Where is llano estacado located

These intermittent streams have cut scenic canyons into the eastern escarpment, most notably Palo Duro Canyon.

Nearly all runoff on the Llano, however, accumulates in the thousands of ephemeral, freshwater playa lakes, which capture as much as two to three million acre-feet of water annually, although most of it soon evaporates. Several theories explain the origin of the name Llano Estacado, though none is universally accepted. At present, a favored theory is that "estacado" refers to the palisaded or stockaded appearance of the caprock in many places, especially the west-facing escarpment in New Mexico.

Hunt, Charles B. Natural Regions of the United States and Canada. San Francisco: W. Freeman and Company, Because of its difficult conditions, the Llano Estacado has an extremely low population density, as can be seen in the map.

Most of the area's population is localized in the principal cities of Amarillo , Lubbock , Midland and Odessa , Texas. The vast majority of the area is rural , covered by large ranches and irrigated farms.

The Llano Estacado is larger in area than New England. The southern extension of the High Plains, the region is some miles north to south and miles east to west. The roads are straight and meet mostly at right angles. Cotton is an essential crop with irrigation, but faces declining prices at times on the world market.

The Llano Estacado is sometimes humorously described as "85 percent sky and 15 percent grassland. For years, the Llano Estacado was isolated from the state government in Austin and the national leadership in Washington, D.

Mahon , Kent Hance , and Robert L. Duncan emerged to defend its interests. The area has a large number of churches per capita. Lubbock, known for a wide variety of denominations, also holds the distinction of being the most populous city on the High Plains from the Dakotas through Texas. Prohibition did not end on the Texas Plains in with repeal of the Eighteenth Amendment to the United States Constitution , but continued for years at the county level.

Even in , some forty Texas counties, most in the Llano Estacado, remain officially "dry" to the sale of alcohol. The Ogallala Group is a late Tertiary Pliocene sheet of sediments spread over the area east of the Rocky Mountains from Wyoming to Texas, rather recently in a geological sense, when the Colorado Plateau and Rocky Mountain regions were elevated from near sea level to about their current elevations.

The eroded sediments mainly earlier Tertiary rocks spread over the low plains to the east. The Ancestral Rocky Mountains had been formed much earlier, at the end of the Cretaceous and the beginning of the Tertiary eras, and had been worn down to near flatness before the late Tertiary uplift.

In the northern areas, the Ogallala was spread over earlier Tertiary and Cretaceous rocks. In the Llano Estacado, erosion had removed everything down to the Triassic , and even to the Permian redbeds. At the southern end, some Cretaceous limestone remained, however.

The Ogallala was laid down over all of this by lazy, sandy streams near sea level, which produced the flatness of its surface. Subsequently, the uplift in the west progressed to the east, raising and tilting the Ogallala surface to its present position, and changing the environment from depositional to erosional. Some major rivers, such as the Pecos and Canadian , incised their courses deeply as the region was elevated, while others, such as the Red , Brazos , and Colorado rivers, arose on the dip slope.

The erosion of these rivers has now defined the area of the Llano Estacado, separating it from its Rocky Mountain sources and from other parts of the High Plains.

Other areas of the Ogallala surface, or High Plains, have the same history. In Wyoming, it is still in contact with the mountains west of Cheyenne the "Gangplank" , but elsewhere it is separated from the mountains by valleys of Cretaceous and earlier rocks due to active erosion at these higher levels.

Only in the Llano Estacado area has the formation of the Caprock given rise to a prominent, distinctive, palisade-like escarpment, as well as to a remarkably flat surface. Further north, rivers such as the Platte , Arkansas , and Cimarron have sliced it into segments. Another distinctive characteristic is that the surrounding rocks are often red, as in Palo Duro Canyon , making a striking contrast with the light-colored rocks of the plateau.

In some other places, the erosional edge of the High Plains is marked by "breaks" or other abrupt changes of scenery, as in eastern Wyoming and western Nebraska. In these areas, the High Plains are usually sandy, rolling plains with normal, branching drainage, not flat surfaces without continuous streams. The "bedrock" of the plain is the indurated top of the Ogallala Group , a hard caliche layer called the Caprock. This was formed when surface drying caused mineral-laden water to rise by capillary action to the surface.

Evaporating, the minerals were left behind to cement the otherwise fairly loose sandy sediments of the Ogallala Group. Tributaries of the Red, Brazos and Colorado rivers carve away at the eastern escarpment, which separates the Llano Estacado from the Rolling Plains of Texas and Oklahoma. Click on a photo to see a high-resolution image.

If you use any of these photos in a publication, on a web site, or as part of any other project, please credit the USDA-Agricultural Research Service. These photos may not be used to infer or imply ARS endorsement of any product, company, or position. Menu Agricultural Research Service U. Search small Search. December 23, Grain silo in McAdoo, Texas. An old irrigation standpipe west of Shallowater, Hockley County, Texas.