In geology, a fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within the Earth's crust result from the action of plate tectonic forces, with the largest forming the boundaries between the plates, such as subduction zones or transform faults. Energy release associated with rapid movement on active faults is the cause of most earthquakes. Faults may also displace slowly, by aseismic creep.
The Funeral Mountains are a short, arid mountain range in the United States along the California-Nevada border approximately 100 mi (160 km) west of Las Vegas. The mountains are considered a subrange of the Amargosa Range that form the eastern wall of Death Valley.
The Chino Hills are a mountain range on the border of Orange, Los Angeles, and San Bernardino counties, California, with a small portion in Riverside County. The Chino Hills State Park preserves open space and habitat in them.
The Virginia Mountains is an irregular mountain range entirely in Washoe County, Nevada, that generally extends north-northwest to south-southeast for 22 miles (35 km).
The La Posa Plain is a wide, generally flat plain in western Arizona near the Colorado River and is on the west and northwest border of the Kofa National Wildlife Refuge. The plain lies to the east of the Colorado River Indian Reservation and east of the Dome Rock and Trigo Mountains. Quartzsite, Arizona, lies on the western part of the plain, which crosses both Interstate 10 and U.S. Route 95.
The Tinajas Altas Mountains are an extremely arid northwest-southeast trending mountain range in southern Yuma County, Arizona, approximately 35 mi southeast of Yuma, Arizona. The southern end of the range extends approximately one mile into the northwestern Mexican state of Sonora on the northern perimeter of the Gran Desierto de Altar. The range is about 22 mi in length and about 4 mi wide at its widest point. The highpoint of the range is unnamed and is 2,766 feet above sea level and is located at 32°16'26"N, 114°02'48"W. Aside from the portion of the range in Mexico, the entirety of the range lies within the Barry M. Goldwater Air Force Range. They lie at the heart of the traditional homeland of the Hia C-eḍ O'odham people.
The New Water Mountains is a mountain range in southwestern Arizona. The range is on the northern border of the Kofa National Wildlife Refuge as well as the northern Kofa Mountains.
The Muggins Mountains is a mountain range in southwest Arizona east of Yuma, Arizona, northeast of the Gila Mountains, and east of the Laguna Mountains. The Castle Dome Mountains lie to the northeast across the broad Castle Dome Plain. The Muggins Mountains Wilderness occupies the southwest portion of the range.
The Tank Mountains are a mountain range in the Sonoran Desert of southwest Arizona; the range is part of the southeastern border of the Kofa National Wildlife Refuge.
The Bryan Mountains are a small mountain range in the northwestern Sonoran Desert of southwestern Arizona. The range is located in southeastern Yuma County, about 75 mi southeast of Yuma and about 35 mi west of Ajo. The range is approximately ten miles long and about three miles wide at its widest point. The highpoint of the range is 1,794 feet above sea level and is located at 32°18'27"N, 113°22'46"W. The range is located entirely within the Cabeza Prieta National Wildlife Refuge.
The Little Ajo Mountains is a mountain range in southern Arizona, in extreme western Pima County, Arizona. The city of Ajo sits on the northeast of this small mountain range. Both the mountain range and city take their name from the Spanish word for garlic.
The Bullfrog Hills are a small mountain range of the Mojave Desert in southern Nye County, southwestern Nevada. Bullfrog Hills was so named from a fancied resemblance of its ore to the color of a bullfrog.
The Arica Mountains are a small mountain range in northern Riverside County, California. The range lies along the south edge of Rice Valley 6.2 miles (10.0 km) southwest of the old Rice townsite on California State Route 62. They lie 6 miles (9.7 km) north of the Little Maria Mountains and 9 miles (14 km) southwest of the Turtle Mountains. The Granite Mountains lie about 8 miles to the west. They are in the Colorado Desert, in the Lower Colorado River Valley region. They are north the Palen Mountains and Big Maria Mountains; and northwest of Blythe, California.
The Coyote Mountains are a small mountain range in San Diego and Imperial Counties in southern California. The Coyotes form a narrow ESE trending 2 mi (3.2 km) wide range with a length of about 12 mi (19 km). The southeast end turns and forms a 2 mi (3.2 km) north trending "hook". The highest point is Carrizo Mountain on the northeast end with an elevation of 2,408 feet (734 m). Mine Peak at the northwest end of the range has an elevation of 1,850 ft (560 m). Coyote Wash along I-8 along the southeast margin of the range is 100 to 300 feet in elevation. Plaster City lies in the Yuha Desert about 5.5 mi (8.9 km) east of the east end of the range.
The San Luis Mountains are a small, lower elevation mountain range of central-southern Pima County Arizona adjacent to the U.S.-Mexico border, northeast of Sasabe, Arizona–Sasabe, Sonora.
The Harcuvar Mountains are a narrow mountain range in western-central Arizona, USA. The range lies just east of the north-south Colorado River, and south of the east-west, west-flowing Bill Williams River, from Alamo Lake.
The Buckskin Mountains is a mountain range in La Paz County, Arizona, United States. The range lies just east of the north-south Colorado River, and borders south of the east-west, west-flowing Bill Williams River.
The Black Hills of Yavapai County are a large mountain range of central Arizona in southeast Yavapai County. It is bordered by the Verde Valley to the east. The northwest section of the range is bisected from the southeast section by Interstate 17, which is the main route connecting Phoenix to Sedona, Oak Creek Canyon, and Flagstaff. This bisection point is the approximate center of the mostly northwest by southeast trending range. The northwest section contains a steep escarpment on the northeast with the Verde Valley, the escarpment being the location of the fault-block that created the historic mining district at Jerome. The United Verde Mine was one of the largest copper mines in the United States, producing large quantities of copper, gold, silver and zinc.
The West Silver Bell Mountains are a small 10 mile (16 km) long mountain range of south-central Arizona, United States. The range lies in the north-central arid Sonoran Desert; the Madrean Sky Islands region of southeast Arizona, around Tucson is adjacent to the southeast.
The Poachie Range is a moderate length mountain range and massif in southeast Mohave County, Arizona, and the extreme southwest corner of Yavapai County; the range also abuts the northeast corner of La Paz County. The Poachie Range massif is bordered by the south-flowing Big Sandy River on its west, and the west-flowing Santa Maria River on its south; both rivers converge at the Poachie Range's southwest at Alamo Lake, the Alamo Lake State Park.
