View source for Earth:Red Mountain (Coconino County, Arizona)

{{Short description|Volcanic cinder cone in Coconino County, Arizona, US}}
{{Infobox mountain
| name = Red Mountain
| other_name =
| photo = Red Mountain, Arizona.jpg
| photo_alt =
| photo_caption = Red Mountain in winter. Snow outlines the eroded amphitheater, which may have resulted from a steam-blast explosion
| elevation_ft = 7968
| elevation_ref = {{ngvd29}}<ref name="pb">{{cite peakbagger |pid=3936 |name=Red Mountain, Arizona |accessdate=2016-08-24}}</ref>
| prominence_ft = 1005
| prominence_ref = <ref name="pb"/>
| range =
| listing =
| parent_peak =
| location = Coconino County, Arizona, U.S.
| map = USA Arizona
| map_caption = none
| map_size = 180
| label =
| label_position =
| coordinates = {{coord|35.5230589|N|111.8754372|W|type:mountain_region:US-AZ_scale:100000_source:GNIS|format=dms|display=inline,title}}
| range_coordinates =
| coordinates_ref = <ref name="gnis">{{cite gnis |id=33486 |name=Red Mountain |accessdate=2016-08-24}}</ref>
| topo = USGS Chapel Mountain
| volcanic_field = [[Earth:San Francisco volcanic field|San Francisco volcanic field]]
| type= [[Earth:Cinder cone|cinder cone]]
| last_eruption =
| first_ascent =
| easiest_route =
}}
'''Red Mountain''' is a volcanic [[Earth:Cinder cone|cinder cone]] located in the Coconino National Forest of northern Arizona, United States, 25 miles northwest of Flagstaff. It rises {{convert|1,000|ft}} above the surroundings terrain and is shaped like the letter "U", with its opening towards the west. Geological Survey (USGS) and [[Organization:Northern Arizona University|Northern Arizona University]] scientists suggest that Red Mountain was formed in eruptions nearly 740,000 years ago.<ref name=USGS>{{cite web |url=http://pubs.usgs.gov/fs/2002/fs024-02/ |author1=Priest, Susan S.|author2=Wendell A. Duffield |author3=Nancy R. Riggs |display-authors=0 |year=2002 |title=Red Mountain Volcano – A Spectacular and Unusual Cinder Cone in Northern Arizona |work=fact sheet 024-02 |publisher=United States Geological Survey}}</ref>

==Geology==
Red Mountain is a cinder cone in the [[Earth:San Francisco volcanic field|San Francisco volcanic field]] that is noted for its red color and U shape when viewed from above. The cone was erupted from a volcanic vent that now sits under the intact material that comprises the U shape of the mountain. Overall, the pattern of volcanism is not symmetric about the vent suggesting either that [[Earth:Lava|lava]] was erupted under conditions of a strong west to east wind or late stage lava flows emanating from the vent may have rafted material out to the east.  The origin of the large amphitheater that sits within the U is unclear. Predominate theories suggest it resulted from a [[Earth:Phreatic eruption|steam eruption]].<ref name=USGS/> This steam eruption may have resulted from the [[Physics:Superheating|superheating]] of rainfall on cinders that were still hot. The well cemented cinders that make up the walls of the U may also result from interaction with rainwater. Chemical reactions driven by heated rainwater would also explain the variations in the color of the cinders.<ref name=USGS/>

The trail into the amphitheater contains small black grains that are often mistaken for Apache's tears ([[Chemistry:Obsidian|obsidian]]). These grains are actually large crystals of [[Chemistry:Pyroxene|pyroxene]] and [[Chemistry:Amphibole|amphibole]].<ref name=USGS/>

== References ==
{{reflist}}

==External links==
* [http://www.fs.fed.us/r3/coconino/recreation/peaks/red-mtn-tr.shtml Red Mountain trail guide] at Coconino National Forest

[[Category:Dormant volcanoes]]

{{Sourceattribution|Red Mountain (Coconino County, Arizona)}}