Active and Potentially Active Volcanoes
in California
-- From: Wright and Pierson, 1992,
Living with Volcanoes, The U.S.Geological Survey's Volcano Hazards Program: USGS Circular 1073, 57p
Eruption
type(s)
Number of
eruptions
in past 200
years
Latest
activity (in
years
before
present or
year(s)
A.D.)
Medicine
Lake
Ash, lava
0
1065
Latest eruption formed
Glass Mountain
Mount
Shasta
Ash,
dome
1
1786?
Debris flows in this
century
Lassen Peak
Ash,
dome
1
1914-1917
Lateral blast occurred in
last eruption
Not known
Geothermal energy and
long-period (volcanic)
seismicity suggest
"active" status.
3?
About 1400
Youngest activity
represented by nearly
simultaneous eruptions
of rhyolite at several of
the Inyo craters;
currently restless, shown
by seismicity and ground
deformation
0
About
40,000
years ago
Geothermal energy
production and seismic
activity suggest "active"
status
Volcano
Clear Lake
Lava, ash
Long Valley
Caldera
(including
Inyo, Mono,
Mammoth)
Ash,
dome,
ashflow
Coso Peak
Lava, ash,
dome
0
Remarks