Lava Butte
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| Lava Butte | |
|---|---|
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| Elevation | 5,020 feet (1,530 m)[1] |
| Location | Deschutes County, Oregon, USA |
| Prominence | 509 feet (155 m) |
| Coordinates | [2] |
| Topo map | USGS Lava Butte |
| Type | Cinder cone |
| Age of rock | about 7,000 years |
| Last eruption | about 7,000 years ago |
| Easiest route | Road |
Lava Butte is a cinder cone located in central Oregon, USA, just west of US Highway 97 between the towns of Bend, Oregon, and Sunriver, Oregon. About 500 feet (150 m) tall, it is part of a system of small cinder cones on the northwest flank of Newberry Volcano, a massive shield volcano which rises to the southeast. The cinder cone is capped by a crater which extends about 60 feet (20 m) deep beneath its south rim, and 160 feet (50 m) deep from the 5,016 ft (1,529 m) summit on its north side. Lava Butte is part of the Newberry National Volcanic Monument.
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[edit] Volcanic history
Like the other cinder cones in the area, Lava Butte only experienced a single eruption, dated by geologists in 1977 to 6,150 carbon-14 years, equivalent to about 7,000 years ago. The eruption began with a fissure spewing hot cinders to form the cone. In the next phase, a river of hot basalt flowed from the base of the small volcano to cover a large area to the west with a blocky lava flow which remains largely free of vegetation. The lava flows reached the Deschutes River about 2.5 miles (4.0 km) to the west of the cone, burying its former channel under over 100 feet (30 m) of lava and damming the river to form a lake, known as Lake Benham. The river eventually overflowed the lava dam and eroded down into it, draining the lake and forming Benham Falls. Geologists estimate that 90% of the magma erupted as lava flows, 9% as scoria which forms the cone, and 1% as volcanic ash which forms a thin layer extending to the north.
[edit] Human history
The early history of Lava Butte is not known, but it is assumed that Native Americans observed the eruptions and later ascended the prominent new landmark. White settlers arriving in the 1800s also noted the landmark. In September 1914, Lava Butte "erupted" when the Bend Chamber of Commerce simulated an eruption to surprise a visiting Portland group. In 1925, USGS geologist Harold Stearns studied the Newberry area, and recognized the fissure system which extends from Lava Butte to East Lake within Newberry Caldera.
The cinder cone was also exploited to some extent for its economic value. In June 1926, a quarry was developed in fault scarp east of Lava Butte as a source for paving material for the first The Dalles-California Highway (later U.S. Route 97). In November 1929, cinders from Lava Butte were shipped to Longview, Washington, to be used in construction of Longview Bridge across Columbia River.
A United States Forest Service fire lookout tower was built on the summit in 1931, and in early 1933 a steep, single-lane road was constructed spiraling up to the summit. In February of that year, the local Skyliners ski club proposed a ski jump on Lava Butte, but it was never built. In June 1946, widening of the road up Lava Butte to two lanes was completed, along with constructing two small parking lots at the summit. The road was later paved in July 1950. The original lookout was replaced with a larger one in 1957, which was subsequently enlarged in 1962 to accommodate a small visitor center and museum on the first floor. In 1998, this was replaced with a new lookout built in the original L-4 style of 1931.
In July 1966, twenty-two astronauts trained in Central Oregon for the upcoming Moon landings, at sites including Lava Butte, Lava River Cave, and Newberry Crater. In May 1967, the U.S. Forest Service created the 8,983 acre Lava Butte Geological Area to protect the cinder cone, with plans for recreational and interpretive development. Construction of the Lava Lands Visitor Center located just south of the cone began in April 1969, and it was finally dedicated in September 1975. In November 1990, Newberry National Volcanic Monument was created, encompassing Newberry Crater, Lava Cast Forest Geological Area, Lava River Cave, and the Lava Butte Geological Area.
[edit] References
- ^ NGS Data Sheet for LAVA BU RESET. U.S. National Geodetic Survey. Retrieved on 2008-04-01.
- ^ Computed from NGS Data Sheet
- Lava Butte Vicinity, Oregon. USGS Cascades Volcano Observatory. Retrieved on 2008-04-01.
- Harris, Stephen L. (2005). Fire Mountains of the West: The Cascade and Mono Lake Volcanoes (3rd ed.). Mountain Press Publishing Company, p. 177–8. ISBN 0-87842-511-X.
- Wood, Charles A.; Jürgen Kienle, eds. (1990). Volcanoes of North America. Cambridge University Press, p. 202. ISBN 0-521-43811-X.
- Deschutes & Ochoco National Forests: Histery. US Forest Service. Retrieved on 2008-04-01.
- Kresek, Ray (1998). Fire Lookouts of the Northwest (3rd ed.). Historic Lookout Project. ISBN 0-87770-632-8.
- Lava Butte Lookout. National Historic Lookout Register. Retrieved on 2008-04-01.</ref>
[edit] External links
- Newberry National Volcanic Monument. US Forest Service. Retrieved on 2008-04-01.
- Architectural drawing of 1957 Lava Butte Lookout Tower. US Forest Service. Retrieved on 2008-04-01.
