A perspective view of Mount hood, made from the OR_Sandy_River_2007 lidar data
Which volcanoes in the contiguous United States have erupted since the Nation was founded?
Excluding steam eruptions, these volcanoes have shown activity:
- Mount St. Helens, Washington - Eruptions and/or lava dome growth occurred in the late 1700s, 1800-1857, 1980-1986, and 2004-2008.
- Lassen Peak, California - A series of steam blasts began on May 30, 1914. An eruption occurred 12 months later on May 21, 1915. Minor activity continued through the middle of 1917.
- Mount Hood, Oregon - After being dormant for over 1,000 years, Mount Hood had an eruptive period beginning in 1781 that lasted for about a decade. In the mid-1800s, local residents reported minor explosive activity.
Related
What was the largest volcanic eruption in the 20th century?
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)...
Will extinct volcanoes on the east coast of the U.S. erupt again?
No. The geologic forces that generated volcanoes in the eastern United States millions of years ago no longer exist. Through plate tectonics, the eastern U.S. has been isolated from the global tectonic features (tectonic plate boundaries and hot spots in the mantle), that cause volcanic activity. So new volcanic activity is not possible now or in the near future. If you wait around several hundred...
Which volcanic eruptions were the deadliest?
Deadliest Volcanic Eruptions Since 1500 A.D. Eruption Year Casualties Major Cause Nevado del Ruiz, Colombia 1985 25,000 1,3 Mudflows 3 Mont Pelée, Martinique 1902 30,000 1 (29,025) 2 Pyroclastic flows 2 Krakatau, Indonesia 1883 36,000 1 (36,417) 2 Tsunami 2 Tambora, Indonesia 1815 92,000 1,2 Starvation 2 Unzendake, Japan 1792 15,000 1 (14,030) 2 Volcano collapse, Tsunami 2 Lakagigar (Laki)...
How Do Volcanoes Erupt?
Deep within the Earth it is so hot that some rocks slowly melt and become a thick flowing substance called magma. Since it is lighter than the solid rock around it, magma rises and collects in magma chambers. Eventually, some of the magma pushes through vents and fissures to the Earth's surface. Magma that has erupted is called lava. Some volcanic eruptions are explosive and others are not. The...
How many active volcanoes are there on Earth?
There are about 1,350 potentially active volcanoes worldwide, aside from the continuous belts of volcanoes on the ocean floor at spreading centers like the Mid-Atlantic Ridge. About 500 of those 1,350 volcanoes have erupted in historical time. Many of those are located along the Pacific Rim in what is known as the " Ring of Fire." In the United States, volcanoes in the Cascade Range and Alaska...
What was the most destructive volcanic eruption in the history of the United States?
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...
Where does the United States rank in the number of volcanoes?
The United States ranks third, behind Indonesia and Japan, in the number of historically active volcanoes (that is, those for which we have written accounts of eruptions). In addition, about 10 percent of the more than 1,500 volcanoes that have erupted in the past 10,000 years are located in the United States. Most of these volcanoes are found in the Aleutian Islands, the Alaska Peninsula, the...
Where is the largest active volcano in the world?
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
Are there earthquakes associated with Mount Hood?
Mount Hood is one of the most seismically active volcanoes in the Washington and Oregon Cascades, and the most seismically active volcano in Oregon. In an average month 1-2 earthquakes are located within 5 km (3 miles) of the summit. Earthquakes large enough to be felt occur on Mount Hood every two years on average. Seismic monitoring, in effect since 1977, indicates a generalized concentration of...
When did Lassen Peak last erupt?
The most recent eruptive activity at Lassen Peak (California) took place in 1914-1917. This eruptive episode began on May 30, 1914, when a small phreatic eruption occurred at a new vent near the summit of the peak. More than 150 explosions of various sizes occurred during the following year. By mid-May 1915, the eruption changed in character; lava appeared in the summit crater and subsequently...
How would an eruption of Mount Rainier compare to the 1980 eruption of Mount St. Helens?
Eruptions of Mount Rainier usually produce much less volcanic ash than do eruptions at Mount St. Helens. However, owing to the volcano's great height and widespread cover of snow and glacier ice, eruption triggered debris flows ( lahars) at Mount Rainier are likely to be much larger--and will travel a greater distance--than those at Mount St. Helens in 1980. Furthermore, areas at risk from debris...
How many eruptions have there been in the Cascades during the last 4,000 years?
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
A perspective view of Mount hood
A perspective view of Mount hood, made from the OR_Sandy_River_2007 lidar data
USGS geologist viewing the northeastern slope of Mount Hood from Shellrock monitoring station.
PubTalk 04/2015—"Fearfully Grand" Eruptions: Lassen Peak, CA, 1914-17
Title: A Sight "Fearfully Grand" Eruptions of Lassen Peak, California, 1914 to1917
- A summary of the eruptions and their effects
- Illustrated with historical photographs
Title: A Sight "Fearfully Grand" Eruptions of Lassen Peak, California, 1914 to1917
- A summary of the eruptions and their effects
- Illustrated with historical photographs
Mount Hood dominates the skyline outside of Portland, Oregon
A major eruption of Mount Hood would pose a great hazard to the regional economy.
A major eruption of Mount Hood would pose a great hazard to the regional economy.
PubTalk 1/2012 — Lassen Volcanic National Park
--a wonderland of volcanoes and thermal features
By Patrick Muffler, Geologist Emeritus
--a wonderland of volcanoes and thermal features
By Patrick Muffler, Geologist Emeritus
Mount Hood, OR
View of Mount Hood from Pittock Mansion, Portland, OR.
View of Mount Hood from Pittock Mansion, Portland, OR.
Mount St. Helens: May 18, 1980
USGS scientists recount their experiences before, during and after the May 18, 1980 eruption of Mount St. Helens. Loss of their colleague David A. Johnston and 56 others in the eruption cast a pall over one of the most dramatic geologic moments in American history.
USGS scientists recount their experiences before, during and after the May 18, 1980 eruption of Mount St. Helens. Loss of their colleague David A. Johnston and 56 others in the eruption cast a pall over one of the most dramatic geologic moments in American history.
Mount St. Helens: A Catalyst for Change
The May 18, 1980 eruption of Mount St. Helens triggered a growth in volcano science and volcano monitoring. Five USGS volcano observatories have been established since the eruption. With new technologies and improved awareness of volcanic hazards USGS scientists are helping save lives and property across the planet.
The May 18, 1980 eruption of Mount St. Helens triggered a growth in volcano science and volcano monitoring. Five USGS volcano observatories have been established since the eruption. With new technologies and improved awareness of volcanic hazards USGS scientists are helping save lives and property across the planet.
Lassen Peak's Devastated Area photographed from the air in 1994.
Lassen Peak's Devastated Area photographed from the air in 1994.
Lassen Peak's Devastated Area photographed from the air in 1994.
Eruption of Mount St. Helens May 19, 1980
May 18, 1980 eruption of Mount St. Helens from southwest. Note the pyroclastic density currents spilling over the crater rim.
May 18, 1980 eruption of Mount St. Helens from southwest. Note the pyroclastic density currents spilling over the crater rim.
Mt. St. Helens before the eruption
Mt. St. Helens the day before the eruption, May 17, 1980.
Mt. St. Helens the day before the eruption, May 17, 1980.
Lava and mudflows from Lassen Peak, May 22, 1915
Benjamin F. Loomis Historical Photograph Collection: Lassen Peak showing new lava flow on summit and large mudflows on slopes. Photo courtesy of NPS.
Benjamin F. Loomis Historical Photograph Collection: Lassen Peak showing new lava flow on summit and large mudflows on slopes. Photo courtesy of NPS.
Lassen Peak photographed from the Devastated Area prior to 1914-191...
Lassen Peak photographed from the Devastated Area prior to the 1914-1915 eruption that changed the landscape.
Lassen Peak photographed from the Devastated Area prior to the 1914-1915 eruption that changed the landscape.
Related
What was the largest volcanic eruption in the 20th century?
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)...
Will extinct volcanoes on the east coast of the U.S. erupt again?
No. The geologic forces that generated volcanoes in the eastern United States millions of years ago no longer exist. Through plate tectonics, the eastern U.S. has been isolated from the global tectonic features (tectonic plate boundaries and hot spots in the mantle), that cause volcanic activity. So new volcanic activity is not possible now or in the near future. If you wait around several hundred...
Which volcanic eruptions were the deadliest?
Deadliest Volcanic Eruptions Since 1500 A.D. Eruption Year Casualties Major Cause Nevado del Ruiz, Colombia 1985 25,000 1,3 Mudflows 3 Mont Pelée, Martinique 1902 30,000 1 (29,025) 2 Pyroclastic flows 2 Krakatau, Indonesia 1883 36,000 1 (36,417) 2 Tsunami 2 Tambora, Indonesia 1815 92,000 1,2 Starvation 2 Unzendake, Japan 1792 15,000 1 (14,030) 2 Volcano collapse, Tsunami 2 Lakagigar (Laki)...
How Do Volcanoes Erupt?
Deep within the Earth it is so hot that some rocks slowly melt and become a thick flowing substance called magma. Since it is lighter than the solid rock around it, magma rises and collects in magma chambers. Eventually, some of the magma pushes through vents and fissures to the Earth's surface. Magma that has erupted is called lava. Some volcanic eruptions are explosive and others are not. The...
How many active volcanoes are there on Earth?
There are about 1,350 potentially active volcanoes worldwide, aside from the continuous belts of volcanoes on the ocean floor at spreading centers like the Mid-Atlantic Ridge. About 500 of those 1,350 volcanoes have erupted in historical time. Many of those are located along the Pacific Rim in what is known as the " Ring of Fire." In the United States, volcanoes in the Cascade Range and Alaska...
What was the most destructive volcanic eruption in the history of the United States?
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...
Where does the United States rank in the number of volcanoes?
The United States ranks third, behind Indonesia and Japan, in the number of historically active volcanoes (that is, those for which we have written accounts of eruptions). In addition, about 10 percent of the more than 1,500 volcanoes that have erupted in the past 10,000 years are located in the United States. Most of these volcanoes are found in the Aleutian Islands, the Alaska Peninsula, the...
Where is the largest active volcano in the world?
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
Are there earthquakes associated with Mount Hood?
Mount Hood is one of the most seismically active volcanoes in the Washington and Oregon Cascades, and the most seismically active volcano in Oregon. In an average month 1-2 earthquakes are located within 5 km (3 miles) of the summit. Earthquakes large enough to be felt occur on Mount Hood every two years on average. Seismic monitoring, in effect since 1977, indicates a generalized concentration of...
When did Lassen Peak last erupt?
The most recent eruptive activity at Lassen Peak (California) took place in 1914-1917. This eruptive episode began on May 30, 1914, when a small phreatic eruption occurred at a new vent near the summit of the peak. More than 150 explosions of various sizes occurred during the following year. By mid-May 1915, the eruption changed in character; lava appeared in the summit crater and subsequently...
How would an eruption of Mount Rainier compare to the 1980 eruption of Mount St. Helens?
Eruptions of Mount Rainier usually produce much less volcanic ash than do eruptions at Mount St. Helens. However, owing to the volcano's great height and widespread cover of snow and glacier ice, eruption triggered debris flows ( lahars) at Mount Rainier are likely to be much larger--and will travel a greater distance--than those at Mount St. Helens in 1980. Furthermore, areas at risk from debris...
How many eruptions have there been in the Cascades during the last 4,000 years?
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
A perspective view of Mount hood
A perspective view of Mount hood, made from the OR_Sandy_River_2007 lidar data
A perspective view of Mount hood, made from the OR_Sandy_River_2007 lidar data
USGS geologist viewing the northeastern slope of Mount Hood from Shellrock monitoring station.
PubTalk 04/2015—"Fearfully Grand" Eruptions: Lassen Peak, CA, 1914-17
Title: A Sight "Fearfully Grand" Eruptions of Lassen Peak, California, 1914 to1917
- A summary of the eruptions and their effects
- Illustrated with historical photographs
Title: A Sight "Fearfully Grand" Eruptions of Lassen Peak, California, 1914 to1917
- A summary of the eruptions and their effects
- Illustrated with historical photographs
Mount Hood dominates the skyline outside of Portland, Oregon
A major eruption of Mount Hood would pose a great hazard to the regional economy.
A major eruption of Mount Hood would pose a great hazard to the regional economy.
PubTalk 1/2012 — Lassen Volcanic National Park
--a wonderland of volcanoes and thermal features
By Patrick Muffler, Geologist Emeritus
--a wonderland of volcanoes and thermal features
By Patrick Muffler, Geologist Emeritus
Mount Hood, OR
View of Mount Hood from Pittock Mansion, Portland, OR.
View of Mount Hood from Pittock Mansion, Portland, OR.
Mount St. Helens: May 18, 1980
USGS scientists recount their experiences before, during and after the May 18, 1980 eruption of Mount St. Helens. Loss of their colleague David A. Johnston and 56 others in the eruption cast a pall over one of the most dramatic geologic moments in American history.
USGS scientists recount their experiences before, during and after the May 18, 1980 eruption of Mount St. Helens. Loss of their colleague David A. Johnston and 56 others in the eruption cast a pall over one of the most dramatic geologic moments in American history.
Mount St. Helens: A Catalyst for Change
The May 18, 1980 eruption of Mount St. Helens triggered a growth in volcano science and volcano monitoring. Five USGS volcano observatories have been established since the eruption. With new technologies and improved awareness of volcanic hazards USGS scientists are helping save lives and property across the planet.
The May 18, 1980 eruption of Mount St. Helens triggered a growth in volcano science and volcano monitoring. Five USGS volcano observatories have been established since the eruption. With new technologies and improved awareness of volcanic hazards USGS scientists are helping save lives and property across the planet.
Lassen Peak's Devastated Area photographed from the air in 1994.
Lassen Peak's Devastated Area photographed from the air in 1994.
Lassen Peak's Devastated Area photographed from the air in 1994.
Eruption of Mount St. Helens May 19, 1980
May 18, 1980 eruption of Mount St. Helens from southwest. Note the pyroclastic density currents spilling over the crater rim.
May 18, 1980 eruption of Mount St. Helens from southwest. Note the pyroclastic density currents spilling over the crater rim.
Mt. St. Helens before the eruption
Mt. St. Helens the day before the eruption, May 17, 1980.
Mt. St. Helens the day before the eruption, May 17, 1980.
Lava and mudflows from Lassen Peak, May 22, 1915
Benjamin F. Loomis Historical Photograph Collection: Lassen Peak showing new lava flow on summit and large mudflows on slopes. Photo courtesy of NPS.
Benjamin F. Loomis Historical Photograph Collection: Lassen Peak showing new lava flow on summit and large mudflows on slopes. Photo courtesy of NPS.
Lassen Peak photographed from the Devastated Area prior to 1914-191...
Lassen Peak photographed from the Devastated Area prior to the 1914-1915 eruption that changed the landscape.
Lassen Peak photographed from the Devastated Area prior to the 1914-1915 eruption that changed the landscape.
Updated Date: February 11, 2025