The 50 Highest Cascade Volcanoes
(page created June 2000, last updated September 2004)
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This table lists the 50+ highest volcanoes in the Cascade Range. In general, only distinct
volcanoes (not individual peaks of volcanic origin) have been included in this list. However, several prominent
summits which are subsidiary peaks of a larger volcanic structure have been listed for reference, but without a
numerical rank. In order to consider two peaks as distinct volcanoes, this list requires that they have erupted
from separate vents and each have 1000 feet of reascent (prominence) above any intervening pass. This is a
rather strict standard, but it helps eliminate most subsidiary summits and satellite cinder cones from the list.
For example, Little Tahoma fails on both of the above criteria, while Shastina lacks only the necessary
reascent. For those summits which are part of a larger volcanic structure, the name of the encompassing
structure has been given in parentheses.
Of the 59 ranked volcanoes in this table, 27 are in Oregon and 19 in California, reflecting the
widespread and diverse volcanic activity in these states, while only 6 are in Washington and 7 in British
Columbia. Interestingly though, Washington has a majority of the very highest volcanoes, with 4 of the top 6
overall, although Oregon does hold a majority of the next highest peaks, having 10 of the top 16.
NOTE: I have compiled this list myself from a variety of sources, with elevations generally taken
from the current USGS topo maps for the US volcanoes
and the current NRCan topo maps for those in Canada. I
have calculated reascents (prominences) for these peaks myself from the topo maps, and they are necessarily
approximate in most cases. The ranking on this list is probably complete and accurate only down to 8500 feet.
Between 8500 and 7500 feet, there are dozens of volcanoes and volcanic peaks in southern Oregon and northern
California, most having reascents near or below 1000 ft, which makes compiling an accurate list very difficult.
Please contact me regarding any errors or suggestions. The only somewhat similar
list I know of is the USGS Volcanic Heights in the Western
United States, which does not concentrate on the Cascades and also admits to being very incomplete.
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| Footnotes: |
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| [1] |
Brokeoff Mountain is the highest remnant of Mount Tehama, the eroded ancestral stratovolcano above which the more
recent lava dome of Lassen Peak rises. Brokeoff has about 950 ft of reascent above the lowest saddle separating it
from Lassen Peak, so I am considering making an exception to the 1000 ft standard and giving it a separate ranking
of its own in this list. Other high remnants of Mount Tehama include Mount Diller (9087 ft), Loomis Peak (8658 ft),
and Mount Conard (8204 ft), but none of these have the necessary reascent and it is not readily determinable if they
erupted from separate vents. The eruptive center of Mount Tehama was probably near the location of the Sulphur Works
fumaroles.
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| [2] |
Mount Scott is the highest remnant of Mount Mazama, the volcano which collapsed following a cataclysmic eruption
7700 years ago to form Crater Lake. However, Mount Scott is a satellite cone on the east flank of the main Mazama
stratovolcano. The highest remnant of the main Mazama cone (and the highest point on the rim of Crater Lake) is
Hillman Peak, which has over 1400 ft of reascent above the lowest saddles (Kerr Notch and the Wineglass) along the
rim between it and Mount Scott. Thus these two peaks must receive separate rankings on this list.
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| [3] |
The Meager Volcanic Complex is the northernmost modern Cascade volcano, its lavas formed by Cascades arc subduction
but having erupted through the non-volcanic basement rocks of the Coast Mountains about 40 miles (65 km) NW of
Whistler. The complex consists of several overlapping stratovolcanoes and lava domes, and four of these peaks
(Plinth, Meager, Capricorn, and Pylon) have the necessary 1000 ft of reascent to be considered separate volcanoes on
this list. The Meager complex last erupted only 2300 years ago from a vent on the north side of Plinth Peak, so it
is merely dormant and likely to erupt again in the future. Older volcanic rocks and deposits found farther
northwest in the Coast Mountains may also have been associated with Cascades arc subduction (e.g. the Silverthrone
Caldera near Mount Waddington), but heavy glaciation has removed most of the evidence including the volcanic peaks
themselves, and present glaciers probably obscure additional evidence.
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| [4] |
Red Cinder is located on the eastern border of Lassen Volcanic National Park. There are several (at least 10)
volcanic peaks near it which exceed 7700 ft elevation, including cinder cones and eroded stratovolcano remnants.
However, none have 1000 ft of reascent from Red Cinder, and thus only Red Cinder has been included on this list.
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| [5] |
Gearhart Mountain is volcanic in origin, a large andesitic stratovolcano, but it is located over 75 miles (120 km)
east of the main Cascades arc and has an age greater than about 8 million years. Its formation is probably
associated with Basin and Range extension with no influence from Cascades arc subduction, and thus it is not a
"Cascade" volcano.
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| [6] |
Numerous Forest Service publications and roadside info boards claim that the Mountain Lakes Wilderness in southern
Oregon once contained a single massive 12000 ft high volcano, which had undergone a caldera-forming eruption similar
to Mount Mazama (Crater Lake) followed by subsequent glaciation which breached the caldera rim on several sides.
However, this is complete nonsense, misinformation invented by those with no scientific evidence to back their
fanciful claims. Although the view of the Mountain Lakes peaks from the Klamath Basin does appear to show a single
large decapitated mountain, the topographic map reveals that it actually consists of several (4 or 5) adjacent and
overlapping volcanoes, separated by large glacial troughs from the Ice Age which run down the intervening valleys.
Furthermore, none of the obvious evidence of a caldera-forming eruption has ever been found, such as thick welded
tuffs from pyroclastic flows, deep pumice/ash deposits nearby, and lighter tephra deposits covering a large
geographic area. Crater Lake produced all of these, Mountain Lakes none, so there never was a 12000 ft volcano or a
huge caldera-forming eruption in the Mountain Lakes region. Therefore these peaks (Aspen Butte, Mount Harriman,
etc.) will be referred to here in the plural as the Mountain Lakes Volcanoes.
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| [7] |
Yamsay Mountain and the better-known Newberry and Medicine Lake volcanoes are large shield volcanoes located about
30-40 miles (50-65 km) east of the main Cascades arc, along the edge of the Basin and Range geologic province.
However, their formation is believed to be linked to Cascades arc subduction, and most scientists consider them to
be "Cascade" volcanoes.
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| [8] |
Mount Cayley has no listed elevation on the current (1992) Natural Resources Canada 1:50,000 scale topographic map
92 J/3, and the highest contour shown on the peak is at 7800 ft. The elevation listed here comes from a 1991 Geological
Survey of Canada scientific paper, which gives the elevation as 2394 m.
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