Big Southern Butte is the largest and youngest (300,000 years old) of three
rhyolitic
Rhyolite ( ) is the most silica-rich of volcanic rocks. It is generally glassy or fine-grained (aphanitic) in texture, but may be porphyritic, containing larger mineral crystals (phenocrysts) in an otherwise fine-grained groundmass. The mineral ...
domes formed over a million years near the center of the Eastern
Snake River Plain
image:Snake River view near Twin Falls, Idaho.jpg, The Snake River cutting through the plain leaves many canyons and Canyon#List of gorges, gorges, such as this one near Twin Falls, Idaho
The Snake River Plain is a geology, geologic feature ...
in the
U.S. state of
Idaho
Idaho ( ) is a state in the Pacific Northwest region of the Western United States. To the north, it shares a small portion of the Canada–United States border with the province of British Columbia. It borders the states of Montana and Wyom ...
. It is one of the largest volcanic domes on earth.
It rises approximately 2500 vertical feet (762 m) above the lava plain in southern
Butte County, east of
Craters of the Moon Craters of the Moon may refer to:
* Lunar craters, craters on the Earth's Moon
* Craters of the Moon National Monument and Preserve, a volcanic preserve in Idaho
* Craters of the Moon (geothermal site)
Craters of the Moon Thermal Area (or ''Kara ...
National Monument
A national monument is a monument constructed in order to commemorate something of importance to national heritage, such as a country's founding, independence, war, or the life and death of a historical figure.
The term may also refer to a spec ...
.
Big Southern Butte consists of two coalesced
lava dome
In volcanology, a lava dome is a circular mound-shaped protrusion resulting from the slow extrusion of viscous lava from a volcano. Dome-building eruptions are common, particularly in convergent plate boundary settings. Around 6% of eruptions on ...
s with a base diameter of and a combined volume of approximately .
See also
*
East Butte
*
Middle Butte
Gallery
File:Big Southern Butte.jpg, Big Southern Butte
File:Big Southern Butte, aerial.jpg, Aerial view from southwest
References
External links
History of the Big Southern Butte areaTourofidaho.com: Big Southern Butte − on the Tour of Idaho
Pleistocene lava domes
Volcanoes of Idaho
Volcanoes of the Rocky Mountains
Landforms of Butte County, Idaho
National Natural Landmarks in Idaho
Protected areas of Butte County, Idaho
Bureau of Land Management areas in Idaho
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