is a possible flow of lahar from the dams," he said. "We already issued a recommendation for evacuation two weeks ago."
The 2,249-metre volcano, which lies 200km southeast of Jakarta, is popular with tourists for its hot springs and waterfalls.
Alerts have also been issued for Mount Soputan, in North Sulawesi, which erupted last week spewing columns of ash 1,000-metres high, and Mount Karangetang off the island.
Are volcano eruptions responsible for dinosaurs' extinction?
"It's the first time we can directly link the main phase of the Deccan Traps to the mass extinction," said Princeton University paleontologist Gerta Keller. The main phase of the Deccan eruptions spewed 80 percent of the lava which spread out for hundreds of miles. It is calculated to have released ten times more climate altering gases into the atmosphere than the nearly concurrent Chicxulub meteor impact, according to volcanologist Vincent Courtillot from the Physique du Globe de Paris.
Keller's crucial link between the eruption and the mass extinction comes in the form of microscopic marine fossils that are known to have evolved immediately after the mysterious mass extinction event. The same telltale fossilized planktonic foraminifera were found at Rajahmundry near the Bay of Bengal, about 1000 kilometers from the center of the Deccan Traps near Mumbai.
At Rajahmundry there are two lava "traps" containing four layers of lava each. Between the traps are about nine meters of marine sediments. Those sediments just above the lower trap, which was the mammoth main phase, contain the incriminating microfossils.
Previous work had first narrowed the Deccan eruption timing to within 800,000 years of the extinction event using paleomagnetic signatures of Earth's changing magnetic field frozen in minerals that crystallized from the cooling lava. Then radiometric dating of argon and potassium isotopes in minerals narrowed the age to within 300,000 years of the 65-million-year-old Cretaceous-Tertiary (a.k.a. Cretaceous-Paleogene) boundary, sometimes called the K-T boundary.
The microfossils are far more specific, however, because they demonstrate directly that the biggest phase of the eruption ended right when the aftermath of the mass extinction event began. That sort of clear-cut timing has been a lot tougher to pin down with Chicxulub-related sediments, which predate the mass extinction.
"Our results are consistent and mutually supportive with a number of new studies, including Chenet, Courtillot and others (in press) and Jay and Widdowson (in press), that reveal a very short time for the main Deccan eruptions at or near the K-T boundary and the massive carbon dioxide and sulfur dioxide output of each major eruption that dwarfs the output of Chicxulub," explained Keller. "Our K-T age control combined with these results strongly points to Deccan volcanism as the likely leading contender in the K-T mass extinction." Keller's study was funded by the National Science Foundation.
The Deccan Traps also provide an answer to a question on which Chicxulub was silent: Why did it take about 300,000 years for marine species to recover from the extinction event? The solution is in the upper, later Deccan Traps eruptions.
"It's been an enigma," Keller said. "The very last one was Early Danian, 280,000 years after the mass extinction, which coincides with the delayed recovery."
Keller and her colleagues are planning to explore the onset of the main phase of Deccan volcanism, that is, the rocks directly beneath the main phase lavas at Rajahmundry. That will require drilling into the Rajahmundry Traps, a project now slated for December-January 2007/2008.
Keller and her collaborator Thierry Adatte from the University of Neuchatel, Switzerland, are scheduled to present the new findings on Tuesday, 30 October, at the annual meeting of the Geological Society of America in Denver. They will also display a poster on the matter at the meeting on Wednesday, 31 October.
Indonesian volcano spews ash
The mountain in the Sunda Strait, 80 miles west of Jakarta, formed after the giant Krakatoa eruption of 1883 that killed tens of thousands of people and was the largest explosion in recorded history.
"Activity at Anak Krakatoa increased yesterday and there were several small eruptions," said Surono, a leading government volcanologist who, like many Indonesians, uses one name. "We have upgraded the alert level to the second highest."
Anak Krakatoa, which means "Child of Krakatoa," is the third volcano to become active in recent weeks in Indonesia, a sprawling nation of more than 17,000 islands. The country has about 150 volcanos along an arc of fault lines called the Pacific "Ring of Fire."
Krakatoa's massive 1883 blast, heard nearly 2,000 miles away in Australia, sent pyroclastic surges of gas and burning ash which, combined with a tsunami, wiped out 165 villages and killed at least 36,417 people. It destroyed two thirds of the island of Krakatoa between Java and Sumatra.
Volcano eruption causes three fatalities!
The Yemeni Coast Guard rescued 21 of the 29 Yemeni military personnel who were on the island when the volcano erupted, but they requested help from a nearby six-ship NATO task force en route to the Suez Canal, according to Ken Allan of the Canadian Navy's HMCS Toronto.
The Canadian ship located the first survivor about five miles off the coast of the volcanic island, Allan told CNN's American Morning.
"We managed to pluck him out of the water, after he'd been in there for quite a long time and moments later, my ship, the HMCS Toronto, picked up another survivor, currently down in sick bay receiving medical care from our doctor aboard," Allan said.
Allan said the ships, still in the area searching Monday afternoon, also recovered two men who did not survive.
Four Yemeni military personnel are still missing, he said, adding that they were on Jazirt Atta-Ir island when the volcano erupted.
The ships were only 26 nautical miles away when the eruption took place. "It was extremely, extremely brilliant, quite bright off the bow," said Allan.
"Of course the closer we got to the area, the brighter it got. We could actually see the lava spouting out. It was quite brilliant, huge smoke, ash going ... up into the sky."
The ships -- part of a six-ship NATO task force en route to the Suez Canal -- were only 26 nautical miles away when the eruption took place.
The island of Jazirt Atta-Ir is located about 85 miles (140 km) from Yemen in the Red Sea.
The flotilla is known as NATO's Standing NATO Maritime Group 1 (SNMG1), which its Web site describes as "a multinational seagoing Force, on task continuously giving NATO the ability to respond quickly and with flexibility to promote NATO's interests anywhere in the world."
Allan said the eruptions continued on Monday.
"There's still lava pouring off the island," he said. "The northern side seems to be completely devastated."
"The southern side seems to be OK, but the northern side is just nothing but red molten lava."
The island is located near a major shipping lane, but had not slowed traffic, Allan said.