What kind of volcano is Mount Saint Helens?

Location: State of Washington, USA Latitude and Longitude: 46.2º N, 122.2º W, Elevation: 2,549 m (8,363 ft) Volcano Type: Stratovolcano Earliest Eruption: 10,000 BP Oldest Historic Eruption: 1831. Most Recent Eruption: 2008. Number of Eruptions in 20th Century: 5. read more

Mount St. Helens was formed during four eruptive stages beginning about 275,000 years ago and has been the most active volcano in the Cascade Range during the Holocene. Prior to about 12,800 years ago, tephra, lava domes, and pyroclastic flows were erupted, forming the older St. Helens edifice, but a few lava flows extended beyond the base of the volcano. read more

The Mount St. Helens National Volcanic Monument was created to preserve the volcano and allow for its aftermath to be scientifically studied. As with most other volcanoes in the Cascade Range, Mount St. Helens is a large eruptive cone consisting of lava rock interlayered with ash, pumice, and other deposits. read more

Notable Feature(s): During the 1980 eruption, the "Bulge" on north face, lateral blast removed the upper 396 m (1,306.8 ft) of the volcano. Notable Statistic: The May 18, 1980 blast devastated 596 square kilometers (229 square miles) and destroyed timber valued at several million dollars. read more