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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) in 1980!
Due to the remote location of the eruption, scientists did not visit the site until 1918, when they found the Ukak River valley filled with volcanic deposits and steaming fumaroles. They called it the "Valley of Ten Thousand Smokes."
Learn more: The Novarupta-Katmai eruption of 1912 - largest eruption of the twentieth century; centennial perspectives
There is no definitive evidence that an eruption at one volcano can trigger an eruption at a volcano that’s hundreds of kilometers/miles away or on a different continent. There are a few historic examples of simultaneous eruptions from volcanoes (or volcanic vents) located within about 10 kilometers (6 miles) of each other, but it's difficult to determine whether one eruption caused the other...
Volcanoes that have produced exceedingly voluminous pyroclastic eruptions and formed large calderas in the past 2 million years include Yellowstone in northwest Wyoming, Long Valley in eastern California, Toba in Indonesia, and Taupo in New Zealand. Other 'supervolcanoes' would likely include the large caldera volcanoes of Japan, Indonesia, Alaska (e.g. Aniakchak, Emmons, Fisher), and other areas...
The term "supervolcano" implies a volcanic center that has had an eruption of magnitude 8 on the Volcano Explosivity Index (VEI), meaning that at one point in time it erupted more than 1,000 cubic kilometers (240 cubic miles) of material. In the early 2000s, the term “supereruption” began being used as a catchy way to describe VEI 8 eruptions. Explosive events of this size erupt so much magma that...
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...
Most earthquakes and volcanic eruptions do not strike randomly but occur in specific areas, such as along plate boundaries. One such area is the circum-Pacific Ring of Fire, where the Pacific Plate meets many surrounding tectonic plates. The Ring of Fire is the most seismically and volcanically active zone in the world. Learn more: USGS Volcano Hazards Program
Rising gradually to more than 4 km (2.5 mi) above sea level, Hawaii’s Mauna Loa is the largest active volcano on our planet. Its submarine flanks descend to the sea floor an additional 5 km (3 mi), and the sea floor in turn is depressed by Mauna Loa's great mass another 8 km (5 mi). This makes the volcano's summit about 17 km (10.5 mi) above its base! Learn more: USGS Hawaiian Volcano Observatory
The United States has 169 active volcanoes. More than half of them could erupt explosively, sending ash up to 20,000 or 30,000 feet where commercial air traffic flies. USGS scientists are working to improve our understanding of volcano hazards to help protect communities and reduce the risks.
Video Sections:
The United States has 169 active volcanoes. More than half of them could erupt explosively, sending ash up to 20,000 or 30,000 feet where commercial air traffic flies. USGS scientists are working to improve our understanding of volcano hazards to help protect communities and reduce the risks.
Video Sections:
-- a Centennial perspective of the Novarupta-Katmai eruption, the largest of the 20th century
By Judy Fierstein, USGS
-- a Centennial perspective of the Novarupta-Katmai eruption, the largest of the 20th century
By Judy Fierstein, USGS
Debris flows are hazardous flows of rock, sediment and water that surge down mountain slopes and into adjacent valleys. Hydrologist Richard Iverson describes the nature of debris-flow research and explains how debris flow experiments are conducted at the USGS Debris Flow Flume, west of Eugene, Oregon.
Debris flows are hazardous flows of rock, sediment and water that surge down mountain slopes and into adjacent valleys. Hydrologist Richard Iverson describes the nature of debris-flow research and explains how debris flow experiments are conducted at the USGS Debris Flow Flume, west of Eugene, Oregon.
Volcanic ash is geographically the most widespread of all volcanic hazards. USGS geologist Larry Mastin describes how volcanic ash can disrupt lives many thousands of miles from an erupting volcano. The development of ash cloud models and ash cloud disruption to air traffic is highlighted.
Volcanic ash is geographically the most widespread of all volcanic hazards. USGS geologist Larry Mastin describes how volcanic ash can disrupt lives many thousands of miles from an erupting volcano. The development of ash cloud models and ash cloud disruption to air traffic is highlighted.
USGS technologist Rick LaHusen describes how the development and deployment of instruments plays a crucial role in mitigating volcanic hazards.
USGS technologist Rick LaHusen describes how the development and deployment of instruments plays a crucial role in mitigating volcanic hazards.
MODIS Aqua 1-km resolution true color satellite image shows a resuspended ash cloud generated from high winds scouring the dry, unvegetated deposits in the Valley of Ten Thousand Smokes. The cloud stretches across Shelikof Strait to western Kodiak Island.
MODIS Aqua 1-km resolution true color satellite image shows a resuspended ash cloud generated from high winds scouring the dry, unvegetated deposits in the Valley of Ten Thousand Smokes. The cloud stretches across Shelikof Strait to western Kodiak Island.
Schematic illustration showing the 1912 Novarupta eruption in Alaska and the caldera collapse at Mount Katmai, 10.6 km (about 6.6 miles) to the northeast.
Schematic illustration showing the 1912 Novarupta eruption in Alaska and the caldera collapse at Mount Katmai, 10.6 km (about 6.6 miles) to the northeast.
View southeast from Overlook Cabin looking over the Valley of Ten Thousand Smokes. The pyroclastic and ash deposits that fill the valley remain nearly vegetation-free more than 100 years after the 1912 Novarupta-Katmai eruption.
View southeast from Overlook Cabin looking over the Valley of Ten Thousand Smokes. The pyroclastic and ash deposits that fill the valley remain nearly vegetation-free more than 100 years after the 1912 Novarupta-Katmai eruption.
Novarupta Dome, with Falling Mountain and the upper valley portion of the Valley of Ten Thousand Smokes in the background. Photo by Tom Miller, June 1979.
Novarupta Dome, with Falling Mountain and the upper valley portion of the Valley of Ten Thousand Smokes in the background. Photo by Tom Miller, June 1979.
Valley of Ten Thousand Smokes in Katmai National Park, circa 1922. Windy Creek is in the foreground. Following the June 6, 1912 eruption of Novarupta-Katmai, thousands of fumaroles filled the valley for many years. Buried snow fields, glacial streams, and precipitation were converted to steam by the heat trapped in the pyroclastic flow.
Valley of Ten Thousand Smokes in Katmai National Park, circa 1922. Windy Creek is in the foreground. Following the June 6, 1912 eruption of Novarupta-Katmai, thousands of fumaroles filled the valley for many years. Buried snow fields, glacial streams, and precipitation were converted to steam by the heat trapped in the pyroclastic flow.
Volcanic ash drifts around houses at Katmai after the June 1912 eruption of Novarupta Volcano. Church in the distant background. August 13, 1912.
Volcanic ash drifts around houses at Katmai after the June 1912 eruption of Novarupta Volcano. Church in the distant background. August 13, 1912.
There is no definitive evidence that an eruption at one volcano can trigger an eruption at a volcano that’s hundreds of kilometers/miles away or on a different continent. There are a few historic examples of simultaneous eruptions from volcanoes (or volcanic vents) located within about 10 kilometers (6 miles) of each other, but it's difficult to determine whether one eruption caused the other...
Volcanoes that have produced exceedingly voluminous pyroclastic eruptions and formed large calderas in the past 2 million years include Yellowstone in northwest Wyoming, Long Valley in eastern California, Toba in Indonesia, and Taupo in New Zealand. Other 'supervolcanoes' would likely include the large caldera volcanoes of Japan, Indonesia, Alaska (e.g. Aniakchak, Emmons, Fisher), and other areas...
The term "supervolcano" implies a volcanic center that has had an eruption of magnitude 8 on the Volcano Explosivity Index (VEI), meaning that at one point in time it erupted more than 1,000 cubic kilometers (240 cubic miles) of material. In the early 2000s, the term “supereruption” began being used as a catchy way to describe VEI 8 eruptions. Explosive events of this size erupt so much magma that...
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...
Most earthquakes and volcanic eruptions do not strike randomly but occur in specific areas, such as along plate boundaries. One such area is the circum-Pacific Ring of Fire, where the Pacific Plate meets many surrounding tectonic plates. The Ring of Fire is the most seismically and volcanically active zone in the world. Learn more: USGS Volcano Hazards Program
Rising gradually to more than 4 km (2.5 mi) above sea level, Hawaii’s Mauna Loa is the largest active volcano on our planet. Its submarine flanks descend to the sea floor an additional 5 km (3 mi), and the sea floor in turn is depressed by Mauna Loa's great mass another 8 km (5 mi). This makes the volcano's summit about 17 km (10.5 mi) above its base! Learn more: USGS Hawaiian Volcano Observatory
The United States has 169 active volcanoes. More than half of them could erupt explosively, sending ash up to 20,000 or 30,000 feet where commercial air traffic flies. USGS scientists are working to improve our understanding of volcano hazards to help protect communities and reduce the risks.
Video Sections:
The United States has 169 active volcanoes. More than half of them could erupt explosively, sending ash up to 20,000 or 30,000 feet where commercial air traffic flies. USGS scientists are working to improve our understanding of volcano hazards to help protect communities and reduce the risks.
Video Sections:
-- a Centennial perspective of the Novarupta-Katmai eruption, the largest of the 20th century
By Judy Fierstein, USGS
-- a Centennial perspective of the Novarupta-Katmai eruption, the largest of the 20th century
By Judy Fierstein, USGS
Debris flows are hazardous flows of rock, sediment and water that surge down mountain slopes and into adjacent valleys. Hydrologist Richard Iverson describes the nature of debris-flow research and explains how debris flow experiments are conducted at the USGS Debris Flow Flume, west of Eugene, Oregon.
Debris flows are hazardous flows of rock, sediment and water that surge down mountain slopes and into adjacent valleys. Hydrologist Richard Iverson describes the nature of debris-flow research and explains how debris flow experiments are conducted at the USGS Debris Flow Flume, west of Eugene, Oregon.
Volcanic ash is geographically the most widespread of all volcanic hazards. USGS geologist Larry Mastin describes how volcanic ash can disrupt lives many thousands of miles from an erupting volcano. The development of ash cloud models and ash cloud disruption to air traffic is highlighted.
Volcanic ash is geographically the most widespread of all volcanic hazards. USGS geologist Larry Mastin describes how volcanic ash can disrupt lives many thousands of miles from an erupting volcano. The development of ash cloud models and ash cloud disruption to air traffic is highlighted.
USGS technologist Rick LaHusen describes how the development and deployment of instruments plays a crucial role in mitigating volcanic hazards.
USGS technologist Rick LaHusen describes how the development and deployment of instruments plays a crucial role in mitigating volcanic hazards.
MODIS Aqua 1-km resolution true color satellite image shows a resuspended ash cloud generated from high winds scouring the dry, unvegetated deposits in the Valley of Ten Thousand Smokes. The cloud stretches across Shelikof Strait to western Kodiak Island.
MODIS Aqua 1-km resolution true color satellite image shows a resuspended ash cloud generated from high winds scouring the dry, unvegetated deposits in the Valley of Ten Thousand Smokes. The cloud stretches across Shelikof Strait to western Kodiak Island.
Schematic illustration showing the 1912 Novarupta eruption in Alaska and the caldera collapse at Mount Katmai, 10.6 km (about 6.6 miles) to the northeast.
Schematic illustration showing the 1912 Novarupta eruption in Alaska and the caldera collapse at Mount Katmai, 10.6 km (about 6.6 miles) to the northeast.
View southeast from Overlook Cabin looking over the Valley of Ten Thousand Smokes. The pyroclastic and ash deposits that fill the valley remain nearly vegetation-free more than 100 years after the 1912 Novarupta-Katmai eruption.
View southeast from Overlook Cabin looking over the Valley of Ten Thousand Smokes. The pyroclastic and ash deposits that fill the valley remain nearly vegetation-free more than 100 years after the 1912 Novarupta-Katmai eruption.
Novarupta Dome, with Falling Mountain and the upper valley portion of the Valley of Ten Thousand Smokes in the background. Photo by Tom Miller, June 1979.
Novarupta Dome, with Falling Mountain and the upper valley portion of the Valley of Ten Thousand Smokes in the background. Photo by Tom Miller, June 1979.
Valley of Ten Thousand Smokes in Katmai National Park, circa 1922. Windy Creek is in the foreground. Following the June 6, 1912 eruption of Novarupta-Katmai, thousands of fumaroles filled the valley for many years. Buried snow fields, glacial streams, and precipitation were converted to steam by the heat trapped in the pyroclastic flow.
Valley of Ten Thousand Smokes in Katmai National Park, circa 1922. Windy Creek is in the foreground. Following the June 6, 1912 eruption of Novarupta-Katmai, thousands of fumaroles filled the valley for many years. Buried snow fields, glacial streams, and precipitation were converted to steam by the heat trapped in the pyroclastic flow.
Volcanic ash drifts around houses at Katmai after the June 1912 eruption of Novarupta Volcano. Church in the distant background. August 13, 1912.
Volcanic ash drifts around houses at Katmai after the June 1912 eruption of Novarupta Volcano. Church in the distant background. August 13, 1912.