How much ash was there from the May 18, 1980 eruption of Mount St. Helens?
During the 9 hours of vigorous eruptive activity on May 18, 1980, about 540 million tons of ash from Mount St. Helens fell over an area of more than 22,000 square miles (57,000 square kilometers). The total volume of the ash before its compaction by rainfall was about 0.3 cubic mile (1.3 cubic kilometers), equivalent to an area the size of a football field piled about 150 miles (240 kilometers) high with fluffy ash.
Learn more:
- Ash and Tephra Fall Hazards at Mount St. Helens
- Ash Cloud Simulations - What if Mount St. Helens produced an explosive eruption today?
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Why is it important to monitor volcanoes?
There are 161 potentially active volcanoes in the United States. According to a 2018 USGS assessment , 57 volcanoes are a high threat or very high threat to public safety. Many of these volcanoes have erupted in the recent past and will erupt again in the foreseeable future. As populations increase, areas near volcanoes are being developed and aviation routes are increasing. As a result, more...
Pre-1980 eruptive history of Mount St. Helens, Washington
Mount St. Helens erupts again: Activity from September 2004 through March 2005
Eruptions of Mount St. Helens : past, present, and future
Mount St. Helens - From the 1980 eruption to 2000
Volcanoes!
Volcanic-hazard zonation for Mount St. Helens, Washington, 1995
Road guide to volcanic deposits of Mount St. Helens and vicinity, Washington
The 1980 eruptions of Mount St. Helens, Washington
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- FAQ
Why is it important to monitor volcanoes?
There are 161 potentially active volcanoes in the United States. According to a 2018 USGS assessment , 57 volcanoes are a high threat or very high threat to public safety. Many of these volcanoes have erupted in the recent past and will erupt again in the foreseeable future. As populations increase, areas near volcanoes are being developed and aviation routes are increasing. As a result, more...
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Filter Total Items: 20
Pre-1980 eruptive history of Mount St. Helens, Washington
No abstract available.AuthorsMichael A. Clynne, David W. Ramsey, Edward W. Wolfe, James W. Hendley, Peter H. StaufferMount St. Helens erupts again: Activity from September 2004 through March 2005
Eruptive activity at Mount St. Helens captured the world’s attention in 1980 when the largest historical landslide on Earth and a powerful explosion reshaped the volcano, created its distinctive crater, and dramatically modified the surrounding landscape. Over the next 6 years, episodic extrusions of lava built a large dome in the crater. From 1987 to 2004, Mount St. Helens returned to a period ofAuthorsJon J. Major, William E. Scott, Carolyn Driedger, Dan DzurisinEruptions of Mount St. Helens : past, present, and future
No abstract available.AuthorsRobert I. Tilling, Lyn J. Topinka, Donald A. SwansonMount St. Helens - From the 1980 eruption to 2000
Mount St. Helens, Washington, is the most active volcano in the Cascade Range. Its most recent series of eruptions began in 1980 when a large landslide and powerful explosive eruption created a large crater, and ended 6 years later after more than a dozen extrusions of lava built a dome in the crater. Larger, longer lasting eruptions have occurred in the volcano's past and are likely to occur in tAuthorsSteve Brantley, Bobbie MyersVolcanoes!
Volcanoes is an interdisciplinary set of materials for grades 4-8. Through the story of the 1980 eruption of Mount St. Helens, students will answer fundamental questions about volcanoes: "What is a volcano?" "Where do volcanoes occur and why?" "What are the effects of volcanoes on the Earth system?" "What are the risks and the benefits of living near volcanoes?" "Can scientists forecast volcanic eAuthorsVolcanic-hazard zonation for Mount St. Helens, Washington, 1995
No abstract available.AuthorsE.W. Wolfe, T. C. PiersonRoad guide to volcanic deposits of Mount St. Helens and vicinity, Washington
Mount St. Helens, the most recently active and most intensively studied Cascades volcano, is in southwestern Washington. The volcano is a superb outdoor laboratory for studying volcanic processes, deposits of observed events, and deposits whose origins are inferred by classic geologic techniques, including analogy to recent deposits. During the past 4,500 years, Mount St. Helens has been more actiAuthorsMichael P. DoukasThe 1980 eruptions of Mount St. Helens, Washington
No abstract available.AuthorsPeter W. Lipman, Donal Ray Mullineaux - News