Why Mt. Lassen is what it is today
Lassen Peak, also known as Mount Lassen, is the southernmost active volcano in the Cascade Range. It is part of the Cascade Volcanic Arc which is an arc that covers southwestern British Columbia to northern California. Located in the Shasta Cascade region of Northern California, Lassen rises 2,000 meters above the surrounding terrain and has a volume of 0.5 cubic miles, making it one of the largest lava domes on Earth. It was created on the destroyed northeastern side of now gone Mount Tehama, a stratovolcano that was at least 1,000 feet higher than Lassen Peak.
Lassen Peak was named in honor of the Danish blacksmith Peter Lassen, who guided immigrants past this peak to the Sacramento Valley during the 1830s. His trail never found global long-term use because it was considered unsafe. This trail was replaced by the Nobles Emigrant Trail, named for the guide, William Nobles. In 1864, Helen Tanner Brodt became the first woman to reach the summit of Lassen Peak. A tarn lake on Lassen Peak was named "Lake Helen" in her honor.
In the 1914 to 1921 time zone, Lassen Peak emerged from inactivity with a series of steam explosions, dacite lava flows, and volcanic mud flows. There were 200 to 400 volcanic eruptions during this period of activity. Because of the eruptive activity and the area's brilliant volcanic beauty, Lassen Peak, Cinder Cone and the area surrounding were designated as the Lassen Volcanic National Park on August 9, 1916.
Mt. Lassen eruptions
On May 22, 1915, an explosive eruption at Lassen Peak devastated nearby areas and rained volcanic ash farther 200 miles to the east! This explosion was the most powerful in a series of eruptions from 1914 through 1917. ...
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...e than 30 volcanoes that have erupted over the past 300,000 years in the Lassen Peak volcanic area.
6. Lassen Peak has the highest known winter snowfall amounts in California. There is an average annual snowfall of 660 in, and in some years, more than 1,000 inches of snowfall at its base altitude of 8,250 feet at Lake Helen.
7. The Mount Lassen area receives more precipitation than anywhere in the Cascade Range south of the Three Sisters volcanoes in Oregon.
8. The heavy annual snowfall on Lassen Peak creates fourteen permanent patches of snow on and around the mountain top, despite Lassen's rather modest elevation, but no glaciers.
9. Lightning has been known to strike the summit of the volcano frequently during summer thunderstorms.
10. Lassen Peak and Mount St. Helens are the only two volcanoes in the contiguous United States to erupt during the 20th century.
In March 18, 1880 Mount St. Helens there was a catastrophic eruption that caused a huge volume of ash; the ash plume would be over central Colorado within 16 hours. After years of dedicated monitoring (knowing where to volcano is, unlike an earthquake not knowing exactly where this geological even is exactly) there was been increasing accuracy in forecasting eruptions.
Let’s begin with a little knowledge of Mt. Rainier and Yellowstone. Well, they are both in Washington. Rainier’s last few eruptions had lahars; we know this because of previous paths of destruction. This volcano is dormant, just blowing off a little steam sometimes. The last lahar was 500 years ago. If that happened again,
States on the lee, or down wind, sides of the great lakes receive lake-effect snow every year. For some cities this can push the average snowfall up to 400 inches. During the February storm of this year records were broken for the most snowfall in one storm. For a duration of the storm snow was falling at a rate of six inches or more per hour. Some of the images captured from the event leave some in disbelief that such a thing could even happen. Storms of this magnitude completely shut down all activity. Many areas do not have equipment capable of handling such mass amounts of snow, and even if they do the task is overwhelming. (weather.com 2006)
volcanoes that are located in our region. In our Big Bend and Fort Davis areas, when
Located in Northern California, Mount Shasta is a town of 3,394 people. The town sits at the base of the potentially active volcano that it got its name from, Mt.Shasta. At 14,179 feet the mountain supports seven glaciers that fuel countless springs throughout the area. The city is located along Interstate 5, just south of Weed, California and north of Dunsmuir, California.
The first time I saw Mt. Rainier for myself, was last summer when my boyfriend and I drove to Washington. It was the most beautiful, peaceful looking mountain I have ever seen. However, underneath it's great beauty, it hides a deadly secret. Mt. Rainier is one of the most dangerous volcanoes that we have here in the United States. One of the reasons it is so dangerous is because of it's great beauty. People enjoy looking at it, and the area that surrounds it, so they have made their homes here. Mt Rainier is not the only volcano I am interested in, in fact this last summer I also went to Mt. St. Helens and Crater Lake. But it is the volcano I chose to research for this paper because it does have so much beauty and at the same time so much power. I already know the basics about volcanoes, how they form, the different types, etc., but I wanted to find out more about what would happen if this great volcano were to erupt, what type of eruption would it be, and how would it affect the people that live around it.
The last eruption of this massive volcano occurred more than 115 years ago in 1884. The eruptions of Mount Rainier produce lahar mudflows which are similar to pyroclastic flows except they contain more water. These mudflows carry debris of volcanic ash and boulders that produce lava flows and have the consistency of concrete flowing down a mountain (C.M. Riley. Lahars can flow up to 100 kilometers per hour and can extend to more than 300 kilometers in distance. Because they are hard to predict, give off little warning signs, and move so rapidly through valleys, lahar slides are considered to be one of the most deadly volcanic hazards.
Maunaloa last erupted in 1938 and Kilauea has been erupting since January 3,1938. The Hawaii Volcanoes National Park was named a World Biosphere site by UNESCO in 1987. Kilauea is also called the world's only drive-in volcano.
Many of us know Mount Shasta to be a beautiful mountain and a popular tourist location in California. However, this mountain is much more than that, this mountain is actually a volcano. Volcanoes come with a number of hazards and a volcano of this size is of no exception. Previous eruptions on Mount Shasta have given us an idea of the power this volcano has and the damage it may do. With this information scientists are able to predict what may happen should another explosion occur.
The eruption on Mount Saint Helens has a specific cause and comes with many effects. A multifold of people would say that the “mountain looked like the site of an atomic blast” (Bredeson 30). That is a very accurate depiction as it took great power to inflict as much damage as it did. The reason for this impressive amount of force is that when magma is built up with pressure and an earthquake hits, the pressure gets magnified and the volcano explodes (Lewis). This is exactly what happened inside Mount Saint Helens. Furthermore, it has been revealed that “The earthquake that triggered the explosion was a 5.2 on the Richter scale” (Gunn 559). The earthquake to the magma can be compared as a match to gasoline. Even though the earthquake was not huge, the scale of the eruption was much greater than that of the earthquake (Gunn 560). The earthquake was only the trigger that allowed for more devastating things to occur. Thirteen hundred feet of the volcano were lost in the explosion followed by landslides, mudslides, and lava flows...
37,600 years ago with dacite and andesite eruptions of pumice and ash. Mudflows were very significant forces in all of St. Helens' eruptive cycles. Starting around 2500 BC eruptions of large amounts of ash and yellowish-brown pumice covered thousands of square miles. This eruptive cycle lasted until about 1600 BC. After 400 years of inactivity, St. Helens came alive again around 1200 BC. This cycle, which lasted until about 800 BC, is characterized by smaller volume eruptions.
Stories about volcanoes are captivating. Myths come in different versions, but all of them are capable of capturing yours, and everybody’s imagination.
From modern examples and records we know that volcanic activity can set of a chai...
The earliest outcropping volcanic deposits date back to about 25,000 years ago. The lavas observed at a -1125 m bore-hole are about 0,3-0,5 million years old. It is known for the first eruption of which an eyewitness account is preserved, in 79 AD. Geologically, Vesuvio is unique for its unusual versatility. Its activity ranging from Hawaiian-style release of liquid lava, fountaining and lava lakes, over Strombolian and Vulcanian activity to violently explosive, plinian events that produce pyroclastic flows and surges.