Mount Shasta

   

Mount Shasta
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Mount Shasta and Shastina from the northwest
Elevation:14,179 ft (4,322 m)
Latitude:41° 24′ 33.11″ N
Longitude:121° 11′ 41.60″ W
Location:California, USA
Topo map:USGS Mount Shasta
Range:Cascades
Type:Composite volcano
Age of rock:< 593 Kyr
First ascent:1854 by E.D. Pearce and party
Easiest route:rock/ice climb


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 mile&sup3 (450 km&sup3).

Geology

Main article: Geology of Mount Shasta

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.

Views

Shastina with Mt. Shasta behind
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Shastina with Mt. Shasta behind
Mt. Shasta
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Mt. Shasta
Little Glass Mountain and Mt Shasta
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Little Glass Mountain and Mt Shasta
Mt. Shasta from the air
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Mt. Shasta from the air


External link




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