Images

Plume within Mount St. Helens' crater, October 1, 2004 at 12:03:23 PDT.

Plume from Johnston Ridge Observatory, Mount St. Helens. October 1, 2004.

Mount St. Helens' dome and glacier uplift from the east, after steam and ash eruption.

Plume/crater image of Mount St. Helens October 1, 2004 at 12:03:55 PDT.

Mount St. Helens' dome and glacier uplift from the east, after steam and ash eruption.

Plume within Mount St. Helens' crater, October 1, 2004 at 12:03:32 PDT.

Plume/crater image of Mount St. Helens October 1, 2004 at 12:13 PDT.

Plume within Mount St. Helens' crater, October 1, 2004 at 12:16 PDT.

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. September 30, 2005

Close-in view of south side of Mount St. Helens lava dome, as seen from the southeast, showing the dome and part of the glacier forming at the base of the dome. September 2005

Western side of Mount St. Helens crater, and dome, showing the glacier forming at the base of the dome.

Mount St. Helens crater and dome as seen from SugarBowl, on the NE flank of the volcano. September 2005

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

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.

Map of volcanic ashfall. Areas of the United States that once were covered by volcanic ash from Yellowstone's giant eruptions 2 million and 630,000 years ago, compared with ashfall from the 760,000-year-old Long Valley caldera eruptions at Mammoth Lakes, California, and the 1980 eruption of Mount St. Helens, 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.

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.