Mount St. Helens is an active volcano located in the Cascade Range of southwestern Washington State, in the United States. It is one of the most famous volcanoes in the world, and the most well-known in the contiguous United States, for its tremendous 1980 eruption that was the deadliest and most economically destructive volcanic event in the history of the United States. Today, the volcano is monitored closely by the United States Geological Survey (USGS), on account of its ongoing activity.
A Brief History of Mount St. Helens
Mount St. Helens is part of the Cascade Volcanic Arc, a chain of volcanoes that stretches from northern California up to British Columbia in Canada. It is located in the Gifford Pinchot National Forest, and is one of five volcanoes in the arc that are considered active. It is the most recently active volcano in the arc, with its last major eruption occurring in 1980.
The volcano is named after the British naval officer and explorer, George Vancouver, who named the volcano after his friend, Alleyne Fitzherbert, the Baron St. Helens. The volcano has had several major eruptions over the past centuries, including at least four during the 19th century. The most famous of these was the 1980 eruption, which was the most destructive volcanic event in the history of the United States.
The 1980 Eruption of Mount St. Helens
On May 18, 1980, Mount St. Helens unleashed an explosive eruption that was heard hundreds of miles away. This eruption was one of the largest in the history of the United States, and was the most destructive in terms of its economic impact.
The eruption was caused by an earthquake measuring 5.1 on the Richter scale, which triggered a massive landslide that removed the entire north face of the volcano. This landslide then caused a lateral blast of hot gas and ash that traveled at speeds of up to 670 miles per hour. In the immediate aftermath of the eruption, 57 people were killed and more than 7,000 animals were killed.
The eruption also caused significant environmental damage, including the destruction of more than 230 square miles of forest and the contamination of nearby rivers and lakes with volcanic ash. In the aftermath of the eruption, the USGS established a monitoring program to measure the ongoing activity of the volcano.
Mount St. Helens Today
After the 1980 eruption, Mount St. Helens began to slowly rebuild itself through a process called dome growth. This process is characterized by the slow accumulation of lava and ash, which are then cemented together by the heat of the eruption. This process of dome growth has been ongoing since the 1980 eruption, with the volcano growing in height by an average of 13 feet per year.
Today, the volcano is around 8,365 feet in height, with its highest point being the lava dome at the summit. The lava dome is a raised cone-shaped feature, made up of lava and volcanic debris that has been pushed up by the volcano’s ongoing activity. The lava dome is the most visible feature of the volcano, and is estimated to be around 1,000 feet in height and 2,400 feet in width.
Monitoring Mount St. Helens
The USGS continues to monitor Mount St. Helens on a daily basis. The volcano is monitored for signs of activity, such as earthquakes, steam-and-ash plumes, and variations in ground deformation. This data is then used to assess the likelihood of an eruption and to issue warnings if necessary.
In addition to monitoring the volcano, the USGS also conducts research into the volcano and its ongoing activity. This research is used to better understand how the volcano works and to help better predict future eruptions.
Visiting Mount St. Helens
Mount St. Helens is a popular tourist destination, and visitors can take guided tours of the volcano and its surroundings. Tours typically include visits to the nearby Johnston Ridge Observatory, as well as hikes to the summit of the volcano, which offer stunning views of the surrounding landscape. Visitors can also take helicopter rides over the volcano, which provide an up-close look at its lava dome and ongoing activity.
Frequently Asked Questions
What is the height of Mount St. Helens?
The height of Mount St. Helens is 8,365 feet, with its highest point being the lava dome at the summit, which is estimated to be around 1,000 feet in height and 2,400 feet in width.
When was Mount St. Helens last active?
Mount St. Helens last erupted on May 18, 1980, with this eruption being the most destructive and economically damaging volcanic event in the history of the United States.
How is Mount St. Helens monitored?
Mount St. Helens is monitored on a daily basis by the United States Geological Survey (USGS). The volcano is monitored for signs of activity, such as earthquakes, steam-and-ash plumes, and variations in ground deformation.
What is the lava dome at Mount St. Helens?
The lava dome at Mount St. Helens is a raised cone-shaped feature, made up of lava and volcanic debris that has been pushed up by the volcano’s ongoing activity. The lava dome is the most visible feature of the volcano, and is estimated to be around 1,000 feet in height and 2,400 feet in width.
Can I visit Mount St. Helens?
Yes, Mount St. Helens is a popular tourist destination, and visitors can take guided tours of the volcano and its surroundings. Tours typically include visits to the nearby Johnston Ridge Observatory, as well as hikes to the summit of the volcano, which offer stunning views of the surrounding landscape. Visitors can also take helicopter rides over the volcano, which provide an up-close look at its lava dome and ongoing activity.
What kind of damage did the 1980 eruption of Mount St. Helens cause?
The 1980 eruption of Mount St. Helens caused significant damage, including the destruction of more than 230 square miles of forest and the contamination of nearby rivers and lakes with volcanic ash. In the aftermath of the eruption, 57 people were killed and more than 7,000 animals were killed.
What is the process of dome growth at Mount St. Helens?
The process of dome growth at Mount St. Helens is characterized by the slow accumulation of lava and ash, which are then cemented together by the heat of the eruption. This process of dome growth has been ongoing since the 1980 eruption, with the volcano growing in height by an average of 13 feet per year.
What is the Cascade Volcanic Arc?
The Cascade Volcanic Arc is a chain of volcanoes that stretches from northern California up to British Columbia in Canada. Mount St. Helens is part of this chain, and is one of five volcanoes in the arc that are considered active. It is the most recently active volcano in the arc, with its last major eruption occurring in 1980.
How did the 1980 eruption of Mount St. Helens occur?
The 1980 eruption of Mount St. Helens was caused by an earthquake measuring 5.1 on the Richter scale, which triggered a massive landslide that removed the entire north face of the volcano. This landslide then caused a lateral blast of hot gas and ash that traveled at speeds of up to 670 miles per hour.