Glacier Peak is a small stratovolcano in the Cascade Range of Washington. There are over one dozen glaciers on the sides of this volcano. Most of the loose pyroclastic deposits have been eroded by these glaciers. The tops of the ridges to the northeast of the volcano are covered by lava flows. Small basaltic flows and cones can be found around the sides of Glacier Peak. Lava flows only extend a few km from the top of the volcano.
Three hot springs flow from the ground around the volcano. Fresh looking dacite domes are positioned high on the north and south sides of the volcano. Warm ground and areas without snow surround these domes. Large fans of pyroclastic materials almost entirely fill the valleys on the east and west sides of the volcano.
Most of the eruptions from Glacier Peak have been tephra eruptions. Two tephra layers from the volcano stretch up to 500-600 miles (800-1000 km) to the east. These layers were deposited about 11,250 years ago.
Sources of Information:
Wood, Charles A. and Kienle, Jurgen, "Volcanoes of North America," Cambridge University Press, Cambridge, 354 pp., 1990.