The Sweetwater Mountains (highest peak: Mount Patterson ) are a small

mountain range A mountain range or hill range is a series of mountains or hills arranged in a line and connected by high ground. A mountain system or mountain belt is a group of mountain ranges with similarity in form, structure, and alignment that have aris ...

in northern

Mono County Mono County ( ) is a county located in the east central portion of the U.S. state of California. As of the 2020 United States census, the population was 13,195, making it the fourth-least populous county in California. The county seat is Bridg ...

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

and western Lyon County,

Nevada Nevada ( ; ) is a landlocked state in the Western United States. It borders Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the seventh-most extensive, th ...

, separating the

West Walker River The West Walker River is a tributary of the Walker River, approximately long,U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map accessed March 17, 2011 in eastern California and western Nevada in ...

from the

East Walker River The East Walker River is an approximately long,U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map , accessed March 17, 2011 tributary of the Walker River, in eastern California and western Nevada ...

. Most of the range is only accessible by

four wheel drive The Four Wheel Drive Auto Company, more often known as Four Wheel Drive (FWD), was a pioneering American company that developed and produced all-wheel drive vehicles. It was founded in 1909 in Clintonville, Wisconsin, as the Badger Four-Wheel Dr ...

vehicle, on foot, or

pack animal A pack animal, also known as a sumpter animal or beast of burden, is a working animal used to transport goods or materials by carrying them, usually on its back. Domestic animals of many species are used in this way, among them alpacas, Bact ...

. Most of the range is contained in the Toiyabe National Forest. The place name appears on the 1874 California Geologic Survey map of California and Nevada. The ghost towns of Belfort and Clinton are small gold mining camps on the southeastern slope of Mt. Patterson. The Sweetwater post office existed on the eastern boundary of the range in the 1920s. The Fales post office existed on the southwestern boundary in 1877. Both Clinton and Belfort had post offices in the 1880s. There are several other inactive small gold mining camps and gold mines in the range, including Boulder Flat, Montague Mine, Angelo Mission Mine, Kentuck Mine, Frederick Mine, Longstreet Mine, Lilly Mine, Deep Creek Mine, and Tiger Mine. The area roughly forming a SE quadrant from the summit of Mt Patterson, bounded by Sweetwater Canyon (easterly line) and Frying Pan Canyon (southerly line), is known as the Patterson Mining District of Mono County according to the 1888 report of the State of California Mineralogist. The 1888 report also records the Cameron mining camp, which is now unknown. At least one mining company issued stock: Monte Cristo Consolidated Mining Company, 100,000 shares issued in 1887 at $10 each. The Sweetwater Mountains geology largely consists of a

pluton In geology, an igneous intrusion (or intrusive body or simply intrusion) is a body of intrusive igneous rock that forms by crystallization of magma slowly cooling below the surface of the Earth. Intrusions have a wide variety of forms and com ...

surrounded by

volcanic A volcano is commonly defined as a vent or fissure in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often fo ...

flow from the Little Walker Caldera. Mt. Patterson is a volcano of uncertain age which is capped with white

rhyolite Rhyolite ( ) is the most silica-rich of volcanic rocks. It is generally glassy or fine-grained (aphanitic) in texture (geology), texture, but may be porphyritic, containing larger mineral crystals (phenocrysts) in an otherwise fine-grained matri ...

. Besides Mount Patterson, other peaks in the Sweetwater Range include Middle Sister and East Sister.

References

Mountain ranges of Nevada Mountain ranges of Northern California Mountain ranges of Mono County, California Mountain ranges of Lyon County, Nevada {{MonoCountyCA-geo-stub