The Mississippi River Alluvial Plain is an

alluvial plain An alluvial plain is a largely flat landform created by the deposition of sediment over a long period of time by one or more rivers coming from highland regions, from which alluvial soil forms. A floodplain is part of the process, being the smal ...

created by the

Mississippi River The Mississippi River is the List of longest rivers of the United States (by main stem), second-longest river and chief river of the second-largest Drainage system (geomorphology), drainage system in North America, second only to the Hudson B ...

on which lie parts of seven U.S. states, from southern Louisiana to southern Illinois (Illinois, Missouri, Kentucky, Tennessee, Arkansas, Mississippi, Louisiana). The plain is divided into (a) the

Mississippi River Delta The Mississippi River Delta is the confluence of the Mississippi River with the Gulf of Mexico in Louisiana, southeastern United States. The river delta is a area of land that stretches from Vermilion Bay on the west, to the Chandeleur Isl ...

in the southern half of

Louisiana Louisiana , group=pronunciation (French: ''La Louisiane'') is a state in the Deep South and South Central regions of the United States. It is the 20th-smallest by area and the 25th most populous of the 50 U.S. states. Louisiana is bord ...

and (b) the upper Mississippi Embayment running from central Louisiana to Illinois. The term "Mississippi embayment" is sometimes used more narrowly to refer to its section on the western side of the river, running through eastern

Arkansas Arkansas ( ) is a landlocked state in the South Central United States. It is bordered by Missouri to the north, Tennessee and Mississippi to the east, Louisiana to the south, and Texas and Oklahoma to the west. Its name is from the O ...

, southeastern

Missouri Missouri is a state in the Midwestern region of the United States. Ranking 21st in land area, it is bordered by eight states (tied for the most with Tennessee): Iowa to the north, Illinois, Kentucky and Tennessee to the east, Arkansas t ...

, westernmost

Tennessee Tennessee ( , ), officially the State of Tennessee, is a landlocked U.S. state, state in the Southeastern United States, Southeastern region of the United States. Tennessee is the List of U.S. states and territories by area, 36th-largest by ...

(east side of the River), westernmost

Kentucky Kentucky ( , ), officially the Commonwealth of Kentucky, is a state in the Southeastern region of the United States and one of the states of the Upper South. It borders Illinois, Indiana, and Ohio to the north; West Virginia and Virginia ...

(east side of the River) and southernmost

Illinois Illinois ( ) is a state in the Midwestern United States. Its largest metropolitan areas include the Chicago metropolitan area, and the Metro East section, of Greater St. Louis. Other smaller metropolitan areas include, Peoria and Rock ...

, and excluding northwest

Mississippi Mississippi () is a state in the Southeastern region of the United States, bordered to the north by Tennessee; to the east by Alabama; to the south by the Gulf of Mexico; to the southwest by Louisiana; and to the northwest by Arkansas. Miss ...

where the alluvial plain is known as the

Mississippi Delta The Mississippi Delta, also known as the Yazoo–Mississippi Delta, or simply the Delta, is the distinctive northwest section of the U.S. state of Mississippi (and portions of Arkansas and Louisiana) that lies between the Mississippi and Yaz ...

. It is the largest

ecoregion An ecoregion (ecological region) or ecozone (ecological zone) is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than a biogeographic realm. Ecoregions cover relatively large areas of ...

, covering , and including all of the historic Mississippi River

floodplain A floodplain or flood plain or bottomlands is an area of land adjacent to a river which stretches from the banks of its channel to the base of the enclosing valley walls, and which experiences flooding during periods of high discharge.Goudi ...

References

Mississippi River Mississippi embayment Floodplains of the United States Plains of the United States Physiographic sections {{Louisiana-geo-stub