Geography of Texas

The geography of Texas covers a wide and far reaching scope. Occupying about 7% of the total water and land area of the, it is the second largest state after , and is the southernmost part of the , which ends in the south against the folded  of. is in the south-central part of the United States of America, and is considered to form part of the and also part of the.

The, and  all provide natural state lines where Texas borders  on the north,  and  on the east, and  and the  states of , , , and  to the south. , the state capital, is farther south than all other US state capitals except.

By residents, the state is generally divided into, , , , and , 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 and, although the fact that Texas was granted (and retains to this day)  may be a historical motive for Texans defining their state as containing exactly five regions.

Some regions of Texas are associated with the South more than the Southwest (primarily and ), while other regions share more similarities with the Southwest than the South (primarily  and ). Even the northwestern part of the state seems to have more in common with parts of the United States (Kansas and Nebraska) that are considered "" and never "southern". The size of Texas prohibits easy categorization of the entire state wholly in any recognized region of the United States; geographic, economic, and even cultural diversity between regions of the state preclude treating Texas as a region in its own right.

Climate
,, and are the three major  of Texas, with no distinguishable boundaries. Modified Marine, or subtropical, dominates the majority of the state. Texas has an annual range from 60.57  (1,538.5 ) in, East Texas, to 9.43 inches (239.5 ) in. The record high of 120 ° (49 °) was reached at on Aug. 12, 1936, and  on June 28, 1994. The low also ties at -23 ° (-31 °) in on Feb. 12, 1899, and  on Feb. 8, 1933.

Physical geography
With 10 climatic regions, 14 soil regions, and 11 distinct ecological regions, classifing regions becomes problematic with differences in soils, topography, geology, rainfall, and plant and animal communities. The geographic center of Texas is about 15 miles (24 ) northeast of in northern. , at 8,749 (2,667 ) above  is the highest point in Texas. The lowest being sea level where Texas meets the Gulf of Mexico. Texas has five state forests and 120 s for a total over 605,000 (2,450 ). There are 3,700 named streams and 15 major river systems flowing through 191,000 miles (307,385 ) of Texas. Eventually emptying into seven major, these rivers support over 212.

Texas is so large in its east-west expanse that, in the western corner of the state, is closer to than to , near the Louisiana state line; Beaumont, in turn, is closer to  than it is to El Paso. Also,, in the northeastern corner of the state, is about the same distance from as it is to El Paso. The north-south expanse is similarly impressive;, in the northwestern corner of the state, is closer to the state capitals of , , , and  than it is to , its own state capital.

Gulf Coastal Plains
The from the  inland to the Balcones Fault and the. This large area stretches from the cities of to  to  but shows a large variety in vegetation. The thick pineywoods of east Texas and the brush country south of San Antonio are found here. With about 20 to over 58 es (508-1,480 ) annual rainfall, this is a nearly level, drained plain dissected by streams and rivers flowing into estuaries and es. Windblown sands and dunes, grasslands, oak mottes and salt marshes make up the seaward areas. s include, and the.

Interior Lowlands
The Interior Lowlands are bounded by the to the west, the  to the south, and the  to the east. This area includes the North Central Plains around the cities of and, the  to the west of , the , and the Eastern Cross Timbers to the east of. With about 35 to 50 es (889-1,270 ) annual rainfall, gently rolling to hilly forested land is part of a larger pine-hardwood forest of s,, and  trees. Soils vary from coarse sands to tight clays or red-bed clays and shales. The only National Park in this region is.

Great Plains
The include the, the , , , and the. It is bordered on the east by the in the panhandle and by the  to the southeast. Cities in this region include, , and , , and. The is a popular name for the area of hills along the  and is a transitional area between the  and the. With about 15 to 31 es (381-787 millimeter|mm) annual rainfall, the southern end of the Great Plains are gently rolling plains of shrub and grassland, and home to the dramatic and  state parks. The largest concentration of s in the world (nearly 22,000) is on the Southern High Plains of Texas and Eastern.

Texas's were some of the first areas farmed in Texas. Highly expansive s with characteristic dark coloration, called the Houston Black series, occur on about 1.5 million (6,000 ) extending from north of Dallas south to San Antonio. The Professional Soil Scientists Association of Texas has recommended to the State Legislature that the Black series be designated the State soil. The series was established in 1902. National Parks in this area are the and the.

Basin and Range Province
Trans-Pecos Natural Region with less than 12 es (305 millimeter|mm) annual rainfall. The most complex Natural Region, it includes Sand Hills, the Stockton Plateau, desert valleys, wooded mountain slopes and desert grasslands. The in extreme western Texas, west of the  beginning with the  on the east and the  to its west and south. The region is the only part of Texas regarded as mountainous and includes seven named peaks in elevation greater than 8,000  (2,400 ). With less than 12 es (305 millimeter|mm) annual rainfall, this region includes sand hills, desert valleys, wooded mountain slopes and desert grasslands. The vegetation diversity includes at least 268 species and 447 species of s.  National Parks include the, , , , , and the.

Geology
Texas is mostly, with east Texas underlain by a and younger sequence of sediments, the trace of ancient shorelines east and south until the  of the  is met. This sequence is built atop the subsided crest of the ––Marathon Mountains zone of, which collapsed when  in  time opened the Gulf of Mexico. West from this crest, which is buried beneath the ––– trend, the sediments are  and  in age. 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. A few exposures of  and  rocks are found in the central and western parts of the state, and   rocks are found in far west Texas, in the  area. A blanket of sediments known as the Ogallala formation in the western high plains region is an important. Texas has no active or dormant volcanoes and few earthquakes, being situated far from an active boundary. (The 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 enormous s, Texas is a major and  state. It leads all other states in such categories as oil, cattle, sheep, and cotton. Texas also produces poultry, eggs, dairy products, greenhouse and nursery products, wheat, hay, rice, sugar cane, and peanuts, and a range of fruits and vegetables.
 * -bearing rocks, mainly cretaceous limestones, occur in, , , , and other counties.
 * Deposits of are widely distributed in Texas, but most are minor.
 * is currently produced in Bexar, Comal, Dallas, Ector, Ellis, El Paso, Harris, Hays, McLennan, Nolan, Nueces, Potter, and Tarrant counties. Historically, Texas' Portland cement output accounts for about 10% of the annual United States production.
 * With an abundance of various types of s, Texas is one of the leading producers of clays.
 * occurs primarily in Coleman, Eastland, Erath, Jack, McCulloch, Montague, Palo Pinto, Parker, Throckmorton, Wise, and Young counties of Texas., or brown coal, occurs in deposits in the Texas Coastal Plain.
 * deposits in Texas occur in the Trans-Pecos region, in north central Texas, and in the Llano region. Most of the state's small production has been from the Van Horn-Allamoore mining district, whereas only small shipments of copper have been reported from the North Texas and Llano regions.
 * Fluorspar or is an important industrial mineral used in the manufacture of, aluminum, , and fluorocarbons. It occurs at several localities in the Trans-Pecos and Llano regions of Texas.
 * Collecting rock and mineral specimens has proved quite profitable., , , , , , , , and  are all commonly collected.
 * Deposits of occur in the Llano region and was previously produced in Burnet County.
 * Bat occurs in numerous caverns in the Edwards Plateau and in the Trans-Pecos region and to a more limited extent in Central Texas.
 * is extensively developed in Texas where the main occurrences are in the Permian Basin, the Cretaceous Edwards Formation in Gillespie and Menard counties, and the Gulf Coast salt domes of Harris County and previously Brooks County.
 * Texas is the leading producer of solely from the Cliffside gas field near Amarillo.
 * Deposits of are present in northeastern Texas as well as several in Central Texas.
 * s, abundant in many parts of Texas, are utilized in the manufacture of lime. Plants for the production of lime are currently operating in Bexar, Bosque, Burnet, Comal, Deaf Smith, Hill, Johnson, Nueces, and Travis counties.
 * , and other mineral salts are present in the Upper Permian basin and in the underlying playas of the High Plains.
 * is known to occur in Precambrian rocks in Mason and Llano counties, in Val Verde County, in Jeff Davis County, and in Dickens County.
 * mineral deposits occur in southern Brewster and southeastern Presidio counties, where mining was initiated in 1896. With all of the mines closed in the early 1970s, no production has been reported since 1973.
 * is present in Precambrian pegmatite in the Llano region.
 * Common occurs on the Texas Coastal Plain.
 * and shells occur bordering the Gulf of Mexico and in some sediments along the Texas Coastal Plain.  Shells were extensively produced until the early 1960s, when production was discontinued because of environmental issues.
 * Elements of the series are commonly termed rare-earth elements. Several of the rare earths have anomalous concentrations in the rhyolitic and related igneous rocks in the Trans-Pecos area of Texas. A deposit containing several rare-earth minerals was exposed at Barringer Hill in Llano County before it was covered by the waters of Lake Buchanan.
 * s occurs in large quantities in salt domes in the Texas Coastal Plain and with other evaporites in the Permian Basin of West Texas, as well as near.
 * s used for industrial purposes commonly have been found in the Texas Coastal Plains, East Texas, north central Texas, and Central Texas.
 * The discovery of in Texas has been credited by some to Franciscans who discovered and operated mines near El Paso about 1680.  Documented silver production started in the late 1880s at the Presidio Mine, in Presidio County.  Texas produced 32,663,405 troy ounces of silver between 1885 and 1955
 * Materials suitable for or building stone, can be found in most parts of the state except the High Plains and the Gulf Coastal Plains. Granite, limestone, and sandstone are currently the only stones being produced.
 * occurs in the caprocks of salt domes in the Gulf Coastal Plain, in Permian-age bedded deposits in Trans-Pecos Texas.
 * In the past was produced from surface mines in Atascosa, Gonzales, Karnes, and Live Oak counties. All uranium mines are closed and Texas is no longer a producer.