The Franklin Mountains of Texas

Texas

Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...

 are a small range (23 miles long, 3 miles (4.8 km) wide) that extend from El Paso, Texas

El Paso, Texas

El Paso, is a city in and the county seat of El Paso County, Texas, United States, and lies in far West Texas. In the 2010 census, the city had a population of 649,121. It is the sixth largest city in Texas and the 19th largest city in the United States...

 north into New Mexico

New Mexico

New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...

. The Franklins were formed due to crustal extension related to the Cenozoic

Cenozoic

The Cenozoic era is the current and most recent of the three Phanerozoic geological eras and covers the period from 65.5 mya to the present. The era began in the wake of the Cretaceous–Tertiary extinction event at the end of the Cretaceous that saw the demise of the last non-avian dinosaurs and...

 Rio Grande rift

Rio Grande Rift

The Rio Grande Rift is a north-trending continental rift zone. It separates the Colorado Plateau in the west from the interior of the North American craton on the east. The rift extends from central Colorado in the north to the state of Chihuahua, Mexico in the south. The rift zone consists of four...

. Although the present topography of the range and adjoining basins is controlled by extension during rifting in the last 10 million years, faults within the range also record deformation during the Laramide orogeny

Laramide orogeny

The Laramide orogeny was a period of mountain building in western North America, which started in the Late Cretaceous, 70 to 80 million years ago, and ended 35 to 55 million years ago. The exact duration and ages of beginning and end of the orogeny are in dispute, as is the cause. The Laramide...

, between 85 and 45 million years ago.

The highest peak is North Franklin Mountain

North Franklin Mountain

North Franklin Mountain is a mountain in the Franklin Mountains of El Paso, Texas, located in the Southwestern United States. North Franklin, at , is the highest point in El Paso, and the 27th-highest mountain in the state of...

 at 7192 feet (2,192 m). Much of the range is part of the Franklin Mountains State Park

Franklin Mountains State Park

Franklin Mountains State Park is a Texas state park in El Paso, Texas in the United States. It is at an elevation of . It is the largest urban park in the nation lying completely within city limits, covering...

. The mountains are composed primarily of sedimentary rock

Sedimentary rock

Sedimentary rock are types of rock that are formed by the deposition of material at the Earth's surface and within bodies of water. Sedimentation is the collective name for processes that cause mineral and/or organic particles to settle and accumulate or minerals to precipitate from a solution....

 with some igneous intrusions. Geologists refer to them as tilted-block fault mountains and in them can be found 1.25 billion-year-old Precambrian

Precambrian

The Precambrian is the name which describes the large span of time in Earth's history before the current Phanerozoic Eon, and is a Supereon divided into several eons of the geologic time scale...

 rocks, the oldest in Texas.

See also

• Trans-Pecos
  Trans-Pecos
  The term Trans-Pecos, as originally defined in 1887 by the Texas geologist Robert T. Hill, refers to the portion of Texas that lies west of the Pecos River. The term is considered synonymous with "Far West Texas", a subdivision of West Texas...
  
  
• Chihuahuan Desert
  Chihuahuan Desert
  The Chihuahuan Desert is a desert, and an ecoregion designation, that straddles the U.S.-Mexico border in the central and northern portions of the Mexican Plateau, bordered on the west by the extensive Sierra Madre Occidental range, and overlaying northern portions of the east range, the Sierra...
  
  
• Davis Mountains
  Davis Mountains
  The Davis Mountains are a range of mountains in West Texas, located near Fort Davis, after which they are named. They are a popular site for camping and hiking and the region includes Fort Davis National Historic Site and Davis Mountains State Park...
  
  
• Guadalupe Mountains
  Guadalupe Mountains National Park
  Guadalupe Mountains National Park is located in the Guadalupe Mountains of West Texas and contains Guadalupe Peak, the highest point in Texas at in elevation. It also contains El Capitan, long used as a landmark by people traveling along the old route later followed by the Butterfield Overland...
  
  
• McKittrick Canyon
  McKittrick Canyon
  McKittrick Canyon is a scenic canyon within the Guadalupe Mountains of West Texas. The steep towering walls of McKittrick Canyon protect a rich riparian oasis in the midst of the Chihuahuan Desert....
  
  
• El Paso, Texas
  El Paso
  El Paso, a city in the U.S. state of Texas, on the border with Mexico.El Paso may also refer to:-Geography:Colombia:* El Paso, CesarSpain:*El Paso, Santa Cruz de TenerifeUnited States:...