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MOUNT SHASTA CITY, CALIFORNIA - USA
Mount Shasta, a 14,179 ft (4,322 m) stratovolcano, is the second highest
peak in the Cascade Range and the second highest point in California (after
Mount Whitney). The mountain stands 10,000 ft (3,000 m) above the
surrounding area and has an estimated volume of 108 mile³ (450 km³).
Geology
The mountain consists of four separate cones buried atop one another.
Shastina 12,300 ft (3,749 m) is the most obvious cone and forms a lesser
summit. It has a fully intact summit crater which shows that Shastina
postdates the last ice age. The rest of Shasta's surface is relatively free
of glacial erosion except, paradoxically, for its south side where Sargents
Ridge runs parallel to the U-shaped Avalanche Gulch (the largest glacial
valley on the volcano, although it does not presently have a glacier in it).
There are five named, yet tiny, glaciers clustered on the mountain's north
side.
Shasta receives much less snow than most other Cascade mountains because of
its southerly position and the fact that moisture-laden air from the Pacific
Ocean must first surmount the Klamath Mountains before it reaches Shasta.
The annual snowline on Shasta is therefore above 10,000 ft (3,000 m).
There are many buried glacial scars on the mountain that were originally
excavated in glacial periods ("ice ages") of the present Wisconsonian
glaciation. Most have since been filled-in with andesite lava, pyroclastic
flows, and talus from lava domes.
Volcanic hazards
During the last 10,000 years Shasta has erupted an average of every 800
years but in the past 4500 years the volcano has erupted an average of every
600 years. The last significant eruption on Shasta may have occurred 200
years ago.
Mount Shasta can release volcanic ash, pyroclastic flows or dacite and
andesite lava. Its deposits can be detected under two nearby small towns
totalling 20,000 in population. Shasta has an explosive, eruptive history.
There are fumaroles on the mountain, which shows that Shasta is still alive.
The worst case scenario for an eruption is a large pyroclastic flow, such as
what occurred at Mount St. Helens. Since there is ice, lahars would also
result. Ash would probably blow inland, perhaps as far as eastern Nevada.
There is a small chance that an eruption could also be bigger resulting in a
collapse of the mountain, as happened at Crater Lake in Oregon, but this is
of much lower probability.
The US Geologic Survey considers Shasta a volcano with a high probability of
erupting again.
Religion
Native American lore of the area held that Shasta is inhabited by the spirit
chief Skell who descended from heaven to the mountain's summit. Since then
many other faiths and cults have been attracted to Shasta (more than any
other Cascade volcano). Mt. Shasta, California, a small town near Shasta's
western base, is a focal point for many of these religions. Some examples:
Association Sananda and Sanat Kemara, I AM Foundation, Knights of the White
Rose, Radiant School of the Seekers and Servers, Rosicrucians, and
Understanding, Inc.. Many of these cults hold that races of sentient beings,
obstensibly superior to humans, live on Shasta or visit the mountain in UFOs.
There are in fact disk or lens-shaped clouds that form sometimes over the
mountain—a fairly typical meteorological phenomenon over high places on the
earth. Lenticular clouds are often seen and mistaken for UFOs.
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