Images

Berm from a 1997 lahar is visible along the channel. Mount St. Helens' east crater wall is visible in the background.

South side of Mount St. Helens lava dome, as seen from the east, showing the dome and part of the glacier forming at the base of the dome. August 29, 2005

Roaring Spring on the McKenzie River, Oregon

Image of the Western Fisheries Research Center, Marrowstone Marine Field Station.  Looking east toward Puget Sound.

Northeast crater wall above Sugar Bowl, Mount St. Helens with annotated deposits from some of the Spirit Lake Stage eruptive periods. Photograph from late summer 2003.

Sagebrush-dominated ecoregions in the western United States (sagebrush cover types shown in various shades of yellow, pink, and blue-grey).

During Ocean Drilling Program Leg 204, nine sites were cored and wireline logged on the Oregon continental margin to determine the distribution and concentration of gas hydrates in an accretionary ridge setting, investigate the mechanisms that transport methane and other gases into the gas hydrate stability zone, and obtain constraints on physical properties of

USGS scientist collecting samples at Crater Lake, Oregon.

Photograph showing the scar left by a landslide on a hillside above the Burlington Northern Santa Fe Railway in Everett, Washington.

Photograph showing a house that was damaged by a 1997 landslide along Perkins Lane in Seattle, Washington.

Angle and distance measurements to the Mount St. Helens' flanks were taken periodically to monitor for deformation similar to the 1980 bulge. Station northeast of volcano.

Deformation measurements on the Mount St. Helens' dome; three geologists in middle bottom of this aerial photograph.

The last dome-building eruption of Mount St. Helens during the 1980s occurred in October 1986. A new lobe was extruded, increasing the dome's height to 925 feet (282 meters), making it taller than a 77-story building. In volume, the dome was nearly 40 times the size of Seattle's Kingdome stadium.

View of the Spirit Lake outlet tunnel, built in 1985, that allows water to drain out of Spirit Lake safely and maintain the lake's water level 100 ft (30 m) below the estimated overtopping level.

Three Sisters volcanoes (left to right - South, Middle, and North) viewed from the south, Oregon. Foreground rhyolite Newberry flow is one of most recent eruptive units (2.2 ka).

The lava dome was taller than a 66-story building and almost as wide as the length of nine football fields. The dome completely fills the camera's field of view. Compare with image taken August 22, 1981 from the same location with the same camera.

Mount St. Helens four years after the May 18, 1980 eruption—lava dome in the crater and drainage channels development on flanks; view from Johnston Ridge.

Vegetation began reappearing as early as the summer of 1980 as many small trees and plants were protected by the snowpack on May 18. Seeds, carried by the wind or by animals, also entered the area and grew. By 1985, the ridges surrounding the volcano were covered with new growth.

The strength of the magnetic field increased as the dome cooled and magnetic minerals formed. During the eruptions the strength usually changed rapidly as magma heated and deformed the dome.

Harry's Ridge monitoring station, 8 km (5 mi) north of Mount St. Helens' crater.