Broken Top

Infobox Mountain
Name = Broken Top
Photo = Broken Top.jpg
Caption =
Elevation = convert|9175|ft|m [ cite web
url = http://nwdata.geol.pdx.edu/OR-GIS/PlaceNames/B.html
title = Northwest GeoData Clearinghouse
publisher = Department of Geology: Portland State University
accessdate = 2008-03-31 ]
Location = Deschutes County, Oregon, USA
Range = Cascade Range
Prominence = convert|2175|ft|m cite web
url = http://www.peakbagger.com/peak.aspx?pid=2420
title = Broken Top
publisher = Peakbagger.com
accessdate = 2008-03-31 ]
Coordinates = coord|44.0828931|-121.6997595|format=dms|region:US_type:mountain [GNIS|1138649accessdate|2008-03-31]
Topographic
USGS Broken Top
Type = Stratovolcano
Volcanic_Arc/Belt = Cascade Volcanic Arc
Age = Pleistocene
Last eruption = about 100,000 years ago cite web
title = Deschutes & Ochoco National Forests - Broken Top Volcano
publisher = USDA Forest Service
date = 2003-11-26
url = http://www.fs.fed.us/r6/centraloregon/geology/info/volcanoes/brokentop.shtml
accessdate = 2008-03-18 ]
First ascent =
Easiest route =

Broken Top is a stratovolcano highly eroded by glaciation.cite book | last = Wood | first = Charles A. | coauthors = Jűrgen Kienle | title = Volcanoes of North America | publisher = Cambridge University Press | date = 1993 | pages = p. 183 | isbn = 0-512-43811-X ] It is located south of the Three Sisters group of volcanoes in the Cascade Range of central Oregon and within the Three Sisters Wilderness.cite web | title = Three Sisters Wilderness | work = Willamette National Forest | publisher = United States Forest Service | date = 2004-07-29 | url = http://www.fs.fed.us/r6/willamette/recreation/tripplanning/wilderness/threesisters.html | accessdate = 2008-05-18] Broken Top is about 20 miles (32 km) west of Bend, Oregon in Deschutes County.

Geology

Pleistocene eruptions originally created a broad shield of basaltic andesite. Intermittently, more silicic magma was erupted, ranging from andesite to dacite to rhyodacite. Intrusive dikes and pyroclastic flow deposits can also be found in the layers of Broken Top's flanks. Ice Age glaciers have carved into the volcano on three sides, exposing its internal structure. cite web
url = http://vulcan.wr.usgs.gov/Volcanoes/BrokenTop/description_broken_top.html
title = Broken Top Volcano, Oregon
publisher = USGS Cascades Volcano Observatory
accessdate = 2008-03-18 ]

See also

* Cascade Volcanoes
* Geology of the Pacific Northwest

References

External links

* cite web
url = http://www.summitpost.org/show/mountain_link.pl/mountain_id/454
title = Broken Top
publisher = Summitpost.org
accessdate = 2008-03-18