TheSierra Ancha ("broad range" inSpanish, inWestern Apache:Dził Nteel - "Wide Flat Mountain") is amountain range inGila County, in centralArizona. It lies betweenRoosevelt Lake to the south, theTonto Basin to the west, Cherry Creek to the east, and Pleasant Valley to the north. The range is one of several, including theBradshaw Mountains,Mingus Mountain of theBlack Hills, and theMazatzal Mountains, which form atransitional zone between the lowlanddeserts of southern Arizona and theColorado Plateau of northeastern Arizona. The highest point in the range is Aztec Peak, at an elevation of 2345 m (7694 ft).
The Sierra Ancha is penetrated by few improved roads, and the range is cut by numerous deep, spectacularcanyons, particularly on its eastern flank. Little agricultural, commercial, or residential development has taken place, though in the pastasbestos mining was carried out at a mine between Asbestos and Zimmerman Points. Cattle ranching is still practiced in the area. Nearby communities include Roosevelt,Tonto Basin,Punkin Center, andYoung, Arizona. The Sierra Ancha lies completely within Arizona'sTonto National Forest.
TwoU.S. Wilderness Areas lie within the Sierra Ancha — theSalome Wilderness, encompassingSalome Creek and its canyon on the southern edge of the range, and theSierra Ancha Wilderness, protecting the high peaks and deep canyons of the eastern flank of the range. The range also includes the U.S. Forest Service's Sierra Ancha Experimental Forest, a tract on which research on the characteristics ofSouthwestern U.S.watersheds has been conducted.
The Sierra Ancha includes abundantarchaeological remains, especially in the form ofcliff dwellings in the rugged canyons opening eastward toward Cherry Creek. The identity of the American Indian builders of these structures remains uncertain, but the sites show characteristics of both theSalado andMogollon cultures.Tree-ring dating of roof beams from the sites suggests that construction began in about 1280 AD, and that the structures were abandoned by 1350 AD.
Prominent streams within the Sierra Ancha areWorkman Creek andSalome Creek. The classicSonoran Desert floristic community ofsaguaro,palo verde, andcreosote bush can be found in the southern foothills above Roosevelt Lake (650–1000 m / 2133–3281 ft), while in the range's middle elevations (1200–1800 m / 3937–5906 ft)oak scrub andjuniper predominate. Above 6000 feet (1829 m), the Sierra Ancha has extensive stands ofponderosa pine, withDouglas-fir on the highest, coolest slopes. The Sierra Ancha holds adisjunctive population of coastal woodfern,Dryopteris arguta,[1] which is typically found closer to the Pacific Ocean,[2] owing to the relatively humid climate of the upper elevations of the range.
| Climate data for Sierra Ancha, Arizona Altitude: 5,100 feet (1,550 m) | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Record high °F | 76 | 79 | 84 | 91 | 97 | 105 | 104 | 103 | 103 | 96 | 83 | 78 | 105 |
| Mean daily maximum °F | 53.0 | 56.7 | 61.6 | 69.9 | 78.1 | 88.5 | 91.5 | 89.0 | 85.2 | 75.0 | 62.9 | 54.9 | 72.2 |
| Mean daily minimum °F | 30.3 | 32.6 | 35.6 | 41.7 | 48.5 | 57.7 | 62.6 | 61.7 | 58.3 | 48.4 | 37.6 | 31.8 | 45.6 |
| Record low °F | 0 | 10 | 11 | 16 | 22 | 30 | 34 | 38 | 29 | 20 | 12 | 2 | 0 |
| Averageprecipitation inches | 3.29 | 2.57 | 2.78 | 1.24 | 0.53 | 0.45 | 2.95 | 3.46 | 2.10 | 1.96 | 1.90 | 3.29 | 26.52 |
| Average snowfall inches | 7.1 | 4.2 | 3.5 | 0.7 | 0.5 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.6 | 3.8 | 20.4 |
| Record high °C | 24 | 26 | 29 | 33 | 36 | 41 | 40 | 39 | 39 | 36 | 28 | 26 | 41 |
| Mean daily maximum °C | 11.7 | 13.7 | 16.4 | 21.1 | 25.6 | 31.4 | 33.1 | 31.7 | 29.6 | 23.9 | 17.2 | 12.7 | 22.3 |
| Mean daily minimum °C | −0.9 | 0.3 | 2.0 | 5.4 | 9.2 | 14.3 | 17.0 | 16.5 | 14.6 | 9.1 | 3.1 | −0.1 | 7.6 |
| Record low °C | −18 | −12 | −12 | −9 | −6 | −1 | 1 | 3 | −2 | −7 | −11 | −17 | −18 |
| Averageprecipitation mm | 84 | 65 | 71 | 31 | 13 | 11 | 75 | 88 | 53 | 50 | 48 | 84 | 673 |
| Average snowfall cm | 18 | 11 | 8.9 | 1.8 | 1.3 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 1.5 | 9.7 | 52.2 |
| Average precipitation days(≥ 0.01 in) | 7 | 6 | 6 | 3 | 2 | 2 | 9 | 10 | 6 | 4 | 4 | 6 | 65 |
| Source: WRCC[3] | |||||||||||||
The Sierra Ancha features significant exposures of theApache Group, a complex consisting ofProterozoicconglomerate,shale, dolomiticlimestone, andquartzite, with large-scaleintrusions ofdiabase. The purplishDripping Spring Quartzite and white-pinkish Troy Quartzite are much more resistant toweathering than the surroundingstrata and form the Sierra Ancha's spectacular cliffs. In lower Parker Canyon, on the range's south face, the Dripping Springs Quartzite forms precipices with a 200 m (700 ft) vertical drop. The light-colored cliffs topping upper Parker Canyon have been formed from the Troy Quartzite. Thebasement (lowest) rock throughout the range consists of the Proterozoic RuinGranite. The top of Aztec Peak is capped with a coarse-grained, brown,Cambriansandstone analogous to theTapeats Sandstone of theGrand Canyon. The Tapeats Sandstone lies on anunconformity at 850 m (2,790 ft) in the Grand Canyon, whereas at Aztec Peak it appears at about 2,350 m (7,710 ft), a vertical displacement from which can be inferred about 1,500 m (4,900 ft) of ancientuplift, implying that the Sierra Ancha once stood at least 1500 m higher than the range does today, and that thePaleozoic strata which overlie the Tapeats in the Grand Canyon have been removed in the Sierra Ancha througherosion. Gravels consistent with erosional removal and deposition can be found on top of theColorado Plateau to the north of the Sierra Ancha.[4]
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33°57′27″N111°11′12″W / 33.95750°N 111.18667°W /33.95750; -111.18667
