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United States · Stratovolcano

Mount Jefferson

Jefferson

Type
Stratovolcano
Elevation
3199m
Last eruption
950
Mount Jefferson
Photo: Jsayre64 · CC BY-SA 3.0 · Wikimedia Commons
Type
Stratovolcano
Country
United States
Region
North America / High Cascades Volcanic Arc
Elevation
3199m
Coordinates
44.674, -121.800
Last eruption
950
Tectonic setting
Subduction zone / Continental crust (> 25 km)
Landform
Composite
Major rock type
Andesite / Basaltic andesite

Geological summary

Mount Jefferson, Oregon's second highest peak, is a deeply eroded stratovolcano. The glacier-clad landmark prominent from both sides of the Cascade Range was named by Lewis and Clark for the president that sponsored their expedition.

Excerpt from the Global Volcanism Program, Smithsonian Institution · Read the full summary on GVP →

From Wikipedia

Mount Jefferson is a stratovolcano in the Cascade Volcanic Arc, part of the Cascade Range in the U.S. state of Oregon. The second highest mountain in Oregon, it is situated within Linn County, Jefferson County, and Marion County and forms part of the Mount Jefferson Wilderness. Due to the ruggedness of its surroundings, the mountain is one of the hardest volcanoes to reach in the Cascades. It is also a popular tourist destination despite its remoteness, with recreational activities including hiking, backpacking, mountaineering, and photography. Vegetation at Mount Jefferson is dominated by Douglas fir, silver fir, mountain hemlock, ponderosa pine, lodgepole pine, and several cedar species. Carnivores, insectivores, bats, rodents, deer, birds, and various other species inhabit the area.

Wikipedia · CC BY-SA · Read full article →

Eruption history

2 recordedGlossary

Record summary

Confirmed eruptions
2
Uncertain eruptions
0
Span of confirmed record
4500 BCE (±50 yrs) – 950
Largest confirmed eruption
No VEI recorded
Confirmed eruptions since 1900
0
Summary (VEI over time)
Click a bar to see individual eruptions · Use arrow keys to move between bars, Enter to open
4500 BCE~4305 BCE · 1 eruptions · max VEI ?755~950 · 1 eruptions · max VEI ?4500 BCE3137 BCE1775 BCE607 BCE755

Detailed timeline

  1. 950VEI ?Geological estimate
    950 – end unknown
    S of Jefferson (South Cinder Peak)
  2. 4500 BCE (±50 yrs)VEI ?Geological estimate
    4500 BCE – end unknown
    SSE of Jefferson (Forked Butte)

Nearby volcanoes

External links

⚠ For reference only. Not for emergency response.