The geology of Alabama is marked by abundant geologic resources and a variety of geologic structures from folded mountains in the north to sandy beaches along the

Gulf of Mexico The Gulf of Mexico ( es, Golfo de México) is an oceanic basin, ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of ...

coast. Alabama spans three continental

geologic province A geologic province is a spatial entity with common geologic attributes. A province may include a single dominant structural element such as a basin or a fold belt, or a number of contiguous related elements. Adjoining provinces may be simila ...

s as defined by the

United States Geological Survey The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, ...

, the Atlantic Plain, Appalachian Highlands, and Interior Plains.
USGS; Geologic Provinces of the United States: Records of an Active Earth The Geological Survey of Alabama breaks these provinces down into more specific physiographic provinces.
Geologic Survey of Alabama; Geologic Map; Northwest Section Legend

Provinces

East Gulf Coastal Plain

The broad, flat coastal plain stretches across the southern portion of the state, extending north from the Gulf coast to the Atlantic Seaboard fall line, Fall Line near

Montgomery, Alabama Montgomery is the capital city of the U.S. state of Alabama and the county seat of Montgomery County. Named for the Irish soldier Richard Montgomery, it stands beside the Alabama River, on the coastal Plain of the Gulf of Mexico. In the 202 ...

. A Tapestry of Time and Terrain: The Union of Two Maps – Geology and Topography; Physiographic Regions

Appalachian Highlands

Extending north from the Fall Line to far northern Alabama, the Appalachian Highlands encompass the hills, valleys, mountains, and plateaus that make up the southern extent of the

Appalachian Mountains The Appalachian Mountains, often called the Appalachians, (french: Appalaches), are a system of mountains in eastern to northeastern North America. The Appalachians first formed roughly 480 million years ago during the Ordovician Period. They ...

. This province is further subdivided into the Piedmont, Valley and Ridge, and Appalachian Plateaus provinces.

Interior Plains

Extreme north Alabama marks the southeast border of the Interior Plains province, characterized by flat or gently rolling terrain. In Alabama, this province generally lies north of the

Tennessee River The Tennessee River is the largest tributary of the Ohio River. It is approximately long and is located in the southeastern United States in the Tennessee Valley. The river was once popularly known as the Cherokee River, among other names, ...

. This province is further divided into the Interior Low Plateaus province.

Seismology

Alabama experiences frequent small earthquakes detectable only by instruments, and occasional moderate earthquakes large enough to be felt over a wide area and resulting in minor damage.
Faulk, Kent. Alabama isn't immune to earthquakes, scientists say; Birmingham News; April 20, 2008 The largest earthquake in recorded Alabama history measured an estimated magnitude of 5.1 and occurred October 18, 1916 Irondale earthquake, 1916 near Irondale, and resulted in widespread panic, damage to structures, and dramatic changes in water well levels. Since 1886, slightly more than 10 percent of earthquakes with an epicenter in Alabama have been an estimated magnitude 3 or greater. The April 29, 2003 earthquake centered near

Fort Payne, Alabama Fort Payne is a city in and county seat of DeKalb County, in northeastern Alabama, United States. At the 2020 census, the population was 14,877. European-American settlers gradually developed the settlement around the former fort. It grew rapid ...

was felt over a wide area and received extensive media coverage. Two fault zones are found in Alabama, the Southern Appalachian Seismic Zone (also known as the

Eastern Tennessee Seismic Zone The Eastern Tennessee Seismic Zone (ETSZ), also known as the East Tennessee Seismic Zone and the Southern Appalachian Seismic Zone, is a geographic band stretching from northeastern Alabama to southwestern Virginia that is subject to frequent small ...

) in northeast and central Alabama, and the Bahamas Fracture Seismic Zone in southwest Alabama. Alabama also lies within the influence of the

New Madrid Seismic Zone The New Madrid Seismic Zone (), sometimes called the New Madrid Fault Line, is a major seismic zone and a prolific source of intraplate earthquakes (earthquakes within a tectonic plate) in the Southern and Midwestern United States, stretching t ...

and the South Carolina Seismic Zone, earthquakes in those zones have resulted in damage in Alabama. The northeast corner of the state is subject to the greatest peak accelerations due to the presence of the East Tennessee Seismic Zone.

Natural resources

Alabama's abundant natural mineral resources include commercially viable deposits of coal, oil, natural gas, and various minerals such as limestone and marble. The

Cahaba Basin The Cahaba Basin is a geologic area of central Alabama developed for coal and coalbed methane (CBM) production. Centered in eastern Bibb and southwestern Shelby Counties, the basin is significantly smaller in area and production than the larger ...

and

Black Warrior Basin The Black Warrior Basin is a geologic sedimentary basin of western Alabama and northern Mississippi in the United States. It is named for the Black Warrior River and is developed for coal and coalbed methane production, as well as for convention ...

in central Alabama produce coalbed methane. Extensive oil and gas deposits have been developed in the southern portion of the state,

Mobile Bay Mobile Bay ( ) is a shallow inlet of the Gulf of Mexico, lying within the state of Alabama in the United States. Its mouth is formed by the Fort Morgan Peninsula on the eastern side and Dauphin Island, a barrier island on the western side. The ...

, and coastal state waters. The first scientific reports of Alabama's geology were made during field studies by R. T. Brumby in the late 1830s and Sir

Charles Lyell Sir Charles Lyell, 1st Baronet, (14 November 1797 – 22 February 1875) was a Scottish geologist who demonstrated the power of known natural causes in explaining the earth's history. He is best known as the author of ''Principles of Geolo ...

in the early 1840s.

Michael Tuomey Michael Tuomey (September 29, 1805 – March 30, 1857) was the State Geologist of South Carolina from 1844 to 1847, and the first State Geologist of Alabama, appointed in 1848 and serving until his death. His early descriptions and maps of the Bi ...

, appointed state geologist in 1847, completed a ''Geological Map of Alabama'' and in 1849 and published the first of two comprehensive reports on the state's resources a year later. These publications did much to quantify the mineral wealth of the

Birmingham District The Birmingham District is a geological area in the vicinity of Birmingham, Alabama, where the raw materials for making steel, limestone, iron ore, and coal are found together in abundance. The district includes Red Mountain, Jones Valley, and ...

and helped establish the region's early iron industry. Tuomey was succeeded by

Eugene Allen Smith Eugene Allen Smith (October 27, 1841 – September 7, 1927) was an American geologist. He was born in the (now former) town of Washington, Alabama, in 1841, the son of Samuel Parrish Smith and his wife Adelaide Julia Allen. After an education in ...

, who built on the initial researches to establish the geological history of the state.

Meteor crater

A meteor crater over five miles in diameter was identified near

Wetumpka, Alabama Wetumpka () is a city in and the county seat of Elmore County, Alabama, Elmore County, Alabama, United States. At the 2020 United States Census, 2020 census, the population was 7,220. In the early 21st century Elmore County became one of the f ...

in 1969–1970. Conclusive evidence of the origin of the Wetumpka Impact Crater was found by

Auburn University Auburn University (AU or Auburn) is a public land-grant research university in Auburn, Alabama. With more than 24,600 undergraduate students and a total enrollment of more than 30,000 with 1,330 faculty members, Auburn is the second largest uni ...

geology professor David T. King in 1998.
Earth Impact Database. Retrieved on April 24, 2008

References

External links

Survey of Alabama
– State of Alabama
Department of Geological Sciences
– University of Alabama {{DEFAULTSORT:Geology Of Alabama Natural history of Alabama

Alabama (We dare defend our rights) , anthem = "Alabama (state song), Alabama" , image_map = Alabama in United States.svg , seat = Montgomery, Alabama, Montgomery , LargestCity = Huntsville, Alabama, Huntsville , LargestCounty = Baldwin County, Al ...