La Garita Mountains

La Garita Mountains
Silver Park in the La Garita Mountains
Highest point
PeakPhoenix Peak
Elevation13,895 ft (4,235 m)[1]
Coordinates37°56′11″N 106°51′59″W / 37.9363901°N 106.8662693°W / 37.9363901; -106.8662693[1]
Geography
La Garita Mountains is located in Colorado
La Garita Mountains
La Garita Mountains
CountryUnited States
StateColorado
CountiesSaguache and Mineral
Parent rangeSan Juan Mountains, Rocky Mountains

The La Garita Mountains are a high mountain range in the San Juan Mountains, a sub-range of the Southern Rocky Mountains. The mountains are located in Saguache and Mineral counties in southwestern Colorado and are almost entirely managed as public land within the Rio Grande National Forest.[1]

The La Garita Mountains extend from near the town of Creede east and northeast over 30 miles (48 km) toward the San Luis Valley. The range is marked by a circuitous ridge with the westernnmost peak being Phoenix Peak (elevation 13,895 feet (4,235 m)) near the Continental Divide and the easternmost peak being Lookout Mountain (elevation 11,516 feet (3,510 m)) near Carnero Pass.[1]

La Garita means 'the lookout' in Spanish. Along this range climbers can look south across the upper Rio Grande Valley and east across the San Luis Valley.

The western third of the La Garita Mountains is protected within the La Garita Wilderness, one of Colorado's lesser-known wilderness areas. Travel in the wilderness is restricted to those on foot and horseback, while the remainder of the range is more accessible with multiple roads allowing mechanized travel. The range includes montane and subalpine forests and meadows and alpine tundra that provide ideal habitats for elk and mule deer.[2][3]

Geology

The La Garita Mountains are dominated by Tertiary volcanic rocks, including lavas, ash flow tuffs, and breccias. These materials originated from over a dozen volcanoes and multiple eruptions in the San Juan volcanic field. The rocks exposed today are from eruptions 35 million years ago to 26 million years ago.[4][5]

After major eruptions emptied the magma chamber below these volcanoes, the overlying rock could collapse and produce a sunken crater called a caldera. Evidence of such calderas are found throughout the San Juan Volcanic Field, including where the La Garita Mountains occur today. One of the largest of these volcanoes was the La Garita Caldera, which is located on the western extent of the La Garita Mountains. It was active 27.8 million years ago, and within this caldera, later eruptions (27.3 million years ago) produced the Bachelor Caldera. Through time, these calderas have filled with additional volcanic material ejected from other volcanoes, and subsequent erosion has reshaped the landscape making the ancient calderas now difficult to detect.[6][7]

Evidence of glaciation is present at the highest elevations of the La Garita Mountains. Glacial cirques are particularly evident along the higher, western extent of the range where tarns and glacial deposits are found.[4][6]

The Wheeler Geologic Area, located along the northeast wall the Bachelor Caldera, is noted for its eroded and exposed layers of volcanic tuff that filled the caldera. This 27 million year old tuff was ejected from eruptions in the San Luis Caldera Complex located north of the La Garita Mountains.[6]

Climate

The climate of the La Garita Mountains is classified in the Köppen system as a subarctic climate (Dfc) at lower elevations and a tundra climate (ET) above treeline, with cold, snowy winters and cool summers. It receives precipitation as snow in winter and as thunderstorms in summer, with June typically being a drier month.[8][9][10]

Mountains

Notable summits along the La Garita Mountains’ ridge, as delineated by the United States Board on Geographic Names, from west to east.[1]

  • Phoenix Peak, 13,895 feet (4,235 m) – highest summit in the La Garita Mountains
  • La Garita Peak, 13,710 feet (4,179 m)
  • Mesa Mountain, 12,944 feet (3,945 m)
  • Bowers Peak, 12,458 feet (3,797 m)
  • Lookout Mountain, 11,516 feet (3,510 m)
  • Unnamed Peak 11,021, 11,021 feet (3,359 m)

References

  1. ^ a b c d e "La Garita Mountains". Geographic Names Information System. United States Geological Survey, United States Department of the Interior. Retrieved 17 March 2024.
  2. ^ "La Garita Wilderness". Wilderness Net. Retrieved 22 May 2020.
  3. ^ Warren, Scott S. (2002). Exploring Colorado's Wild Areas: A Guide for Hikers, Backpackers, Climbers, X-C Skiers, and Paddlers (2nd ed.). Seattle, Washington: The Mountaineers. ISBN 0898867843.
  4. ^ a b Cappa, J.A.; Wallace, C.A. (1999). Geology and Mineral Resources of Saguache County, Colorado. Resource Series RS-44. Denver, Colorado: Colorado Geological Survey.
  5. ^ Tweto, Ogden (1979). "Geologic map of Colorado". United States Geological Survey. Retrieved 4 March 2024.
  6. ^ a b c Lipman, Peter W. (2006). Geologic map of the central San Juan caldera cluster, southwestern Colorado. Geologic Investigations Series Map I-2799. United States Geological Survey.
  7. ^ Morgan, Leah E.; Johnstone, Samuel A.; Gilmer, Amy K.; Cosca, Michael A.; Thompson, Ren. A. (2019). "A supervolcano and its sidekicks: A 100 ka eruptive chronology of the Fish Canyon Tuff and associated units of the La Garita magmatic system, Colorado, USA". Geology. 47 (5). Geological Society of America: 453–456. doi:10.1130/G45898.1. ISSN 1943-2682. Retrieved February 8, 2024.
  8. ^ Doesken, Nolan J.; Pielke, Sr., Roger A.; Bliss, Odilia A. P. (2003). "Climate of Colorado". Fort Collins, Colorado: Colorado Climate Center. Retrieved 4 March 2024.
  9. ^ Beck, H.E.; et al. (2023). "High-resolution (1 km) Köppen-Geiger maps for 1901–2099 based on constrained CMIP6 projections". Scientific Data. 10 (724). doi:10.1038/s41597-023-02549-6. PMC 10593765. Retrieved 24 March 2024.
  10. ^ "Climate zones on the move: Historical and predicted future changes in the global distribution of Köppen-Geiger climate zones". Canberra, Australia: Haizea Analytics. Retrieved 24 March 2024.