How much ash was there from the May 18, 1980 eruption of Mount St. Helens?

Knowledge about past eruptions of Yellowstone combined with mathematical models of volcanic ash dispersion help scientists determine where and how much ashfall will occur in possible future eruptions. During the three caldera-forming eruptions that occurred between 2.1 million and 640,000 years ago, tiny particles of volcanic ash covered much of the western half of North America. That ash was...

The May 18, 1980 eruptive column at Mount St. Helens fluctuated in height through the day, but the eruption subsided by late afternoon. By early May 19, the eruption had stopped. By that time, the ash cloud had spread to the central United States. Two days later, even though the ash cloud had become more diffuse, fine ash was detected by systems used to monitor air pollution in several cities of...

Kīlauea Volcano is renowned for its relatively benign eruptions of fluid lava flows. Therefore, many people were surprised by the small explosions that occurred in Halema`uma`u Crater in 2008 and 2018, and even more surprised to learn that volcanic ash was being erupted from a new gas vent. However, ash emissions from Halema`uma`u Crater are part of the volcano's legacy. Kīlauea's summit has...

Before May 18, 1980, Mount St. Helens ' summit altitude of 9,677 feet (2,950 meters) made it only the fifth highest peak in Washington State. It stood out handsomely, however, from surrounding hills because it rose thousands of feet above them and had a perennial cover of ice and snow. The peak rose more than 5,000 feet (1,524 meters) above its base, where the lower flanks merge with adjacent...

The eruptive history of Mount St. Helens began about 40,000 years ago with dacitic volcanism, which continued intermittently until about 2,500 years ago. This activity included numerous explosive eruptions over periods of hundreds to thousands of years, which were separated by apparent dormant intervals ranging in length from a few hundred to about 15,000 years. The range of rock types erupted by...

Some Native Americans of the Pacific Northwest variously called Mount St. Helens 'lawilátɬa ', or 'one from whom smoke comes'. The volcano lawilátɬa is listed (as Lawetlat’la) on the National Register of Historic Places and acknowledged as a Traditional Cultural Property of significance to the Cowlitz Indian Tribe and Confederated Tribes and Bands of the Yakama Nation. The modern name, Mount St...

Eruptions in the Cascades have occurred at an average rate of one to two per century during the last 4,000 years. Future eruptions are certain. Learn more: Eruptions in the Cascade Range During the Past 4,000 Years USGS Cascades Volcano Observatory

The world's largest eruption of the 20th century occurred in 1912 at Novarupta on the Alaska Peninsula in what is now Katmai National Park and Preserve. An estimated 15 cubic kilometers of magma was explosively erupted during 60 hours beginning on June 6th. This volume is equivalent to 230 years of eruption at Kilauea (Hawaii) or about 30 times the volume erupted by Mount St. Helens (Washington)...

The May 18, 1980 eruption of Mount St. Helens (Washington) was the most destructive in the history of the United States. Novarupta (Katmai) Volcano in Alaska erupted considerably more material in 1912, but owing to the isolation and sparse population of the region, there were no human deaths and little property damage. In contrast, the eruption of Mount St. Helens caused loss of lives and...

Yes. Encounters between aircraft and clouds of volcanic ash are a serious concern. Jet engines and other aircraft components are vulnerable to damage by fine, abrasive volcanic ash, which can drift in dangerous concentrations hundreds of miles downwind from an erupting volcano. In the past, many aircraft have accidentally encountered volcanic ash clouds, and in some cases jet engines have...

Yes, volcanoes can affect weather and the Earth's climate. Following the 1991 eruption of Mount Pinatubo in the Philippines, cooler than normal temperatures were recorded worldwide and brilliant sunsets and sunrises were attributed to this eruption that sent fine ash and gases high into the stratosphere, forming a large volcanic cloud that drifted around the world. The sulfur dioxide (SO2) in this...

Over geologic time, volcanic eruptions and related processes have directly and indirectly benefited mankind: Volcanic materials ultimately break down and weather to form some of the most fertile soils on Earth, cultivation of which has produced abundant food and fostered civilizations. The internal heat associated with young volcanic systems has been harnessed to produce geothermal energy . Most...