Archive for the 'Volcanoes' Category

Today in History: Krakatoa Volcano

August 27th, 2014 -- Posted in Volcanoes | No Comments »

On August 27, 1883 the Krakatoa island volcano erupted in Indonesia’s Sunda Strait. The scale of the volcanic eruption and resulting tsunami was cataclysmic. More than 36,000 lives were lost.

For more information click here for 19th Century History and here for an Australian Bureau of Meteorology article.

Worst Geologic Disasters of 2012

January 29th, 2013 -- Posted in Earthquakes, Natural Disasters, Volcanoes | No Comments »

guest post by Rebecca Shields

On April 11, two consecutive earthquakes with magnitudes of 8.2 and 8.6 occurred off the west coast of northern Sumatra, where the Sunda plate meets the Indi/Australian plate. Many earthquakes happen at these ‚Äėplate boundaries‚Äô due to movement of the plates themselves. This specific plate boundary is in the same location of the record 9.1 earthquake from December 26, 2004 that caused multiple tsunamis, killing over 230,000 people. Tsunamis occur when an earthquake creates a shift in a huge amount of landmass under the ocean. When this large amount of land moves under the water, an upswelling occurs, creating the tsunami wave. A tsunami did result from the April earthquakes, but people living in the surrounding areas were prepared and no one was hurt. Unlike recent years, no tsunami was able to cause enough destruction to be considered a disaster!

Like earthquakes, most volcanoes are located near plate boundaries. The volcano that affected the most people in 2012 is Volcan de Fuego. It is located in Guatemala on the ‚ÄėRing of Fire‚Äô. The Ring of Fire surrounds the Pacific Ocean and is made up of volcanoes. A few different plate boundaries come into play along the ring, but the result is the same: hundreds of volcanoes. When Volcan de Fuego erupted on September 13, 2012, the Guatemalan government called for the evacuation of almost 35,000 residents in 17 surrounding areas. Other significant eruptions of 2012 were the Plosky Tolbachik in Russia, Puyehue in Chile, and Etna in Italy.

Worst Geologic Disasters of 2012

Japan is a series of islands formed by volcanoes located on the Ring of Fire. Along with a healthy dose of volcanic activity, Japan experienced massive floods and landslides in 2012. In early July 2012, southern Japan experienced torrential rainfall exceeding 3.5in per hour, resulting in flash floods and at least 518 landslides across the country. Twenty-eight people were confirmed dead and over 250,000 people were ordered to evacuate. Landslides can be especially deadly due to the speed at which they can travel, sometimes up to 35 mph. They are made up of anything that gets in the way, creating an almost solid wall of debris. Landslides are oftentimes associated with floods because they are caused by the buildup of large amounts of water on a mountain slope or hillside.

All the geologic hazards discussed happen daily around the world. However, under the right conditions, they turn deadly very fast. It is always important to know what hazards are common in your area, and be prepared for all possibilities.

Volcano Erupts in Chile

June 5th, 2011 -- Posted in Volcanoes | No Comments »

by Victoria M. Johnson

The eruption of the Puyehue-Cordon-Caulle volcano chain has prompted the mass evacuation of thousands of residents in southern Chile. Located about 500 miles south of the capital, Santiago, the eruption has spewed volumes of smoke and ash. So far no lava flows have been observed.

Chile Volcano Eruption

As the strong smell of sulfur filled the air, officials said the volcano was spitting molten rock. Witnesses reported experiencing more than 20 earthquakes. No injuries have been reported.

“The Cordon Caulle (volcanic range) has entered an eruptive process, with an explosion resulting in a 10-kilometer-high gas column,” Chilean state emergency office ONEMI said. According to MSNBC, it was not immediately clear which of the chain’s four volcanoes had erupted because of ash cover and weather conditions.

The chain last saw a major eruption in 1960. Chile’s chain of about 2,000 volcanoes is the world’s second largest after Indonesia. Some 50 to 60 are on record as having erupted. Chile’s Chaiten volcano erupted in 2008 for the first time in thousands of years. Chile’s Llaima volcano, one of South America’s most active, erupted in 2008 and 2009.

Make Your Own Volcano

January 31st, 2011 -- Posted in Volcanoes | No Comments »

Whether for a science fair or for an earth science class, the school project all kids look forward to is to make their own volcano. I remember having a tall stratovolcano in mind, and being horribly embarrassed by my flat-as-a-pancake shield volcano. My volcano was all the more wretched by the fact that red molten lava didn’t spew out of it like some of the other kid’s projects did.

Kids With Their Volcano

But what an exciting time that was at school. I learned about the different kinds of volcanoes, how volcanoes are created, what our planet is like inside, and the effects of volcanic eruptions. Kids even talked about volcanoes at recess. That didn’t happen at any other time of the year. I’ve included some links for you to help your child with their important science project, lest they end up like me. Click here for steps to learn how to make your own volcano. Click here to see how to make your volcano erupt.

The Day the World Ended

January 22nd, 2011 -- Posted in Earthquakes, Natural Disasters, Volcanoes | No Comments »

If you‚Äôre at all like me, you enjoy watching disaster films. Asteroid collisions, volcanic eruptions, mega earthquakes, are all events I love to see (fictionalized‚ÄĒnot the real thing). Today the Syfy Channel has a disaster film marathon. With movies like NYC Tornado Terror, Category 6: Day of Destruction, Megafault, and Volcano: Nature Unleashed, scientists and regular citizens scramble to prevent the ultimate disaster that will end the world. In these films earthquakes, volcanic eruptions, or extreme weather systems threaten the world as we know it.

Earthquake Fault

I examined what it is I love so much about these kinds of movies and here‚Äôs what I discovered. There are people out there who dedicate their lives to studying our planet‚ÄĒdisaster films give them the recognition they deserve‚ÄĒas it is often their expertise that saves mankind. The threat of disaster or dealing with the aftermath of the disaster brings people together, giving a sense of hope for the future, that facing the worst the planet has in store for us, we will survive. I also like that sense of survival that comes out in these films, people have to use their wits to stay alive, they have to step up and be brave and do whatever it takes to live. Another thing I enjoy is the often thought-provoking question that many of these films ask. What about you? Share your thoughts on this topic.

The Worst Disasters of 2010

December 23rd, 2010 -- Posted in Earthquakes, Natural Disasters, Volcanoes | No Comments »

2010 has proved to be the deadliest year for natural disasters. This year alone, earthquakes, volcanoes, tsunamis, and landslides have killed a quarter of a million people.

Haiti Earthquake

It started on January 12, when Haiti’s devastating 7.0 magnitude earthquake killed more than 230,000 people and left more than 1 million people homeless. On February 27, a massive 8.8 magnitude earthquake struck Chile, killing more than 500 people. That quake also generated a tsunami that further incapacitated the region. March brought about the eruption of Iceland’s Eyjafjallajökull volcano. Melted ice from the glacier caused floods that led to the evacuation of 800 Icelanders, and volcanic ash forced the closure of air flights that stranded hundreds of thousands of travelers. On April 14, a 6.9 magnitude quake rocked Yushu, China, killing 3,000 people and injuring more than 12,0000. May 27 and 29 hit Guatemala hard. Pacaya volcano erupted first. Two days later a tropical storm caused destructive landslides. July brought devastating floods to Pakistan, killing about 2,000 people and affecting millions more. In August, China’s Gansu Province experienced massive mudslides that killed 1,500 people. And in October, Indonesia endured both a tsunami and the eruption of Mount Merapi volcano. Hundreds of thousands of people were evacuated and 350 people were killed. As we reflect on the enormous loss of life, we can only hope that Mother Nature is kinder to us in 2011.

Mount St. Helens 30 Years Ago

May 18th, 2010 -- Posted in Volcanoes | No Comments »

Mount St. Helens eruption

May 18, 1980 was a day we will all never forget. Who expected the beautiful mountain, where thousands hiked and camped each year, could unleash such deadly force? The Weather Channel commemorates the catastrophic eruption in an anniversary slideshow.

In case you don’t remember the powerful forces released that day, here’s some numbers to think about. A magnitude 5.1 earthquake preceded the collapse of the mountain peak. Pyroclastic  flows wiped out everything in it’s path including 250 miles of forest land and raised Spirit Lake’s water level by 200 feet. 520 million tons of ash swept across the country. 57 people died and over 200 homes were destroyed in the worst volcanic disaster in the United States.

The USGS had been monitoring Mount St. Helens for months. USGS volcanologist David Johnston reported the eruption, but he was one of those who lost their life that day. Still, scientists learned much from the eruption, from data they had never collected before, from a volcano they had been studying prior to the eruption, and a volcano they continue to study today.

Wall Street Journal Charts Largest Volcano Eruptions

May 8th, 2010 -- Posted in Volcanoes | No Comments »

Pelee Volcano

Last month the Wall Street Journal produced an interactive graphic to show the major volcanic eruptions within the past 200 years. I noticed a major volcanic eruption missing from the cool timeline and I was ready to call the Wall Street Journal to report their mistake. Surely Mount Pelée’s eruption in 1902 was omitted in error. That eruption on the pristine Caribbean island of Martinique killed more than 30,000 people. Pyroclystic flows, volcanic gases, and ash from the stratovolcano completely destroyed the town of Saint-Pierre, the largest city of Martinique.

Before I picked up my phone I referred to my notes, and the USGS web site, of course. And sure enough Mount Pelée’s eruption, even though it is considered the worst volcanic disaster of the 20th century, only has a VEI of 4. How could that be? The USGS themselves say the Mount Pelée eruption was very small, producing only about 3 percent of the volume of ash ejected during the May 1980 eruption of Mount St. Helens.

With the VEI measuring only Magnitude (measures the amount of lava produced), and Intensity (measures how fast the lava is produced), some of the most destructive eruptions have not been “very large.” It’s no wonder that some scientists are arguing for a change in the VEI to add other measurements such as levels of destruction and loss of life.

Iceland Volcano Causing Earthquakes

May 7th, 2010 -- Posted in Earthquakes, Volcanoes | No Comments »

Ash plume from Eyjafjallajökull

Updates from the Institute of Earth Sciences at the University of Icelandreport that at least 10 earthquakes have been located at Eyjafjallaj√∂kull¬†since midnight. Most are less that magnitude 2. Measurements show continued horizontal displacement around Eyjafjallaj√∂kull volcano. Explosive activity has increased, and with considerable tephra fallout, the cinder cone continues to build. Dark ash plumes have been observed at hieight of 20,000 ‚Äď 22,000 feet. Scientists have reported, ‚Äúeverything turned black‚ÄĚ. The lava channels are about 30 ‚Äď 60 m wide. And according to UPI, Iceland’s volcano roared back to life on Thursday. “The eruption has changed back to an explosive eruption, lava has stopped flowing and most of the magma gets scattered due to explosions in the crater,” the Icelandic Meteorological Office said.

Will more disruptions in air travel occur? Will Eyjafjallaj√∂kull volcano return to the eruptive intensity it displayed in April? Scientists continue to say that ‚Äúthere are no signs the eruption is about to end.‚ÄĚ

Top 10 Facts to Know About Stratovolcanoes

April 30th, 2010 -- Posted in Volcanoes | 20 Comments »

Mount Fuji, a stratovolcano

Of the four types of volcanoes, let’s take a close look at the dramatic stratovolcano.

1. Frequent pyroclastic eruptions give stratovolcanoes their towering cone shape.

2. Eruptions can originate from the summit or flank vents.

3. Subduction-zone stratovolcanoes, like Mount St. Helens, typically erupt with explosive force.

4. Some of the most powerful and destructive volcanoes in human history have been stratovolcanoes.

5. Stratovolcanoes are the most common type of volcano.

6. Of Earth’s 1,511 volcanoes known to have erupted in the past 10,000 years, 699 are stratovolcanoes.

7. Some of the most beautiful mountains in the world are stratovolcanoes, including Mount Rainer in Washington, Mount Fuji in Japan, and Kamchatka in Russia.

8. Magma, from deep in the Earth’s crust, travels through a conduit within the stratovolcano, which becomes lava when it erupts.

9. Between eruptions stratovolcanoes can be quiet for tens of thousands of years, seeming extinct.

10. Many cataclysmic eruptions throughout history were stratovolcanoes, including Mount Pelee in Martinique, El Chichon in Mexico, Mount Vesuvius in Italy, and Krakatoa in Indonesia, causing catastrophic loss of life.

Iceland Volcano Continues to Spew Lava

April 29th, 2010 -- Posted in Volcanoes | No Comments »


Eyjafjallajökull is one of the largest volcanoes in Iceland. Only three eruptions are known at Eyjafjallajökull in historical times, one in 920 A.D., another in 1612 AD, and the most recent in 1821. But on March 20, 2010 Eyjafjallajökull exploded back to life.

According to scientists at the Institute of Earth Sciences Nordic Volcanological Center, today the eruption in Eyjafjallajökull has a continuing discharge of meltwater from Gigjokull Glacier due to ice melt caused by the volcano. Booming sounds have been reported as far as 32 km from the eruption site. While ash and steam rise to an elevation of 3.6 km (12,000 ft), ejected lava reached heights of 660 feet.  Would we expect anything less from an active stratovolcano?

Scientists are monitoring Eyjafjallajökull with radar observations, GPS measurements, satellite images, seismic monitors, river gauges, aerial observations, and geologist’s inspections of tephra. Tephra is the term for materials of all types and sizes thrown into the air by a volcanic eruption.

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