Following unrest that began on September 23, 2004 and the steam and ash eruptions in early October, extrusion of solid magma typified the 2004-2008 eruption at Mount St. Helens. The magma is unusually gas poor and crystal rich. Several meters of pulverized, variably sintered rock commonly coat the emergent lava spines, lending them a smooth appearance.
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Mount St. Helens: Instrumentation and Dome Growth, Oct 2004-Sept 2005
Following unrest that began on September 23, 2004 and the steam and ash eruptions in early October, extrusion of solid magma typified the 2004-2008 eruption at Mount St. Helens. The magma is unusually gas poor and crystal rich. Several meters of pulverized, variably sintered rock commonly coat the emergent lava spines, lending them a smooth appearance.
October 1, 2004 Explosion at Mount St. Helens
On October 1, 2004, an explosion in the crater of Mount St. Helens sent ash and water vapor several thousand feet into the air. It was the dramatic beginning of an eruption that continued for the next 3+ years. The explosion fractured Crater Glacier and hurled rocks for at least one-half mile across the western half of the glacier and the 1980-1986 lava dome.
On October 1, 2004, an explosion in the crater of Mount St. Helens sent ash and water vapor several thousand feet into the air. It was the dramatic beginning of an eruption that continued for the next 3+ years. The explosion fractured Crater Glacier and hurled rocks for at least one-half mile across the western half of the glacier and the 1980-1986 lava dome.
May 18, 1980 Mount St. Helens Eruption: Stories from USGS Scientists
USGS scientists C. Dan Miller, Don Mullineaux, Mike Doukas, Norm Banks, Don Swanson, and Richard Waitt talk about their experiences at Mount St.
USGS scientists C. Dan Miller, Don Mullineaux, Mike Doukas, Norm Banks, Don Swanson, and Richard Waitt talk about their experiences at Mount St.
Mount St. Helens in eruption, May 18, 1980
Mount St. Helens erupted catastrophically on May 18, 1980 beginning at 8:32 a.m. USGS geologist Don Swanson photographed and filmed the eruption from about 9:30 a.m. to 12:30 p.m., documenting the rising ash column and ground-hugging pyroclastic density currents.
Mount St. Helens erupted catastrophically on May 18, 1980 beginning at 8:32 a.m. USGS geologist Don Swanson photographed and filmed the eruption from about 9:30 a.m. to 12:30 p.m., documenting the rising ash column and ground-hugging pyroclastic density currents.
Mount St. Helens 1980 Ash Cloud as Seen From Space
Eruptive activity at Mount St. Helens captured the world’s attention on May 18, 1980 when the largest historical landslide on Earth and a powerful explosion reshaped the volcano. A volcanic ash cloud spread across the US in 3 days, and encircled the Earth in 15 days.
Eruptive activity at Mount St. Helens captured the world’s attention on May 18, 1980 when the largest historical landslide on Earth and a powerful explosion reshaped the volcano. A volcanic ash cloud spread across the US in 3 days, and encircled the Earth in 15 days.