How often does Mount Shasta erupt?

On average, Mount Shasta has erupted at least once every 800 years during the last 10,000 years, and about once every 600 years during the last 4,500 years. The last known eruption occurred about 200 years ago, possibly in 1786.

Eruptions during the last 10,000 years produced lava flows and domes on and around the flanks of Mount Shasta. Pyroclastic flows from summit and flank vents extended as far as 20 km (12.4 mi) from the summit. Most of these eruptions also produced large mudflows, many of which travelled several tens of kilometers from Mount Shasta.

Learn more at the website for the USGS California Volcano Observatory.

Related Content