Thursday, December 26, 2013
A Moment of Volcanic Clarity: Rainier and St. Helens Show Themselves
Rainier is a huge mountain. It is 14,410 feet tall (4,392m), and is covered by 156 billion cubic feet of glacial ice. With its location so close to large population centers, it is one of the more dangerous of the Cascades volcanoes, although it hasn't been active in historical time. The last eruption was around 1,000 years ago. But a number of towns are built on mudflow deposits (lahars) from Rainier, highlighting the hazardous nature of the volcano.
2,500 years ago, a similar event took place, and several lakes were formed near the volcano. When one of the lakes overflowed and failed catastrophically, the ensuing flood carried debris downstream, blocking the drainage now covered by Silver Lake.
Several good paved highways approach the mountain, and several visitor centers can be found along Highway 504 above Interstate 5 on the west side of the volcano. We had little time for exploration, but we enjoyed the walk along Silver Lake, which is only five miles east of the Interstate.