Needle Rock Natural Area

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Needle Rock
Needle Rock is located in Colorado
Needle Rock
Needle Rock
Colorado
Elevation 7,797 ft (2,377 m)[2][1]
Location
Location Delta County, Colorado, U.S.[1]
Range West Elk Mountains
Coordinates 38°43′28″N 107°33′00″W / 38.7244335°N 107.5500571°W / 38.7244335; -107.5500571Coordinates: 38°43′28″N 107°33′00″W / 38.7244335°N 107.5500571°W / 38.7244335; -107.5500571[1]
Topo map USGS 7.5' topographic map
Crawford, Colorado[1]
Geology
Type Composite volcano
Age of rock c.a. 28 Ma
Climbing
Easiest route rock

Needle Rock is an intrusive of rhyodacite volcanic plug[3] located in the Needle Rock Natural Area, 3.5 miles (5.6 km) east-northeast (bearing 68°) of the Town of Crawford in Delta County, Colorado, United States. It stands 800 feet (240 m) tall above the floor of the Smith Fork of the Gunnison River valley. It originated as the throat of a large volcano about 28 million years ago in the Miocene geological epoch, when molten rock intruded between existing sedimentary rocks.[4] The plug may represent the eroded conduit of a laccolith.[3]

See also[edit]

References[edit]

  1. ^ a b c d "Needle Rock". Geographic Names Information System. United States Geological Survey. Retrieved November 6, 2014. 
  2. ^ The elevation of Needle Rock includes an adjustment of +1.473 m (+4.83 ft) from NGVD 29 to NAVD 88.
  3. ^ a b "MINERAL RESOURCES OF THE WEST ELK WILDERNESS and vicinity, Delta and Gunnison Counties, Colorado: Open-file report 77-751" (PDF). DEPARTMENT OF THE INTERIOR: UNITED STATES GEOLOGICAL SURVEY. 1977. pp. 16, 85, 98. 
  4. ^ "America's Volcanic Past: Colorado". Vancouver, Washington: USGS: Cascades Volcano Observatory (CVO).  |chapter= ignored (help)

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