Geography of Texas

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A physical map of Texas Relief map of Texas.png
A physical map of Texas
Geographic map of Texas Texas topographic map-en.svg
Geographic map of Texas
Koppen climate classification types of Texas Texas Koppen.svg
Köppen climate classification types of Texas

The geography of Texas is diverse and large. Occupying about 7% of the total water and land area of the U.S., [1] it is the second largest state after Alaska, and is the southernmost part of the Great Plains, which end in the south against the folded Sierra Madre Oriental of Mexico. Texas is in the south-central part of the United States of America, and is considered to form part of the U.S. South and also part of the U.S. Southwest. [2]

Alaska State of the United States of America

Alaska is a U.S. state in the northwest extremity of North America, just across the Bering Strait from Asia. The Canadian province of British Columbia and territory of Yukon border the state to the east and southeast. Its most extreme western part is Attu Island, and it has a maritime border with Russia to the west across the Bering Strait. To the north are the Chukchi and Beaufort seas—southern parts of the Arctic Ocean. The Pacific Ocean lies to the south and southwest. It is the largest U.S. state by area and the seventh largest subnational division in the world. In addition, it is the 3rd least populous and the most sparsely populated of the 50 United States; nevertheless, it is by far the most populous territory located mostly north of the 60th parallel in North America: its population—estimated at 738,432 by the United States Census Bureau in 2015— is more than quadruple the combined populations of Northern Canada and Greenland. Approximately half of Alaska's residents live within the Anchorage metropolitan area. Alaska's economy is dominated by the fishing, natural gas, and oil industries, resources which it has in abundance. Military bases and tourism are also a significant part of the economy.

Great Plains broad expanse of flat land west of the Mississippi River and east of the Rocky Mountains in the United States and Canada

The Great Plains is the broad expanse of flat land, much of it covered in prairie, steppe, and grassland, that lies west of the Mississippi River tallgrass prairie in the United States and east of the Rocky Mountains in the U.S. and Canada. It embraces:

Sierra Madre Oriental mountain range in Mexico

The Sierra Madre Oriental is a mountain range in northeastern Mexico. The Sierra Madre Oriental is part of the American Cordillera, a chain of mountain ranges (cordillera) that consists of an almost continuous sequence of mountain ranges that form the western "backbone" of North America, Central America, South America and Antarctica.

Contents

By residents, the state is generally divided into North Texas, East Texas, Central Texas, South Texas, West Texas (and sometimes the Panhandle), but according to the Texas Almanac , Texas has four major physical regions: Gulf Coastal Plains, Interior Lowlands, Great Plains, and Basin and Range Province. This has been cited as the difference between human geography and physical geography, although the fact that Texas was granted the prerogative to divide into as many as five U.S. states may be a historical motive for Texans defining their state as containing exactly five regions. [3]

North Texas

North Texas is a term used primarily by residents of Dallas, Fort Worth, and surrounding areas to describe much of the northern portion of the U.S. state of Texas. Residents of the Dallas–Fort Worth Metroplex generally consider North Texas to include the area south of Oklahoma, east of Abilene, west of Paris, and north of Waco. A more precise term for this region would be the northern part of the central portion of Texas. It does not include the Panhandle of Texas, which expands further north than the region previously described, nor does it include most of the region near the northern border of Texas.

East Texas cultural, geographic and ecological area in the US federated state of Texas

East Texas is a distinct cultural, geographic and ecological area in the U.S. state of Texas.

Central Texas geographic region

Central Texas is a region in the U.S. state of Texas surrounding Austin and roughly bordered by Brady to Brenham to Seguin to Waco. Central Texas contains the Texas Hill Country and corresponds to a physiographic section designation within the Edwards Plateau, in a geographic context.

Some regions in Texas [4] are more associated with the Southeast than the Southwest (primarily East Texas, Central Texas, and North Texas), while other regions share more similarities with the Southwest (primarily far West Texas and South Texas). The upper Panhandle is considered by many to have more in common with parts of the plains Midwest than either the South or Southwest. The size of Texas prohibits easy categorization of the entire state wholly in any recognized region of the United States, and even cultural diversity among regions of the state make it difficult to treat Texas as a region in its own right.

West Texas Region in Texas, United States

West Texas is a loosely defined part of the U.S. state of Texas, generally encompassing the arid and semiarid lands west of a line drawn between the cities of Wichita Falls, Abilene, and Del Rio.

South Texas region of the U.S. state of Texas

South Texas is a region of the U.S. state of Texas that lies roughly south of—and sometimes including—San Antonio. The southern and western boundary is the Rio Grande, and to the east it is the Gulf of Mexico. The population of this region is about 4.96 million according to the 2017 census estimates. The southern portion of this region is often referred to as the Rio Grande Valley. The eastern portion along the Gulf of Mexico is also referred to as the Coastal Bend.

Salient (geography)

A salient is an elongated protrusion of a geopolitical entity, such as a subnational entity or a sovereign state.

Climate

Texas rivers map showing Captain Marcy's route though Texas in 1854. Texas Rivers 1895.jpg
Texas rivers map showing Captain Marcy's route though Texas in 1854.

Continental, Mountain, and Modified Marine are the three major climatic types of Texas, with no distinguishable boundaries. Modified Marine, or subtropical, dominates the majority of the state. [5] Texas has an annual precipitation range from 60.57 inches (1,538 mm) in Jasper County, East Texas, to 9.43 inches (240 mm) in El Paso. The record high of 120  °F (49  °C ) was reached at Seymour on August 12, 1936, and Monahans on June 28, 1994. The low also ties at −23  °F (−31  °C ) in Tulia on February 12, 1899, and Seminole on February 8, 1933. [6]

Continental climate

Continental climates often have a significant annual variation in temperature. They tend to occur in the middle latitudes, where prevailing winds blow overland, and temperatures are not moderated by bodies of water such as oceans or seas. Continental climates occur mostly in the Northern Hemisphere, which has the kind of large landmasses on temperate latitudes required for this type of climate to develop. Most of northern and northeastern China, eastern and southeastern Europe, central and southeastern Canada, and the central and upper eastern United States have this type of climate.

Subtropics

The subtropics are geographic and climate zones located roughly between the tropics at latitude 23.5° and temperate zones north and south of the Equator.

Climate Statistics of weather conditions in a given region over long periods

Climate is the statistics of weather over long periods of time. It is measured by assessing the patterns of variation in temperature, humidity, atmospheric pressure, wind, precipitation, atmospheric particle count and other meteorological variables in a given region over long periods of time. Climate differs from weather, in that weather only describes the short-term conditions of these variables in a given region.

Physical geography

Texas covers a total area of 268,581 square miles (695,622 km2). The longest straight-line distance is from the northwest corner of the panhandle to the Rio Grande river just below Brownsville, 801 miles (1,289 km). [1] The width west-to-east, from El Paso to Orange, Texas, is 762 miles (1,226 km). The largest continental state is so expansive that El Paso, in the western corner of the state, is closer to San Diego, California, than to the Houston and Beaumont area, near the Louisiana state line; while Orange, on the border to Louisiana, is closer to Jacksonville, Florida than it is to El Paso. Texarkana, in the northeastern corner of the state, is about the same distance from Chicago, Illinois, as it is to El Paso, and Dalhart, in the northwestern corner of the state, is closer to the state capitals of Kansas, Nebraska, Colorado, New Mexico, Oklahoma and Wyoming than it is to Austin, its own state capital. [7]

Rio Grande river forming part of the US-Mexico border

The Rio Grande is one of the principal rivers in the southwest United States and northern Mexico. The Rio Grande begins in south-central Colorado in the United States and flows to the Gulf of Mexico. Along the way, it forms part of the Mexico–United States border. According to the International Boundary and Water Commission, its total length was 1,896 miles (3,051 km) in the late 1980s, though course shifts occasionally result in length changes. Depending on how it is measured, the Rio Grande is either the fourth- or fifth-longest river system in North America.

Brownsville, Texas City in Texas, United States

Brownsville is a city in Cameron County in the U.S. state of Texas. It located on the western Gulf Coast in South Texas, adjacent to the border with Matamoros, Mexico. The city covers 81.528 square miles (211.157 km2) and has a population of 183,299 as of 2017. It is the 131st-largest city in the United States and 16th-largest in Texas. It is part of the Brownsville–Matamoros conurbation, with a population of 1,136,995 people. The city is known for its year-round subtropical climate, deep-water seaport and Hispanic culture.

El Paso, Texas City in Texas, United States

El Paso is a city in and the county seat of El Paso County, Texas, United States, in the far western part of the state. The 2017 population estimate for the city from the U.S. Census was 683,577. Its metropolitan statistical area (MSA) covers all of El Paso and Hudspeth counties in Texas, and has a population of 844,818.

The geographic center of Texas is about 15 miles (24 km) northeast of Brady in northern McCulloch County. Guadalupe Peak, at 8,749 feet (2,666.7 m) above sea level, is the highest point in Texas, the lowest being sea level where Texas meets the Gulf of Mexico. [8] Texas has five state forests and 120 state parks for a total over 605,000 acres (2,450 km2). [9] There are 3,700 named streams and 15 major river systems flowing through 191,000 miles (307,000 km) of Texas. Eventually emptying into seven major estuaries, these rivers support over 212 reservoirs. [10]

Brady, Texas City in Texas, United States

Brady is a city in McCulloch County, Texas, United States. Brady refers to itself as "The Heart of Texas", as it is the closest city to the geographical center of the state, which is about 15 miles northeast of Brady. The population was 5,528 at the 2010 census. It is the county seat of McCulloch County.

McCulloch County, Texas County in the United States

McCulloch County is a county located on the Edwards Plateau in the U.S. state of Texas. At the 2010 census, its population was 8,283. Its county seat is Brady. The county was created in 1856 and later organized in 1876. It is named for Benjamin McCulloch, a famous Texas Ranger and Confederate general.

Guadalupe Peak Highest mountain peak in Texas

Guadalupe Peak, also known as Signal Peak, is the highest natural point in Texas, with an elevation of 8,751 feet (2,667 m) above sea level. It is located in Guadalupe Mountains National Park, and is part of the Guadalupe Mountains range in southeastern New Mexico and West Texas. The mountain is about 90 miles (140 km) east of El Paso and about 50 miles (80 km) southwest of Carlsbad, New Mexico. The peak rises more than 3,000 feet (910 m) above the arid floor of the Chihuahuan Desert.

With 10 climatic regions, 14 soil regions, and 11 distinct ecological regions, regional classification becomes problematic with differences in soils, topography, geology, rainfall, and plant and animal communities. [11]

Coastal Plains

Caddo Lake Caddo Lake- Cypress.jpg
Caddo Lake

The Gulf Coastal Plains extends from the Gulf of Mexico inland to the Balcones Fault and the Eastern Cross Timbers. This large area, including the Texas barrier islands, stretches from the cities of Paris to San Antonio to Del Rio but shows a large variety in vegetation. With about 20 to over 58 inches (508–1,480 mm) annual rainfall, this is a nearly level, drained plain dissected by streams and rivers flowing into estuaries and marshes. Windblown sands and dunes, grasslands, oak mottes and salt marshes make up the seaward areas. [12] National Parks include Big Thicket National Preserve, Padre Island National Seashore and the Palo Alto Battlefield National Historic Site. [13]

North Central Plains

Looking north at the Caprock Escarpment. Caprock Escarpment.jpg
Looking north at the Caprock Escarpment.

The North Central Plains are bounded by the Caprock Escarpment to the west, the Edwards Plateau to the south, and the Eastern Cross Timbers to the east. This area includes the North Central Plains around the cities of Abilene and Wichita Falls, the Western Cross Timbers to the west of Fort Worth, the Grand Prairie, and the Eastern Cross Timbers to the east of Dallas. With about 35 to 50 inches (890 to 1,270 mm) annual rainfall, gently rolling to hilly forested land is part of a larger pine-hardwood forest of oaks, hickories, elm and gum trees. [12] Soils vary from coarse sands to tight clays or shet rock clays and shales. [14]

Great Plains

Hill Country Texas Hill Country Near I-10, 2004.jpg
Hill Country

The Great Plains include the Llano Estacado, the Panhandle, Edwards Plateau, Toyah Basin, and the Llano Uplift. It is bordered on the east by the Caprock Escarpment in the panhandle and by the Balcones Fault to the southeast. Cities in this region include Midland and Odessa, Lubbock, and Amarillo. The Hill Country is a popular name for the area of hills along the Balcones Escarpment and is a transitional area between the Great Plains and the Gulf Coastal Plains. With about 15 to 31 inches (380 to 790 mm) annual rainfall, the southern end of the Great Plains are gently rolling plains of shrub and grassland, and home to the dramatic Caprock Canyons and Palo Duro Canyon state parks. [12] The largest concentration of playa lakes in the world (nearly 22,000) is on the Southern High Plains of Texas and Eastern New Mexico.

Texas' blackland prairies were some of the first areas farmed in Texas. Highly expansive clays with characteristic dark coloration, called the Houston Black series, occur on about 1.5 million acres (6,000 km²) extending from north of Dallas south to San Antonio. The Professional Soil Scientists Association of Texas has recommended to the State Legislature that the Houston Black series be designated the State soil. The series was established in 1902. [15] National Parks in this area are the Lyndon B. Johnson National Historical Park and the San Antonio Missions National Historical Park. [13]

Mountains and basins

Rio Grande Valley in the Big Bend area Big Bend Rio Grande.jpg
Rio Grande Valley in the Big Bend area
El Capitan El Capitan base 2005-03-12.jpg
El Capitan

The Trans-Pecos Natural Region has less than 12 inches (300 mm) annual rainfall. The most complex Natural Region, it includes Sand Hills, the Stockton Plateau, desert valleys, wooded mountain slopes and desert grasslands. The Basin and Range Province is in West Texas, west of the Pecos River, beginning with the Davis Mountains on the east and the Rio Grande to its west and south. The Trans-Pecos region is the only part of Texas regarded as mountainous and includes seven named peaks in elevation greater than 8,000 feet (2,400 m). This region includes sand hills, desert valleys, wooded mountain slopes and desert grasslands. [12] The vegetation diversity includes at least 268 grass species and 447 species of woody plants. [16] National Parks include the Amistad National Recreation Area, Big Bend National Park, Chamizal National Memorial, Fort Davis National Historic Site, Guadalupe Mountains National Park, and the Rio Grande Wild and Scenic River. [13] This area is part of the Chihuahuan Desert.

Geology

Texas is mostly sedimentary rocks, with East Texas underlain by a Cretaceous and younger sequence of sediments, the trace of ancient shorelines east and south until the active continental margin of the Gulf of Mexico is met. This sequence is built atop the subsided crest of the Appalachian Mountains Ouachita Mountains Marathon Mountains zone of Pennsylvanian continental collision, which collapsed when rifting in Jurassic time opened the Gulf of Mexico. West from this orogenic crest, which is buried beneath the Dallas Waco Austin San Antonio trend, the sediments are Permian and Triassic in age. Oil is found in the Cretaceous sediments in the east, the Permian sediments in the west, and along the Gulf coast and out on the Texas continental shelf. A few exposures of Precambrian igneous and metamorphic rocks are found in the central and western parts of the state, and Oligocene volcanic rocks are found in far west Texas, in the Big Bend area. A blanket of Miocene sediments known as the Ogallala formation in the western high plains region is an important aquifer. Texas has no active or dormant volcanoes and few earthquakes, being situated far from an active plate tectonic boundary. The Big Bend area is the most seismically active; however, the area is sparsely populated and suffers minimal damages and injuries, and no known fatalities have been attributed to a Texas earthquake.

Resources

With a large supply of natural resources, Texas is a major agricultural and industrial state, producing oil, cattle, sheep, and cotton. The state also produces poultry, eggs, dairy products, greenhouse and nursery products, wheat, hay, rice, sugar cane, and peanuts, and a range of fruits and vegetables. [17]

Shaded Relief Map of the Llano Estacado. LlanoEstacadoShadedRelief.jpg
Shaded Relief Map of the Llano Estacado.

Related Research Articles

Permian Basin (North America)

The Permian Basin is a large sedimentary basin in the southwestern part of the United States. The basin contains the Mid-Continent Oil Field province. This sedimentary basin is located in western Texas and southeastern New Mexico. It reaches from just south of Lubbock, past Midland and Odessa, south nearly to the Rio Grande River in southern West Central Texas, and extending westward into the southeastern part of New Mexico. It is so named because it has one of the world's thickest deposits of rocks from the Permian geologic period. The greater Permian Basin comprises several component basins; of these, the Midland Basin is the largest, Delaware Basin is the second largest, and Marfa Basin is the smallest. The Permian Basin covers more than 86,000 square miles (220,000 km2), and extends across an area approximately 250 miles (400 km) wide and 300 miles (480 km) long.

Texas Panhandle Region in Texas, United States

The Texas Panhandle is a region of the U.S. state of Texas consisting of the northernmost 26 counties in the state. The panhandle is a rectangular area bordered by New Mexico to the west and Oklahoma to the north and east. The Handbook of Texas defines the southern border of Swisher County as the southern boundary of the Texas Panhandle region.

Llano Uplift

The Llano uplift is a low geologic dome that is about 90 miles (140 km) in diameter. It consists of an island-like exposure of Precambrian igneous and metamorphic rocks surrounded by outcrops of Paleozoic and Cretaceous sedimentary strata. At their widest, the exposed Precambrian rocks extend about 65 miles (105 km) westward from the valley of the Colorado River and beneath a broad, gentle topographic basin drained by the Llano River. The subdued topographic basin is underlain by Precambrian rocks and bordered by a discontinuous rim of flat-topped hills. These hills are the dissected edge of the Edwards Plateau, which consist of overlying Cretaceous sedimentary strata. Within this basin and along its margin are down-faulted blocks and erosional remnants of Paleozoic strata which form prominent hills.

Llano Estacado Southwestern United States in New Mexico

Llano Estacado, often translated as Staked Plains, is a region in the Southwestern United States that encompasses parts of eastern New Mexico and northwestern Texas. One of the largest mesas or tablelands on the North American continent, the elevation rises from 3,000 feet (900 m) in the southeast to over 5,000 feet (1,500 m) in the northwest, sloping almost uniformly at about 10 feet per mile (1.9 m/km).

South Plains Region in Texas, United States

The South Plains is region in northwest Texas, consisting of 24 counties. The main crop is cotton.

Alleghanian orogeny

The Alleghanian orogeny or Appalachian orogeny is one of the geological mountain-forming events that formed the Appalachian Mountains and Allegheny Mountains. The term and spelling Alleghany orogeny was originally proposed by H.P. Woodward in 1957.

Geology of Texas

Texas contains a great variety of geologic settings. The state's stratigraphy has been largely influenced by marine transgressive-regressive cycles during the Phanerozoic, with a lesser but still significant contribution from late Cenozoic tectonic activity, as well as the remnants of a Paleozoic mountain range.

Trans-Pecos

The Trans-Pecos, as originally defined in 1887 by the Texas geologist Robert T. Hill, is 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. The Trans-Pecos is part of the Chihuahuan Desert, the largest desert in North America. It is the most mountainous and arid portion of the state, and most of its area is vast and sparsely populated, comprising seven of the ten largest counties by area in Texas. The area is known for the natural environment of the Big Bend and the gorge of the Rio Grande, part of which has been designated a National Wild and Scenic Rivers System. With the notable exceptions of Big Bend Ranch State Park, Big Bend National Park and the Guadalupe Mountains National Park, the vast majority of the Trans-Pecos region consists of privately owned ranchland. However, the majority of the region's population reside in the El Paso metropolitan area.

Caprock Escarpment

The Caprock Escarpment is a term used in West Texas and Eastern New Mexico to describe the geographical transition point between the level high plains of the Llano Estacado and the surrounding rolling terrain. In Texas, the escarpment stretches around 200 mi (320 km) south-southwest from the northeast corner of the Texas Panhandle near the Oklahoma border. The escarpment is especially notable, from north to south, in Briscoe, Floyd, Motley, Crosby, Dickens, Garza, and Borden Counties. In New Mexico, a prominent escarpment exists along the northernmost extension of the Llano Estacado, especially to the south of San Jon and Tucumcari, both in Quay County, New Mexico. Along the western edge of the Llano Estacado, the portion of the escarpment that stretches from Caprock to Maljamar, New Mexico is called the Mescalero Ridge.

Eastern New Mexico Region in New Mexico, United States

Eastern New Mexico is a physiographic subregion within the U.S. state of New Mexico. The region is sometimes called the "High Plains," "Eastern Plains ," or even "Little Texas". The region is largely coterminous with the portion of the Llano Estacado in New Mexico. Eastern New Mexico mostly lies upon the high plains, which extends to elevations over 4,000 ft (1,200 m). The region is mostly characterized by flat featureless terrain with the exception of the Pecos River valley and the abrupt breaks along the Mescalero Ridge and northern caprock escarpments of the Llano Estacado. The region typically lacks the high relief of central and northern New Mexico, such as that in the Sangre de Cristo and Sandia mountain ranges.

Solitario mountain in Texas, United States of America

The Solitario is a large geologic formation in Big Bend Ranch State Park in West Texas. When viewed from above, it suggests an impact crater; though it is actually the eroded remains of a laccolith. The approximate center of the Solitario is located 56.8 km (35.3 mi) east southeast of Presidio, Texas, just west of the line dividing Brewster County, Texas and Presidio County, Texas. The formation covers a circular area of approximately 135 km2 (52 sq mi). The geology of the Solitario is complex. In 1988 the state of Texas purchased the property containing the Solitario and created Big Bend Ranch State Park.

Climate of Texas

Texas' weather varies widely, from arid in the west to humid in the east. The huge expanse of Texas encompasses several regions with distinctly different climates: Northern Plains, Trans-Pecos Region, Texas Hill Country, Piney Woods, and South Texas. Generally speaking, the part of Texas that lies to the east of Interstate 35 is subtropical, while the portion that lies to the west of Interstate 35 is arid desert.

Geology of Kansas

The Geology of Kansas encompasses the geologic history of the US state of Kansas and the present-day rock and soil that is exposed there. Rock that crops out in Kansas was formed during the Phanerozoic eon, which consists of three geologic eras: the Paleozoic, Mesozoic and Cenozoic. Paleozoic rocks at the surface in Kansas are primarily from the Mississippian, Pennsylvanian and Permian periods.

Geology of Queensland

The geology of Queensland can be subdivided into several regions with different histories. Along the east coast is a complex of Palaezoic to Cainozoic rocks while much of the rest of the state is covered by Cretaceous and Cainozoic rocks. A Precambrian basement is found in the north west and Cape York regions. The Thomson Orogen occurs in the central and southern parts of Queensland, but is mostly covered by younger basins.

Paleontology in Texas

Paleontology in Texas refers to paleontological research occurring within or conducted by people from the U.S. state of Texas. Author Marian Murray has remarked that "Texas is as big for fossils as it is for everything else." Some of the most important fossil finds in United States history have come from Texas. Fossils can be found throughout most of the state. The fossil record of Texas spans almost the entire geologic column from Precambrian to Pleistocene. Shark teeth are probably the state's most common fossil. During the early Paleozoic era Texas was covered by a sea that would later be home to creatures like brachiopods, cephalopods, graptolites, and trilobites. Little is known about the state's Devonian and early Carboniferous life. However, evidence indicates that during the late Carboniferous the state was home to marine life, land plants and early reptiles. During the Permian, the seas largely shrank away, but nevertheless coral reefs formed in the state. The rest of Texas was a coastal plain inhabited by early relatives of mammals like Dimetrodon and Edaphosaurus. During the Triassic, a great river system formed in the state that was inhabited by crocodile-like phytosaurs. Little is known about Jurassic Texas, but there are fossil aquatic invertebrates of this age like ammonites in the state. During the Early Cretaceous local large sauropods and theropods left a great abundance of footprints. Later in the Cretaceous, the state was covered by the Western Interior Seaway and home to creatures like mosasaurs, plesiosaurs, and few icthyosaurs. Early Cenozoic Texas still contained areas covered in seawater where invertebrates and sharks lived. On land the state would come to be home to creatures like glyptodonts, mammoths, mastodons, saber-toothed cats, giant ground sloths, titanotheres, uintatheres, and dire wolves. Archaeological evidence suggests that local Native Americans knew about local fossils. Formally trained scientists were already investigating the state's fossils by the late 1800s. In 1938, a major dinosaur footprint find occurred near Glen Rose. Pleurocoelus was the Texas state dinosaur from 1997 to 2009, when it was replaced by Paluxysaurus jonesi after the Texan fossils once referred to the former species were reclassified to a new genus.

References

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