The Franklin Mountains of Texas (Spanish: Sierras de los Mansos[1]) are a small range 23 miles (37 km) long, 3 miles (5 km) wide that extend from El Paso, Texas, north into New Mexico.[2] The Franklins were formed due to crustal extension related to the Cenozoic Rio Grande rift. 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, between 85 and 45 million years ago.
Franklin Mountains | |
---|---|
Highest point | |
Peak | North Franklin Peak |
Elevation | 7,192 ft (2,192 m) |
Coordinates | 31°54′10″N 106°29′36″W / 31.90278°N 106.49333°W |
Geography | |
Country | United States |
States |
|
Geology | |
Orogeny | Laramide orogeny |
Rock age | Cretaceous |
Rock type(s) | Sedimentary, Igneous |
The highest peak is North Franklin Peak at 7,192 feet (2,192 m). Much of the range is part of the Franklin Mountains State Park. The mountains are composed primarily of sedimentary rock 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 rocks,[3] the oldest in Texas.[2][4]
Gallery
edit-
View of the south end of Franklin Mountains from El Paso, showing the abrupt termination of the range, its westward dip slope and terraced bolson deposits on each side. (1908)[5]
-
North Franklin Peak, looking northeast from South Franklin Mountain
-
South and North Franklin mountains, shown left to right, El Paso, Texas, as seen from Fort Bliss. The Organ Mountains can be glimpsed to the north, in the right part of the image.
-
View of South Franklin Mountain (aka Mount Franklin) (29 March 2009)
-
Franklin Mountains with Northwest El Paso in the background
See also
editReferences
edit- ^ Miles, Robert W. (June 12, 2010). "Franklin Mountains". tshaonline.org. Retrieved March 29, 2020.
- ^ a b Van Hise, C. R.; Leith, C. K. (1909). Pre-Cambrian Geology of North America. United States Geological Survey, Bulletin. Vol. 360. pp. 746–748. doi:10.3133/b360. OCLC 271845.
- ^ "Franklin Mountains State Park : Interpretive Guide" (PDF). Texas State Parks. 2019. Precambrian rocks can be seen in the Tom Mays unit of the Franklin Mountains park.
- ^ Brooks, A. H. (1904). "The Geological Society of Washington". Science. NS. 19 (490): 794–796. doi:10.1126/science.19.490.794.
- ^ Richardson, G. B. (1909). El Paso folio, Texas. United States Geological Survey, Folios of the Geologic Atlas. Vol. 166. Figure 10. doi:10.3133/gf166. OCLC 2514134.
External links
edit- Franklin Mountains (Texas) from the Handbook of Texas Online