Grayrock Peak is a mountain
summit
A summit is a point on a surface that is higher in elevation than all points immediately adjacent to it. The topography, topographic terms acme, apex, peak (mountain peak), and zenith are synonymous.
The term (mountain top) is generally used ...
located in
San Juan County,
Colorado
Colorado (, other variants) is a state in the Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of t ...
, United States.
Description
Grayrock Peak is set west of the
Continental Divide
A continental divide is a drainage divide on a continent such that the drainage basin on one side of the divide feeds into one ocean or sea, and the basin on the other side either feeds into a different ocean or sea, or else is endorheic, not ...
in the
San Juan Mountains which are a subrange of the
Rocky Mountains
The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in straight-line distance from the northernmost part of western Canada, to New Mexico in ...
. It is situated north of the community of
Durango
Durango (), officially named Estado Libre y Soberano de Durango ( en, Free and Sovereign State of Durango; Tepehuán: ''Korian''; Nahuatl: ''Tepēhuahcān''), is one of the 31 states which make up the 32 Federal Entities of Mexico, situated in ...
on land managed by
San Juan National Forest. Grayrock is the highest point of Graysill Mountain.
Precipitation
runoff
Runoff, run-off or RUNOFF may refer to:
* RUNOFF, the first computer text-formatting program
* Runoff or run-off, another name for bleed, printing that lies beyond the edges to which a printed sheet is trimmed
* Runoff or run-off, a stock market ...
from the mountain drains into tributaries of the
Animas River
Animas River (''On-e-mas''; es, Río de las Ánimas) is a river in the western United States, a tributary of the San Juan River (Colorado River), San Juan River, part of the Colorado River, Colorado River System.
The Animas-La Plata Water Pro ...
.
Topographic relief is significant as the summit rises above Cascade Creek in less than two miles. Neighbors include
line parent A peak's line parent is the closest higher peak on the highest ridge leading away from the peak's "key col". A col is the lowest point on the ridge between two summits and is roughly synonymous with pass, gap, saddle and notch. The highest col of ...
Grizzly Peak to the north and
Engineer Mountain
Engineer Mountain is a mountain summit located in San Juan County, Colorado, United States. It is part of the San Juan Mountains range which is a subset of the Rocky Mountains, and is west of the Continental Divide. Engineer Mountain is a pro ...
, to the northeast.
An ascent of the peak involves hiking with 2,104-feet of elevation gain.
[John Peel, Paul Pixler (2020), ''Hiking Trails of Southwestern Colorado'', Fifth Edition, Graphic Arts Books, , p. 146.] The mountain's toponym was officially adopted in 1908 by the
United States Board on Geographic Names
The United States Board on Geographic Names (BGN) is a federal body operating under the United States Secretary of the Interior. The purpose of the board is to establish and maintain uniform usage of geographic names throughout the federal governm ...
.
Climate
According to the
Köppen climate classification
The Köppen climate classification is one of the most widely used climate classification systems. It was first published by German-Russian climatologist Wladimir Köppen (1846–1940) in 1884, with several later modifications by Köppen, notabl ...
system, Grayrock Peak is located in an alpine
subarctic climate
The subarctic climate (also called subpolar climate, or boreal climate) is a climate with long, cold (often very cold) winters, and short, warm to cool summers. It is found on large landmasses, often away from the moderating effects of an ocean, ge ...
zone with cold, snowy winters, and cool to warm summers.
Due to its altitude, it receives precipitation all year, as snow in winter and as thunderstorms in summer, with a dry period in late spring. Hikers can expect afternoon rain, hail, and lightning from the seasonal monsoon in late July and August.
Geology
Grayrock Peak is composed of
trachyte
Trachyte () is an extrusive igneous rock composed mostly of alkali feldspar. It is usually light-colored and aphanitic (fine-grained), with minor amounts of mafic minerals, and is formed by the rapid cooling of lava enriched with silica and al ...
, a light-colored
extrusive igneous rock
Igneous rock (derived from the Latin word ''ignis'' meaning fire), or magmatic rock, is one of the three main The three types of rocks, rock types, the others being Sedimentary rock, sedimentary and metamorphic rock, metamorphic. Igneous rock ...
composed mostly of
alkali feldspar
Feldspars are a group of rock-forming aluminium tectosilicate minerals, also containing other cations such as sodium, calcium, potassium, or barium. The most common members of the feldspar group are the ''plagioclase'' (sodium-calcium) feldspa ...
. This rock falls from the high walls of the north
cirque
A (; from the Latin word ') is an amphitheatre-like valley formed by glacial erosion. Alternative names for this landform are corrie (from Scottish Gaelic , meaning a pot or cauldron) and (; ). A cirque may also be a similarly shaped landform ...
and forms a
rock glacier
Rock glaciers are distinctive geomorphological landforms, consisting either of angular rock debris frozen in interstitial ice, former "true" glaciers overlain by a layer of talus, or something in-between. Rock glaciers are normally found at high ...
that descends 1,000 feet and extends three-quarters of a mile.
See also
*
*
References
External links
* Weather forecast
Grayrock PeakNational Geodetic Survey data sheet
{{Mountains of Colorado
Mountains of San Juan County, Colorado
San Juan Mountains (Colorado)
Mountains of Colorado
North American 3000 m summits
San Juan National Forest