Grand Hogback

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Grand Hogback
Grand Hogback.JPG
Part of the Grand Hogback near New Castle, Colorado.
Highest point
Elevation 2,212 m (7,257 ft) [1]
Coordinates 39°37′07″N107°45′17″W / 39.61861°N 107.75472°W / 39.61861; -107.75472 Coordinates: 39°37′07″N107°45′17″W / 39.61861°N 107.75472°W / 39.61861; -107.75472
USA Colorado relief location map.svg
Red triangle with thick white border.svg
Grand Hogback
The Grand Hogback Monocline defines the eastern limit of the Uinta-Piceance Basin Uinta Piceance Basins geologic map.png
The Grand Hogback Monocline defines the eastern limit of the Uinta-Piceance Basin

The Grand Hogback is a 70-mile long, [2] curving, spine-like ridge in Western Colorado that extends from near McClure Pass in Pitkin County through Garfield County and then to near Meeker in Rio Blanco County. [3] The hogback is significant because it marks part of the boundary between the Colorado Plateau to the west and the Southern Rocky Mountains to the east. [4]


The elevation of the ridge ranges from 7,710 ft (2,350 m) to 9,194 ft (2,802 m). The hogback appears as a series of serrated ridges and is easily discernable from Google Maps and other aerial views. [4] It is visible from Interstate 70.


Rivers have carved out several gaps in the hogback, the most notable being the one the Colorado River has carved out near New Castle, Colorado. Others include Harvey Gap and Rifle Gap, [5] both of which have been dammed to create reservoirs and state parks.


A monocline, the Grand Hogback is part of the Mesaverde Formation. The ridge formed towards the end of the Laramide orogeny during the middle to late Eocene. [3]

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  1. "Grand Hogback". Geographic Names Information System . United States Geological Survey . Retrieved March 27, 2017.
  2. New Castle, Colorado. Living in New Castle. Retrieved: March 27, 2017.
  3. 1 2 Stracher, Glenn B.; et al. (2008). "Revisiting the South Cañon Number 1 Coal Mine fire during a geologic excursion from Denver to Glenwood Springs, Colorado". In Raynolds, Robert G. H. (ed.). Roaming the Rocky Mountains and Environs: Geological Field Trips. Geological Society of America. pp. 101–110. ISBN   9780813700106.
  4. 1 2 Colorado Mountain College. The Grand Hogback: Living life on the edge. Retrieved: March 27, 2017.
  5. Colorado Parks & Wildlife. Rifle Gap. Retrieved: March 27, 2017.