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New eruptions from Kilauea volcano in Hawaii

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Hawaii's Kilauea Volcano - Behind the News

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yanjia

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Indonesia’s Mount Agung Eruption Threatens Bali

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Rivers of lava, debris, and mud could be some of the deadly effects of an eruption from Bali’s Mount Agung.

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Breaking Down the Mount Agung Eruption: Daily Planet

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Zafir

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Residents around Bali's Mount Agung have been warned to stay away from river channels surrounding the smoking volcano as small lahars-destructive mud flows or so-called cold lava flows-have started down the slopes of the mountain.

The Yeh Sah River in Rendang district, Karangasem for instance is usually pretty dry, but as of Monday morning, brown mud was observed flowing down the slopes of Mount Agung. The river smelled of sulfur and the lahar, or flow has been sweeping other debris in its path like rocks, tree trunks and soil, along with it, while agricultural land in the area has already reportedly been damaged by the mud.

Guys, stay away drom disaster prone areas of Agung Mount.It is rainy season in Bali so it will increase cold lava due to heavy rains and keep far away from rivers. #disasterawareness #agungmount #bali #stayaware pic.twitter.com/asnEtvzV6F

- BNPB Indonesia (@BNPB_Indonesia) November 27, 2017

"The ash released by Mount Agung was hit by rainwater and has now become mud in the Yeh Sah River," Karangasem Police Supt. I Wayan Gede Ardana told on Monday.

While the flows don't seem too deadly at this time, the Volcanology and Geological Disaster Mitigation Center (PVMBG) says rain will only intensify the lahars around Agung-a big deal since Bali is now entering the rainy season.

"This is a small lahar, where eruption materials are carried by rainwater to the river," PVMBG head, Gede Suantika said on Monday.

"You could say it's lahar because there is a smell of sulfur," said head Rendang Village Mount Agung Post monitor, I Dewa Mertayasa.

According to Mertayasa, PVMBG will investigate further to determine the level of volcanic material content in the flows.

"We have taken samples to first be checked in the laboratory so we can know the level of volcanic material content," he said.

PVMBG is appealing to local residents to stay away from the river flows, which have mainly been observed on the southern slopes of the volcano, coming upstream of Sebudi Village.

Though additional reports from Bali Post show that Ban, a village on the northern slopes of Agung has also been experiencing flows.

People caught in lahars can drown or be buried, cautions a video produced by VolFlim, a partnership of volcanologists and filmmakers, profiling the volcanic phenomenon. Lahars can move rapidly and occur immediately after an eruption or even weeks or years after and can sweep away structures like bridges and houses.

Lahar Impacts#Agung #Bali https://t.co/4WRxOgJAGx

- Dr Janine Krippner (@janinekrippner) November 27, 2017

"I ask that residents be aware of the lahars along the river coming from Mount Agung. Although the pyroclastic volume of Mount Agung's eruption has not been much," National Disaster Mitigation Agency (BNPB) spokesman Sutopo Purwo Nugroho said in a statement.

Waspadai banjir lahar hujan (lahar dingin) di sekitar Gunung Agung. Banjir lahar hujan sudah terjadi di beberapa tempat di lereng Gunung Agung. Hujan akan meningkat. Jangan melakukan aktivitas di sekitar sungai. Radius 8-10 km harus kosong dari aktivitas masyarakat. #Bali pic.twitter.com/5vuZ4KTTYa

- Sutopo Purwo Nugroho (@Sutopo_BNPB) November 27, 2017

As of Monday morning, the exclusion zone around Mount Agung has been extended to a radius of eight to 10 kilometers from the volcano's crater, as the alert status for a larger eruption was raised to the highest level.

Local residents have been asked to evacuate the exclusion zone but do so in a calm and orderly fashion.

Meanwhile, the airport has been shutdown for at least 24 hours.

The volcano is located in Karangasem, far from the island's tourist hub of Kuta (approximately 75 kilometers) and those outside the exclusion zone are urged to remain calm and "not to panic."

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Bali residents urged to beware of lahars, destructive mud flows, following Agung eruption | Coconuts

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Residents around Bali's Mount Agung have been warned to stay away from river channels surrounding the smoking volcano as small lahars-destructive mud flows or so-called cold lava flows-have started down the slopes of the mountain.

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https://docs.google.com/document/d/1gnYpWc5cIu1kRaCNv6wBHCpdmJWBZOwBpBtHacagxTs/edit

Jia yi

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PINATUBO

According to volcanodiscovery.com: "Prior to the eruption, Pinatubo was a little known volcano. There were no known historic eruptions. Before the eruption in 1991 Pinatubo was 1745 meters high (about 250 meters more than now), and was only 200 meters higher than the nearby peaks, which are remnants of older volcanic edifices of Mt Pinatubo and hid it from views from distance. Pinatubo mostly noted for a failed geothermal development project. [Source: volcanodiscovery.com /*]

"Pinatubo is flanked to the west and probably underlain by by the Zambales Ophiolite Complex, an easterly-dipping section of Eocene oceanic crust which was uplifted in the late Oligocene. The second unit are sediments of the Tarlac Formation, mostly sandstone and siltstone in the older parts, and conglomerates and volcanic sediments and dikes in the younger. The Tarlac formation is found in the north, east and southeast of Pinatubo and formed contemporary with the oldest known volcanic centers in the area, including Mount Mataba or the diorite of the Dizon Mine, the sub-surface remnant of an ancient vent. The ancient volcanoes of the Tarlac Formation originated from the same east-dipping subduction along the Manila trench that continues to the present. /*\

"Ancient Pinatubo: Pinatubo was formed in 2 stages. The ancestral Pinatubo started to form about 1 million years ago, and built an andesite - dacite stratovolcano whose center was at the same location as today. Remnants of this precessor are seen in the ancient 3.5x4.5 wide caldera. Ancient Pinatubo had a number of flank vents, that formed the domes of Mount Negron, Mount Cuadrado, Mataba, Bituin plug, and the volcanic plug of Tapungho. Deep erosion in the Sacobia, Porac, Marimla, and Porac River valleys, and weathering of the lavas suggests that activity of the ancestral volcano ended several tens of thousands of years (or more) before the caldera-forming eruption and initial growth of the modern Pinatubo (ca. 35,000 years ago). /*\

"Modern Pinataubo: After the 1991 eruption, scientists (mainly from PHILVOLCS & USGS) carried out intensive fieldwork on the deposits of present-day Pinatubo to analyze its eruptive history. They distinguished at least 6 eruptive periods of modern Pinatubo, characterized by repeated, large explosive eruptions." /*\

See Separate Articles: Hiking on Pinatubo See CENTRAL LUZON factsanddetails.com; VOLCANOES IN THE PHILIPPINES factsanddetails.com ; PINATUBO VOLCANO AND ITS HUGE 1991 ERUPTION factsanddetails.com VOLCANO COMPONENTS, STRUCTURE AND ACTIVITY factsanddetails.com ; TYPES OF VOLCANOES factsanddetails.com ; VOLCANIC ERUPTIONS: TYPES, PHASES AND CAUSES factsanddetails.com ; DESTRUCTIVE ERUPTIONS: LAHARS, PYROCLASTIC FLOWS AND GLACIAL BURSTS factsanddetails.com

Websites and Sources on Volcanoes: USGS Volcanoes volcanoes.usgs.gov ; Volcano World volcano.oregonstate.edu ; Volcanoes.com volcanoes.com ; Wikipedia Volcano article Wikipedia , Smithsonian Global Volcanism Program volcano.si.edu operated by the Smithsonian has descriptions of volcanoes around the globe and a catalog of over 8,000 eruptions in the last 10,000 years.

Past Eruptions of Mount Pinatubo

1) Inararo Eruptive Period - more than 35,000 14C yr B.P. The largest eruption in the history of modern Pinatubo occurred 35,000 (radiocarbon) years ago. It deposited up to 100 m or more of pumice and ash flows on all sides of Mount Pinatubo. 2) Sacobia Eruptive Period - ~17,000 yr B.P. A phase of explosive eruptions occurred 17,000 years ago and produced 2 debris flow deposits which are visible on the north bank of the Sacobia River.

3) Pasbul Eruptive Period - ~9,000 yr B.P. A large explosive eruption occurred ca. 9000 years ago. It produced pyroclastic-flow and tephra-fall layers exposed along the road between Sitio Pasbul, Camias, Porac, and the Gumain River. The pyroclastic flows overtopped the southeastern rim of the Tayawan caldera and nearly or completely filled the valley of the Gumain River.

4) Crow Valley Eruptive Period - ~6,000-5,000 yr B.P. Large eruptions 6,000-5,000 years ago produced pyroclastic flow deposits on both sides of upper Crow valley. 5) Maraunot Eruptive Period - ~3,900(?)-2,300 yr B.P. Eruptions in this period produced pyroclastic flows and lahars. 6) Buag Eruptive Period - ca. 1450 A.D. The last activity cycle prior to the 1991 eruption was in 1450 ± 50 AD. It produced pyroclastic flows that entered all valley of Pinatubo except the Gumain and Porac rivers.

Massive Eruption of Pinatubo in 1991

The blast was strong enough knock off the top 250 meters of 1,745-meter-high, 5,770-foot-high Mt Pinatubo and make the daytime in the Philippines seem like night. One villager said it was like "a stampede of 100,000 animals." The National Geographic journalist Noel Grove described it as "a monstrous cannon, firing a shot with effects felt around the world."

No one had any idea that Pinatubo was going to erupt with such ferocity. It had been dormant for between 460 to 500 years and the only sign that something was going to happen was gas that started leaking out of the mountain two weeks before.

Ten billion cubic meters-roughly two cubic miles-of ash, rock and debris was hurled into the atmosphere from Pinatubu in a three day period. This is enough material to bury the District of Columbia to a level of 150 feet. Fist-size rocks and debris rained down for weeks. The layer of ash that was deposited was described as a giant sand trap.

In Manila, ash fell that was said to be like powdered beige snow. To keep the stuff out of their eyes, pedestrians walked the streets with plastic bags stretched over their heads. But ash was not the only problem in Manila the day the volcano erupted. Around 7:00pm earthquakes hit. The exit of the lava from the mountain had left a subterranean cavern that began falling in on itself, causing shocks. In Manila, light fixtures swayed overhead and, according to Grove, "chairs felt as uncertain as liquid."

Pinatubo Sulfuric Acid Cloud

The layer of sulfate aerosol scattered light sunlight and absorbed heat from the earth, cooling the planet's surface. Pinatubo caused world temperature to drop about a half a degree. Scientists, measuring the depth of the cloud by satellite observation, calculate that 2 percent of the incoming sunlight was deflected from the earth by the layer of sulfate aerosol.

Damage By Pinatubo

Families within 15 miles of the crater said that rocks as big as grapefruits came hurling down from the sky and mud flowed into the houses. Piercing the darkness was strange-colored lightning-blue, green and even red. All told 42,000 houses were destroyed, 1000 acres of cropland buried under ash, billions of dollars in economic losses and nearly 1,000 dead. American geologists, who had arrived several months, had warned the populace that a catastrophic was going to occur or it could have been a lot worse.

Pinatubo ash Most of dead were crushed by roofs that collapsed under the weight of ash or were swept away by landslides or lahars. Carlos H. Conde wrote in the International Herald Tribune, "The spectacular eruption of the Pinatubo volcano in 1991 initially caused few casualties, thanks to the timely evacuation of almost everyone living within 30 kilometers, or about 20 miles, of the volcano. But on June 15, when the eruption reached its climax, Typhoon Yunya swept in from the Pacific, washing millions of tons of tephra-airborne ash-out of the sky. Of the 300 people killed by the initial eruption, most died when their roofs collapsed under the weight of the deposits, which fell like snow but congealed into something like concrete. Communities near Pinatubo are still suffering. Each year, heavy rains cause new flows of volcanic debris in the surrounding valleys, ruining cropland and displacing villages. [Source: Carlos H. Conde, International Herald Tribune, December 12, 2006/]

Situated in central Luzon about 50 miles north of Manila, Clark Field sustained major damage when Mount Pinatubo erupted in 1991. The bases was decimated further when the U.S, Air Force pulled out after the eruption and looters ransacked the buildings. Clark is being transformed into a major international airport. It has two-mile-long runways that were made unusable by the ash from eruption that gets sucked into the engines during reverse thrusts and causes the ash to clog and freeze up the engines.

Worries About Volcanic Lake at Pinatubo

In August and September 2001, scientists became worried that a rain-swollen lake crater lake at Pinatubo might break through the crater walls and cause a catastrophic flood that might inundate villages and towns, killing lots of people and causing a lot of damage.

Some 25 million cubic meters of water was in the lake. With great fanfare engineers dug a ditch to drain water slowly from the lake and 40,000 people below the lake were evacuated. The water dribble down the ditch in a benign, dirty, brown stream that made many people wonder what all the fuss was about.

In 2004, the water in the lake suddenly turned a very dark brown and scientists tourists not drink it or swim in it. Ash from Pinatubo is now sold that is used in making building materials. Pumice stones are used in cosmetics, carpentry and washing stone washed jeans.

Lahars at Pinatubo

Lahars ravaged the Pinatubo for years after the volcano erupted. Each year during the rainy season, new lahars were created that slid down slopes at speeds up to 25mph and clogged up rivers, swamped rice fields and smothered towns and villages up to 35 miles away from the volcano. Scientists believe the lahars could keep being produced well into the 21st century.

The lasting effects of the lahars is much worse than the damage caused by Mount St. Helens. During the dry season, the landscape is barren and dusty and vehicles kick up huge clouds of debris when they pass by. In the rainy season the landscape turns to muck and vehicles have to make a seven hour detour. Eight rivers have been chocked by lahars, which means the water collects in large pools of stagnant green and smelly water.

The rain also causes river filled with volcanic silt to overflow their banks and flood fields and settlements with a gooey slurry of volcanic mud and water. When the volcanic material dries it forms a material as hard as concrete that have turned once productive rice fields into vast grey deserts.

One village and all of its rice fields were swallowed up by a gooey, sticky lahar right before the harvest season was to begin. In some places around Pinatubo, the layer of volcanic ejecta, sand and peddles and boulders is 30 meters (90 feet) thick.

Damage by Pinatubo Lahars

As of 1997, 9 billion cubic meters of lahar covered the area around Pinatubo, more than a 1,000 people had been killed and 1.2 million people (10 percent of the region's population) were left homeless as a result of lahars. In 1995, alone, more than 100,000 people were forced to evacuate their homes as a result of lahars. Hundred of millions of dollars have been lost in lost crops.

Many people displaced by the lahars live around Dapdap (60 miles from Manila), where people live in homes and along streets made from the volcanic material that destroyed their homes. Many people have lost their homes and fields. As of the late 1990s few people had jobs and many made money from begging. When they went outside they wrapped themselves like bedouins for protection from volcanic dust and grit kicked up by the winds.

The government built dikes and dams to contain the lahars, but in 1995 many of these structures were swept away by volcanic mud. In places were the dikes worked, often lahars that were directed away from one community were simply directed towards another.

One scientist told the New York Times, "During the rainy season, residents of rival villages invoke the names of their patron saints to save them from the lahar flows. It is a competition to see whose saints are more powerful with God. This has been replaced by the more mundane struggle of committees who can pull strings and reshape the engineering projects."

Aeta and Mt. Pinatubo

Many Aeta-a Negrito tribe- live or lived around Mt. Pinatubo, the volcano that erupted violently in 1991. Traditionally, the Aeta sacrificed a pig with a bottle of gin into the volcano's crater to placate Apo Malyari, the mountain god of Mt, Pinatubo and keep who live and work around the volcano safe. Apo Malyari is regarded as a combination of smoke, fire and earthquakes. According to legend he was unjustly trapped by lava under Pinatubo and escapes ever 400 or 500 years with great eruption.

Hundreds of Aeta died during and after the eruption of Mt. Pinatubo. Some of them died in the eruption itself. Others starved from a lack a food. Some of those who resettled in evacuation camps died of measles and other lowland diseases for which they had no immunity. Most of those that remained or were left behind in the villages died. Many who chose to hide out in caves rather than evacuate also died. The survivors were mainly those who evacuated far enough to get out of harms way.

The way of life of Aeta was dramatically changed after the eruption. The villages where they used to live are under meters of ash; trees that provided shade from the hot sun are gone; and their hunting grounds were closed. Many moved back to the mountain and grew what crops they could. The sandy soil made that difficult. Mountain rice turned yellow and withered when planted in the ash. Banana trees were about the only food sources that did well. But the Aeta complained they couldn't live on bananas alone.

Many Aeta remained in evacuation centers that looked like refugee camps. In the 1990s they wore Western cloths, worked as laborers, collected banana blossoms and bartered the for rice, and attended classes that aimed to teach them how to make handicrafts.

See Separate Article NEGRITOS AND TASADAY factsanddetails.com

Image Sources:

Text Sources: New York Times, Washington Post, Los Angeles Times, Times of London, Lonely Planet Guides, Library of Congress, Philippines Department of Tourism, Compton's Encyclopedia, The Guardian, National Geographic, Smithsonian magazine, The New Yorker, Time, Newsweek, Reuters, AP, AFP, Wall Street Journal, The Atlantic Monthly, The Economist, Foreign Policy, Wikipedia, BBC, CNN, and various books, websites and other publications.

Last updated April 2022

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PINATUBO VOLCANO AND ITS HUGE 1991 ERUPTION

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According to volcanodiscovery.com: "Prior to the eruption, Pinatubo was a little known volcano. There were no known historic eruptions. Before the eruption in 1991 Pinatubo was 1745 meters high (about 250 meters more than now), and was only 200 meters higher than the nearby peaks, which are remnants of older volcanic edifices of Mt Pinatubo and hid it from views from distance.

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https://docs.google.com/document/d/1GWeUGNDVWokIoZnyDc6kpEJ9T1T4xN_3cbv2zoG1Szo/edit

Ethan

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If you'd been on the Philippines island of Luzon on June 15, 1991, you'd have been forgiven for thinking that the world was ending.

Typhoon Yunya was screaming across the island, but the angry skies were nothing compared with the angry Earth. Mount Pinatubo, an unassuming volcano that no one had even realized was active until a few years prior, was blowing its top. A column of ash spewed 21 miles (34 kilometers) into the atmosphere, opening like an umbrella to form a cloud 249 miles (400 km) across.

On the way back down, Pinatubo's ash mixed with Yunya's rain, creating a concretelike mud that collapsed roofs more than 9 miles (15 km) away. The streets were choked with evacuees, including the scientists in charge of monitoring the volcano, who were reduced to rinsing their ash-streaked windshield with a six-pack of cherry soda.

The eruption of Mount Pinatubo was the second-largest volcanic cataclysm of the 20th century, second only to a 1912 eruption on the sparsely populated Alaskan Peninsula. Mount Pinatubo, on the other hand, threatened tens of thousands who lived on or near its slopes. [ In Photos: The Colossal Eruption of Mount Pinatubo]

Nonetheless, only a few hundred people died in the initial eruption, thanks to round-the-clock volcano monitoring, proactive evacuation plans, and a little bit of luck. It was a success that helped cement the importance of close volcano-watching - though scientists are still searching for the unique clues that might warn them that an eruption will be as large as Pinatubo's.
A giant awakens

(Image credit: USGS)

The first sign that Pinatubo might be restless came in mid-March 1991. Frequent earthquakes shook the area, alarming residents. On April 2, an explosion opened a line of steaming vents along the mountain.

The Philippine Institute of Volcanology and Seismology (PHIVOLCS) rushed to the scene, bearing five seismic monitors. They also called in the United States Geologic Survey's (USGS) Volcano Disaster Assistance Program, a group formed five years earlier to help with volcanic emergencies around the globe.

Pinatubo had not emitted so much as a volcanic burp in living memory, but a look at the area's geology revealed that the mountain could produce very large eruptions, said USGS team leader Chris Newhall, now the volcano group leader at the Earth Observatory of Singapore.

"But we didn't know whether it WOULD erupt, or whether an eruption would be LARGE," Newhall wrote in an email to LiveScience. "So you can't recommend an evacuation right away."

Instead, the team gathered every bit of information they could about the mountain. They deployed additional seismometers, walked around looking at ancient volcanic deposits and flew helicopter missions close to the volcano to see what was going on.

"We're kind of coming into a volcano that no one knew much about," said John Ewert, now the scientist-in-charge at the USGS Cascades Volcano Observatory. "There had been no monitoring, no baseline has been collected. No geologic map, no hazards map, nothing. ... There was an element of building the boat and rowing it at the same time."
Buildup to a blowout
On top of the scientific challenge, there was also a massive amount of personal pressure. About 500,000 people lived near Pinatubo, and convincing them that this unassuming, jungle-covered lump was a threat was no small feat. In addition, Clark Airbase, the U.S. facility that became the scientists' command center and home away from home, sat about 9 miles (15 km) from Pinatubo, and a base evacuation was not to be taken lightly.

In other words, if the scientists were going to urge an evacuation, the volcano had darn well better blow. [ 10 Biggest Volcanic Eruptions in History]

As May turned into June, the volcano continued rumbling and emitting streams of ash. By the morning of June 8, a lava dome appeared on the peak. This was a sign that hot magma was pushing up against the surface, stretching and bulging the land above. By June 9, officials had ordered 25,000 people out of the area. On June 10, American officials made the call to evacuate more than 14,000 service members and their families from Clark Airbase.

The suddenly empty airbase was just one more source of pressure for the scientists, who took the opportunity to move their base of operations to the side of the base farthest from the steaming volcano. USGS volcanologist Richard Hoblitt, now at Cascades Volcano Observatory, described the anxiety wryly.

"If the volcano had not performed, it wouldn't have been very good for our careers, let's put it that way," Hoblitt told LiveScience.
Ka-boom
They wouldn't have to wait long. At 8:51 a.m. local time on June 12, the seismometers on the mountain's slopes went haywire as the volcano sent a column of ash and steam 11 miles (19 km) into the air at the speed of an F-15 jet.

(Image credit: USGS)

As Hoblitt and Ewert watched the volcano blow, they felt relief. Their admonitions - and the evacuation of more than 60,000 people - had not been in vain. But the relief was followed by concern, as after the initial 40-minute eruption, Pinatubo started rumbling again. The volcano was just getting warmed up.

Over the next three days, the volcano spit out three more vertical eruptions and 13 smaller eruptions that produced pyroclastic flows(molten mixtures of ash, gas and rock that can sweep over the landscape at more than 60 miles (100 km) per hour).

And then, on June 15, Pinatubo really let loose. Sometime around 1:42 p.m., the stop-and-go eruptions turned into one long, roaring explosion. Chunks of pumice the size of golf balls fell at Clark Airbase. Ash spewed higher than it ever had before, and lahars, or mudflows, rushed down the slopes in a clatter of banging boulders.

With all of their seismometers swallowed by the volcano's pyroclastic flows, Hoblitt, Ewert and their colleagues evacuated Clark Airbase as Typhoon Yunya dumped rain overhead. Rain-soaked ash streaked their truck's windshield, Hoblitt said, so the scientists wiped it clean with cherry soda, the only beverage left in the airbase commissary that no one wanted to drink. They rode out the night 24 miles (38 km) away at an agricultural college, feeling the earth quake as Pinatubo's summit collapsed into a 1.5-mile (2.5 km) caldera.
The Aftermath
By the time Pinatubo's climactic eruption ended, a snowlike blanket of ash at least a half-inch (1 centimeter) thick coated 4,660 square miles (7,500 square km) of the island of Luzon. Over the next year, the ash spewed into the atmosphere by Pinatubo would lower global temperatures by an average of 0.9 degrees Fahrenheit (0.5 degrees Celsius). The volcano would continue smoldering and smoking for months. And for years afterward, monsoon season would wash ash down the mountain's slopes in devastating lahars, raising the initial death toll of the eruption from 200 or 300 to more than 700.

(Image credit: Willie Scott / USGS)

But for as large as Pinatubo's eruption was, the death toll was remarkably small. At least 20,000 lives were saved. Aggressive monitoring and public information campaigns did their job, PHIVOLCS director Raymundo S. Punongbayan wrote in " Fire and Mud," a USGS collection of papers about Pinatubo's eruption.

But a big part of the Pinatubo evacuation's success is owed to the volcano's timing, Hoblitt said.

"The fact is that the pace of the activity was just about right for people to react to it," he said. "There was a steady escalation and that escalated up and culminated in an eruption."

Many eruptions are much more strung out, he said, which makes people impatient and unlikely to listen to warnings that the big one is coming.

Pinatubo is not expected to erupt again for hundreds of years, assuming it keeps to its usual schedule. But if the mountain did blow today, Ewert said, monitoring it would be slightly easier, thanks to 20 years of technological advances. Today, the Internet makes it easier to consult with far-off scientists, he said, and GPS and radar satellites make it possible to measure changes in the ground caused by moving magma.

But despite the new tools, Hoblitt said, it's still difficult to predict exactly when a volcano will blow and how large its eruption will be.

"This is still not a 'turn the crank and solve the problem' skill," Hoblitt said. "There's a lot of experience and art that goes into dealing with restless volcanoes."

You can follow LiveScience senior writer Stephanie Pappas on Twitter . Follow LiveScience for the latest in science news and discoveries on Twitter @livescience and on .

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Pinatubo: Why the Biggest Volcanic Eruption Wasn't the Deadliest

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Twenty years ago, Mount Pinatubo in the Philippines blew its top in the largest volcanic eruption in living memory.